Starting pathology (from Female reproductive system)

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Latter half of Starting pathology:

Contents

Female reproductive system:

Cervical biopsy

Author: Mikael Häggström [note 1]
This article includes endocervical curettage (ECC).

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation


Gross processing

Example report:

(Optionally: A. Container is labeled - __. The specimen is received in formalin and consists of ) 1 fragment(s) of pink-tan tissue with a vaguely recognizable mucosal surface. The tissue measures __ cm. (The surgical margin is inked black. The specimen is bisected and entirely submitted for microscopic examination in one cassette.)

Microscopic evaluation

Anatomic/Histologic location

Describe mucosa as squamous (or ectocervical), endocervical (generally mucinous and glandular) or transformation zone mucosa.

Pathologies

edit
Look for cervical dysplasia. It is mainly seen as nuclei with hyperchromasia, coarse chromatin and irregular contours.[3]

Further information: Cervical dysplasia

edit
Other common findings:

Example report

Endocervix, curettings:
Fragments of squamous and endocervical glandular epithelium without significant histopathologic changes.
Negative for dysplasia.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Gulisa Turashvili, M.D., Ph.D.. Cervix Benign / nonneoplastic epithelial lesions. Nabothian cysts.. Pathology Outlines. Last author update: 1 February 2021. Last staff update: 4 April 2022}}
  2. International Federation for Cervical Pathology and Colposcopy (IFCPC) classification. References:
    -. Transformation zone (TZ) and cervical excision types. Royal College of Pathologists of Australasia.
    - Jordan, J.; Arbyn, M.; Martin-Hirsch, P.; Schenck, U.; Baldauf, J-J.; Da Silva, D.; Anttila, A.; Nieminen, P.; et al. (2008). "European guidelines for quality assurance in cervical cancer screening: recommendations for clinical management of abnormal cervical cytology, part 1 ". Cytopathology 19 (6): 342–354. doi:10.1111/j.1365-2303.2008.00623.x. ISSN 0956-5507. PMID 19040546. 
  3. Khaled J. Alkhateeb, M.B.B.S., Ziyan T. Salih, M.D.. HSIL / CIN II / CIN III. PathologyOutlines. Topic Completed: 29 March 2021. Minor changes: 9 February 2022
  4. Source image by Ed Uthman from Houston, TX, USA. Creative Commons Attribution 2.0 Generic (CC BY 2.0) license
  5. Anissa Ben Amor.. Cervical Ectropion. StatPearls, National Center for Biotechnology Information. Last Update: November 14, 2021.
    - This book is distributed under the terms of the Creative Commons Attribution 4.0 International License

Image sources


Cervical cone

Unless otherwise specified, the primary focus is any cervical neoplasia.

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Gross processing

  • Measure length, as well as the transverse and sagittal diameter of the ectocervical surface.[1]
  • Optionally, weight the sample.[1]
  • Note the symmetry of the sample, and the position of the cervical canal.[1]
  • Note whether the circumference is complete. If not, and the directions are indicated on the cone, determine the approximate position of the defect.[1]
  • Cones excised by knife should be inked on the excision surfaces. Those excised by laser do not need inking.[1]

Selection and trimming

Gross preparation of cervical cone.svg
  • If the cone is more than 1 cm long, take transverse slices from the top of the cone and towards the ectocervix, and stop when approximately 1 cm of the ectocervical portion of the cone remains.
  • Cut the portion into radial or sagittal slices. Sagittal slices are made perpendicularly to the portion surface, and should be divided into at least the four quadrants.[note 1][1]

In cases where the cone is small and fragmented, try to orient the preparations and divide them if possible to obtain sagittal slices.[1]

  See also: General notes on gross processing

 

Microscopic evaluation

Anatomic/Histologic location

Describe mucosa as squamous (or ectocervical), endocervical (generally mucinous and glandular) and/or transformation zone mucosa.

Cervical dysplasia

edit
Look for cervical dysplasia. It is mainly seen as nuclei with hyperchromasia, coarse chromatin and irregular contours.[3]

Further information: Cervical dysplasia


Radicality

Locations of non-radicality should be reported in relation to tissue markings (such as needles), or in terms of quadrants or corresponding to a clock face, based on the patient being in supine position.

Look whether there is normal epithelium on each side of all slices where neoplasia is seen, and when the epithelium is missing in any direction, consider ordering additional serial sections or step sections.

HPV changes

Also look koilocytic changes of human papillomavirus (HPV), with such cells typically displaying:

  • Nuclear enlargement (two to three times normal size).
  • Irregularity of the nuclear membrane contour, creating a wrinkled or raisinoid appearance.
  • A darker than normal staining pattern in the nucleus, known as hyperchromasia.
  • Perinuclear cytoplasmic vacuolization ("nuclear halo").

Other findings

edit
Other common findings:

Microscopy report

If a neoplasia is found, the report should include:[1]

  • The histolopathological type and degree of differentiation
  • Location and extent
  • Radicality
Histopathology of CIN 3.jpg

High-grade squamous intraepithelial lesion (CIN-2), present at 3:00 to 12:00.
All margins of excision are negative for CIN-2.

Example report in a normal case:

Cervix at transformation zone without significant histopathologic changes.
Negative for neoplasia/carcinoma.


Endometrial polyp

Author: Mikael Häggström [note 2]

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Microscopic evaluation

The main objectives are:

  • Making a diagnosis of endometrioid polyp. An endometrial polyp may be diagnosed in the presence of 2 of the following 3:
  • Thick-walled vessels
  • Collagenous stroma
  • Epithelium on at least 3 sides
  • Look for signs of atypia or malignancy.

Reporting

Most importantly:

  • Benign versus malignant (or presence or absence of atypia.)
  • ((The size of the polyp.))
  • ((The type of epithelium at both the surface and gland coverings.))

Example of a minimal report:

Benign endometrial polyp.
  See also: General notes on reporting

Notes

  1. Each slice may be individually numbered.
  2. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Monica Dahlgren, Janne Malina, Anna Måsbäck, Otto Ljungberg. Stora utskärningen. KVAST (Swedish Society of Pathology). Retrieved on 2019-09-26.
  2. International Federation for Cervical Pathology and Colposcopy (IFCPC) classification. References:
    -. Transformation zone (TZ) and cervical excision types. Royal College of Pathologists of Australasia.
    - Jordan, J.; Arbyn, M.; Martin-Hirsch, P.; Schenck, U.; Baldauf, J-J.; Da Silva, D.; Anttila, A.; Nieminen, P.; et al. (2008). "European guidelines for quality assurance in cervical cancer screening: recommendations for clinical management of abnormal cervical cytology, part 1 ". Cytopathology 19 (6): 342–354. doi:10.1111/j.1365-2303.2008.00623.x. ISSN 0956-5507. PMID 19040546. 
  3. Khaled J. Alkhateeb, M.B.B.S., Ziyan T. Salih, M.D.. HSIL / CIN II / CIN III. PathologyOutlines. Topic Completed: 29 March 2021. Minor changes: 9 February 2022
  4. Source image by Ed Uthman from Houston, TX, USA. Creative Commons Attribution 2.0 Generic (CC BY 2.0) license
  5. Anissa Ben Amor.. Cervical Ectropion. StatPearls, National Center for Biotechnology Information. Last Update: November 14, 2021.
    - This book is distributed under the terms of the Creative Commons Attribution 4.0 International License
  6. Owings, Richard A.; Quick, Charles M. (2014). "Endometrial Intraepithelial Neoplasia ". Archives of Pathology & Laboratory Medicine 138 (4): 484–491. doi:10.5858/arpa.2012-0709-RA. ISSN 1543-2165. 
  7. Stewart, Colin J.R.; Crum, Christopher P.; McCluggage, W. Glenn; Park, Kay J.; Rutgers, Joanne K.; Oliva, Esther; Malpica, Anais; Parkash, Vinita; et al. (2019). "Guidelines to Aid in the Distinction of Endometrial and Endocervical Carcinomas, and the Distinction of Independent Primary Carcinomas of the Endometrium and Adnexa From Metastatic Spread Between These and Other Sites ". International Journal of Gynecological Pathology 38: S75–S92. doi:10.1097/PGP.0000000000000553. ISSN 0277-1691. 
    - "Figures - available via license: Creative Commons Attribution 4.0 International"
  8. Rabban, Joseph T.; Gilks, C. Blake; Malpica, Anais; Matias-Guiu, Xavier; Mittal, Khush; Mutter, George L.; Oliva, Esther; Parkash, Vinita; et al. (2019). "Issues in the Differential Diagnosis of Uterine Low-grade Endometrioid Carcinoma, Including Mixed Endometrial Carcinomas ". International Journal of Gynecological Pathology 38: S25–S39. doi:10.1097/PGP.0000000000000512. ISSN 0277-1691. 
  9. Mohamed Mokhtar Desouki. Uterus - Stromal tumors - Leiomyoma. pathology Outlines. Topic Completed: 1 August 2011. Revised: 15 December 2019

Image sources

Endometrial curettings

Gross processing

  • Generally submit all tissue for microscopy, even larger volumes.
  • Look for products of conception if indicated from referral and/or history

Microscopic evaluation

Describe the anatomic/histologic type of epithelium.

Look mainly for:

Anatomic/histologic epithelium type

(Determine the type or phase of the endometrium:) edit

In contrast, endocervical mucosa typically consists of mucinous columnar epithelium and mucinous glands. Evaluate this like a cervical biopsy or cervical cone.

The phases of endometrium through the menstrual cycle:

If you want to specify the phase by day, then it's more accurate to state it as days past ovulation where applicable, since the follicular phase may vary substantially.

Hyperplasia, atypa and/or malignancy

  • Look for signs of atypia or malignancy:

edit

Microscopy report

Example in a normal case:

(Endometrial curettings:
Benign proliferative endometrium and endocervical mucosa without significant histopathologic changes.)
Negative for neoplasia ((or viral cytopathic changes)).


Endometrial thickening

Hysterectomy sampling

A regular hysterectomy grossing is performed, but with the following sampling:[5]

  • 2 longitudinal sections through ecto/endocervix (1 anterior and 1 posterior)
  • 2 longitudinal sections through upper endocervix/lower uterine segment (1 anterior and 1 posterior), immediately adjacent to the sections taken from the cervix
  • 4 full-thickness representative sections of endomyometrium (2 anterior and 2 posterior)
  • Transversely section the remaining anterior and posterior endomyometrium (~1 cm thick). Submit the entire endometrium from the lower uterine segment to the fundus, maintaining orientation.
  • Submit entire fimbriae (longitudinally sectioned) and 2 representative cross-sections on each side.

Microscopic evaluation

  • Look for signs of atypia or malignancy:

edit

Reporting

Most importantly:

  • Presence or absence of atypia.


Hysterectomy

For a freshly received uterus, generally gross it fresh to include either opening it up (small specimen, no suspected malignancy seen) and/or serial sectioning, in order to let the formalin penetrate it properly. Ensure the endometrium is immersed in the formalin (such as having the serosa oriented upwards).

  See also: General notes on fixation

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))
Other legend

<< Decision needed between alternatives separated by / signs >>
{{Common findings / In case of findings}}
[[Comments]]
Link to another page

Gross processing

Gross examination

For orientation:

  • The round ligament lies anterior to the tubes and ovaries.[8]
  • The peritoneum extends further down along the cervix posteriorly than anteriorly.[9] Its ends bluntly posteriorly and sharply anteriorly.[9]

When received the same day as the surgery, perform the following steps at least to serial sectioning before putting (back) in formalin, preferably with paper towels between slices, so that it fixes properly:[8]

  • (Remove the adnexa.[8] Weigh the uterus without the adnexa.)
  • Perform a general inspection
  • Measure the 3 dimensions, including the cervix. (Also measure the length of the cervix, the maximum diameter of the cervix, and the width of the cervical os.)
  • (Ink the surgical margin of the cervix for orientation, such as black on the posterior side.)
  • Open the uterus by transmural radial cuts on both sides of the uterine cavity.[note 1] The cavity is sometimes be squeezed or rolled around a leiomyoma, and you'll you have to improvise and perhaps go around the leiomyoma to open the cavity properly.
  • Inspect the mucosa. If any polyps: Further information: Endometrial polyp
    If more extensive tumor, gross as per endometrial cancer
  • Serially section through almost the entire depth of the myometrium at approximately 1 cm intervals, still keeping the specimen together.
  • Measure the thickness of the mucosa and myometrium
  • Inspect the myometrium. If any tumor: Further information: Smooth muscle tumor

Gross report

Applicable in bleeding disorders, pain, leiomyoma and endometrial hyperplasia:[8]

Components:[8]

  • (Shape of uterus and adnex)
  • Measurements
  • Mucosa, such as smooth or irregular.
  • (Even the absence of) any polyps. Further information: Endometrial polyp
  • Mucosal and endometrial thickness. Further information: Endometrial thickening
  • (Even the absence of) any smooth muscle tumor. Further information: Smooth muscle tumor
Example
(A. Labeled - __. The specimen is received in formalin and consists of a resected) uterus with cervix [and bilateral fallopian tubes and ovaries]. The uterus and cervix measure __ ((cm superior to inferior)) x __ ((cm cornu to cornu)) x __ cm ((anterior to posterior,)) and weighs ___ grams. The serosa is [tan-pink and smooth]. The cervix measures ___ cm in diameter and ___ cm in length. The ectocervical mucosa is [tan-pink and smooth] and the cervical os[ is patent] and measures ___ cm in diameter. The specimen is bisected in the coronal plane. The endocervical canal is [patent and displays a tan-pink smooth mucosa]. The endometrial cavity is [triangular] and is lined by[ smooth] endometrium measuring [0.1] cm in average thickness. The myometrium measures up to ___ cm in thickness.[

- It displays __ intramural leiomyomata measuring up to __ cm in greatest diameter.

] The right ovary measures ___ cm and has a [tan-pink and smooth] capsule. Cut sections show [no gross lesions]. The right fallopian tube measures ___ cm in length and ___ cm in average diameter. The serosa [is tan-pink and smooth]. Cut sections reveal a small patent lumen and no gross lesions. The left ovary measures ___ cm and has a [tan-pink and smooth] capsule. Cut sections show [no gross lesions].The left fallopian tube measures ___ cm in length and ___ cm in average diameter. The serosa [is tan-pink and smooth]. Cut sections reveal a small patent lumen and no gross lesions. Representative sections are submitted for microscopic examination in ___ cassettes.

Slices for microscopy

Applicable in bleeding disorders, pain, leiomyoma and endometrial hyperplasia:[8]

Submit:[8][10]

  • One, (two - at 6 and 12 o'clock), ((or four)) cross-sections from any accompanying ectocervix/endocervix (aiming to include the transformation zone). In subtotal extirpation, a cross-section is taken from the lower resection border.
  • ((A transverse slice through the endocervix, possibly divided into two.))
  • Endometrium and myometrium, by one slice from the front and one from the back wall of the corpus.
  • {{Any mucosal parts with macroscopically abnormal appearance, including polyps.}}
  • {{For any area suspicious for malignancy, submit a full cross-section of the uterine wall that includes the serosa. Use multiple contiguous cassettes if needed.}}
  • {{Samples from all smooth muscle tumors >5 cm in diameter.}} Further information: Smooth muscle tumor

A specific sampling scheme is used in: Endometrial thickening

See also:

Microscopic evaluation

Look for signs of malignancy:

Cervix

edit
Look for cervical dysplasia. It is mainly seen as nuclei with hyperchromasia, coarse chromatin and irregular contours.[11]

Further information: Cervical dysplasia

edit
Other common findings:

Uterine body

(Determine the type or phase of the endometrium:) edit

In contrast, endocervical mucosa typically consists of mucinous columnar epithelium and mucinous glands. Evaluate this like a cervical biopsy or cervical cone.

The phases of endometrium through the menstrual cycle:

If you want to specify the phase by day, then it's more accurate to state it as days past ovulation where applicable, since the follicular phase may vary substantially.

Main pathologic findings

edit

Microscopy report

Examples of reports:

Normal cases
[note 2]
Uterus, cervix, bilateral tubes and ovaries, abdominal hysterectomy and bilateral salpingo-oophorectomy:
  • Benign cervix.
  • Benign inactive endometrium.
  • {{Leiomyomata and adenomyosis.}}
  • Benign ovaries.
  • Benign fallopian tubes.
  • Negative for malignancy.
Microscopy of hysterectomy shows ecto and endocervix without atypia. The glands have columnar epithelium without atypia.

In the uterine cavity, there is endometrial mucosa with ordinary thickness and regularly arranged endometrial glands. (Optionally: Description of likely menstrual phase.) Sharp delimitation between endometrium and myometrium. The myometrium contains no focal changes. No evidence of malignancy.

Endometrial intraepithelial neoplasia
Uterus, cervix, bilateral tubes and ovaries, hysterectomy and bilateral salpingo-oophorectomy:
  • Endometrial intraepithelial neoplasia; entire endometrial/myometrial junction submitted for microscopic exam.
  • Benign lower uterine segment.
  • Benign bilateral tubes and ovaries.


Smooth muscle tumor

Smooth muscle tumor (in this case leiomyoma).

Gross processing

Gross examination

Fibroid locations.

When finding fibroids (spherical tumors with whorled pattern, which in the uterus can be presumed to be smooth muscle tumors), examine and describe:[8]

  • Location. If in the uterus:
  • Intramural/submucosal/subserosal (see image)
  • (Posterior/anterior/right or left lateral.)
  • Number of tumors, if multiple. May be described simply as "multiple".
  • Size (may be described as "up to ___ cm in greatest dimension".
  • (Presence or absence of any hemorrhage or necrosis.)
  • ((Demarcation))

Selection

In case of hysterectomy, submit pieces from all fibroids >5 cm in diameter.[8]

Submit any macroscopically abnormal parts of the fibroids (hemorrhagic, necrotic, brittle or softening areas, and areas with blurry delimitation).[8]

For fibroids that are significantly calcified, a gross-only description as a calcified fibroid is generally sufficient, without the need to decalcify it to dissect it or sample from it.[note 3]

Microscopic examination

Distinguish leiomyoma (benign) from leiomyosarcoma (malignant) by looking at the latter's criteria:[16]

  • Marked cellular atypia
  • Mitoses: > 10 mitoses/10 high power fields
  • Necrosis

Diagnosis of conventional leiomyosarcoma requires 2 of these 3 histologic features.[16]

Further information: Evaluation of tumors

Microscopic report

Report:

  • Microscopic findings, including any visible linings
  • Diagnosis or most probable one
  • Any linings or borders.

Example, for a cervical polyp:

Polyp lined by a single layer of columnar epithelium consistent with endometrium. The interior consists of smooth muscles in a whorled pattern. No atypia. The finding is consistent with a pedunculated submucosal leiomyoma.

Intrauterine device

Gross processing

These are generally just visually described, with no samples for microscopic examination. Example report:

Copper IUD.jpg
T-shaped item with metal-coated arms and stem (Optionally: consistent with an intrauterine device with copper), with attached threads measuring 6.5 cm each.

Products of conception

Gross processing

Look up the gestational age of the pregnancy.

  • Look for fetal tissue (fetus, fetal membranes or chorionic villi). They are generally easier to distinguish from decidua (which is maternal tissue) when fragments are put in clear fluid and shaken, with chorionic villi having a consistency like orange pulp, whereas decidua is more rubbery. The fluid may be formalin if no sample for genetic workup is needed. If chorionic villi are found, no lengthy search is needed for other kinds of fetal tissue, just a quick look for obvious ones. Membranous material is less reliable, and may still indicate further sampling. Inspect any found fetal tissue for gross anomalies. If found, submit one piece of the fetus and one piece of the placenta.[19]
  • If fetal parts are not visually found, search for diagnostic placental tissue, which is soft and shaggy or spongy (as opposed to membranous, which is likely to be decidua or blood clots).[19]
  • If no fetal or placental tissue is found, all presented tissue generally needs to be submitted.

(If transported or processed together with other cases, put any chorionic villi in thin-mesh cassettes or tissue bags to limit contamination).[note 4]

Gross report

(Labeled - products of conception.) The specimen (is received <<fresh / in formalin>>) and consists of multiple fragments of soft tan-pink decidua, blood clots and amniotic sac measuring about 5 cc in aggregate. The intact amniotic sac measures 2.3 cm in greatest dimension. Fetal tissue is identified within the amniotic sac, measuring 1.0 cm in crown-rump length. Representative sections are submitted for microscopic examination (in 1 cassette).

Microscopy

The most important is to detect the presence of chorionic villi.

In the absence of chorionic villi, look for implantation site intermediate trophoblasts (ISITs):

  • In the absence of both chorionic villi and ISITs, preferably perform cytokeratin immunostaining of each tissue sample, such as CAM5.2.[20]
  • In the absence of chorionic villi and ISITs even after staining, call the clinician, since there may be an ectopic pregnancy.

Microscopy report

Examples:

Histopathology of chorionic villi at gestational age of 9 weeks.jpg

((Products of conception:)) Products of conception, including immature chorionic villi, corresponding to first trimester pregnancy. ((Spontaneous abortion, clinically.))

Histology of implantation site intermediate trophoblasts.jpg

((Products of conception:)) Fragments of focally necrotic decidua and implantation site, consistent with intrauterine products of conception. Negative for chorionic villi.


Fallopian tube

Gross processing

Paratubal cysts can be ignored if incidentally found.

(Look in the history for any intra-fallopian coils (Essure devices).)[note 5]

For sterilization
  • Measure length and average diameter of each tube
  • Serially section at 3-4 mm intervals,[21] or 2-3 mm if suspected malignant (including BRCA mutation).[22] Submit
  • Submit 1 (or 3) circumferential transverse sections. If the specimen is only a segment of the tube of less than <5mm((, ink the surgical cut surfaces and)) submit all tissue.[21]

Example gross report:

(A. Labeled - __. The specimen is received in formalin and consists of) two fimbriated segments of fallopian tube measuring __ cm in length and __ cm in average diameter. On sectioning, each displays a patent lumen. No gross abnormalities are identified. The tubes are unoriented. The specimen is serially cross-sectioned and representative sections are submitted for microscopic examination in two cassettes.

Microscopic examination

Fallopian tubes may be substantially edematous and congested, which can generally be attributed to surgery, in which case it does not need mention in the report.
  • Ensure there is at least one full cross-section from each tube, and take further samples otherwise.
  • Check for patency of the lumen.

Tumor

The most common tumor of the fallopian tubes is adenomatoid tumor:[23]

Reporting

Example of a normal report in sterilization:

(Right and left fallopian tubes, ((laparoscopic)) bilateral salpingectomy:)
Complete cross-sections of histologically unremarkable fallopian tubes.

When included in a uterus specimen, normal tubes and ovaries may simply be mentioned as:

Bilateral fallopian tubes and ovaries, unremarkable.
Histopathology of an ectopic pregnancy in a fallopian tube, with chorionic villi and implantation site changes Further information: Products of conception .

When done for ectopic pregnancy, report any rupture, either from the gross report or from microscopy, for example:

Benign ruptured fallopian tube with ectopic products of conception, including degenerated immature chorionic villi and implantation site with fresh hemorrhage.

Further information: Products of conception

Notes

    • In the US, the cut goes from side to side, through the cervix and uterine cavity, keeping the anterior and posterior halves attached by a relatively thin connection left at the fundus. It is done by cutting with scissors with the blunt end in the cervix and then uterine cavity, or by a blade guided on each side by the shanks of a pair of forceps inserted through the cervix.
    • In Sweden, the uterus is usually opened at the front in the midline, optionally with an incision towards each corner.
    It can be done by scissors, or by inserting a probe or forceps to guide a long blade.
  1. The first example is used in Connecticut, and the second example is used in Sweden.
  2. When a fibroid has calcifications it has been there a long time, and can be assumed to be benign.
  3. Chorionic villi are promiscuous contaminants of other tissues, and may cause a false positive finding for another cassette containing products of conception.
    - Carll T, Fuja C, Antic T, Lastra R, Pytel P (2022). "Tissue Contamination During Transportation of Formalin-Fixed, Paraffin-Embedded Blocks. ". Am J Clin Pathol 158 (1): 96-104. doi:10.1093/ajcp/aqac014. PMID 35195717. Archived from the original. . 
  4. For a case with intra-fallopian coils in the medical records, an inability to find them on gross processing must be noted in order to raise the possibility of coil expulsion.

Main page

References

  1. Rao, Shalinee; Sundaram, Sandhya; Narasimhan, Raghavan (2009). "Biological behavior of preneoplastic conditions of the endometrium: A retrospective 16-year study in south India ". Indian Journal of Medical and Paediatric Oncology 30 (4): 131. doi:10.4103/0971-5851.65335. ISSN 0971-5851. 
    - Figure- available via license: Creative Commons Attribution 2.0 Generic
  2. 2.0 2.1 2.2 Owings, Richard A.; Quick, Charles M. (2014). "Endometrial Intraepithelial Neoplasia ". Archives of Pathology & Laboratory Medicine 138 (4): 484–491. doi:10.5858/arpa.2012-0709-RA. ISSN 1543-2165. 
  3. Stewart, Colin J.R.; Crum, Christopher P.; McCluggage, W. Glenn; Park, Kay J.; Rutgers, Joanne K.; Oliva, Esther; Malpica, Anais; Parkash, Vinita; et al. (2019). "Guidelines to Aid in the Distinction of Endometrial and Endocervical Carcinomas, and the Distinction of Independent Primary Carcinomas of the Endometrium and Adnexa From Metastatic Spread Between These and Other Sites ". International Journal of Gynecological Pathology 38: S75–S92. doi:10.1097/PGP.0000000000000553. ISSN 0277-1691. 
    - "Figures - available via license: Creative Commons Attribution 4.0 International"
  4. 4.0 4.1 4.2 Rabban, Joseph T.; Gilks, C. Blake; Malpica, Anais; Matias-Guiu, Xavier; Mittal, Khush; Mutter, George L.; Oliva, Esther; Parkash, Vinita; et al. (2019). "Issues in the Differential Diagnosis of Uterine Low-grade Endometrioid Carcinoma, Including Mixed Endometrial Carcinomas ". International Journal of Gynecological Pathology 38: S25–S39. doi:10.1097/PGP.0000000000000512. ISSN 0277-1691. 
  5. Nicole Cipriani (2020-06-22). Gross Pathology Manual. The University of Chicago Department of Pathology.
  6. Rao, Shalinee; Sundaram, Sandhya; Narasimhan, Raghavan (2009). "Biological behavior of preneoplastic conditions of the endometrium: A retrospective 16-year study in south India ". Indian Journal of Medical and Paediatric Oncology 30 (4): 131. doi:10.4103/0971-5851.65335. ISSN 0971-5851. 
    - Figure- available via license: Creative Commons Attribution 2.0 Generic
  7. Stewart, Colin J.R.; Crum, Christopher P.; McCluggage, W. Glenn; Park, Kay J.; Rutgers, Joanne K.; Oliva, Esther; Malpica, Anais; Parkash, Vinita; et al. (2019). "Guidelines to Aid in the Distinction of Endometrial and Endocervical Carcinomas, and the Distinction of Independent Primary Carcinomas of the Endometrium and Adnexa From Metastatic Spread Between These and Other Sites ". International Journal of Gynecological Pathology 38: S75–S92. doi:10.1097/PGP.0000000000000553. ISSN 0277-1691. 
    - "Figures - available via license: Creative Commons Attribution 4.0 International"
  8. 8.0 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 8.9 Monica Dahlgren, Janne Malina, Anna Måsbäck, Otto Ljungberg. Stora utskärningen. KVAST (Swedish Society of Pathology). Retrieved on 2019-09-26.
  9. 9.0 9.1 . General Specimen Orientation Tips. The University of Michigan (2020-01-29).
  10. Nicole Cipriani (2020-06-22). Gross Pathology Manual. The University of Chicago Department of Pathology.
  11. Khaled J. Alkhateeb, M.B.B.S., Ziyan T. Salih, M.D.. HSIL / CIN II / CIN III. PathologyOutlines. Topic Completed: 29 March 2021. Minor changes: 9 February 2022
  12. Source image by Ed Uthman from Houston, TX, USA. Creative Commons Attribution 2.0 Generic (CC BY 2.0) license
  13. Anissa Ben Amor.. Cervical Ectropion. StatPearls, National Center for Biotechnology Information. Last Update: November 14, 2021.
    - This book is distributed under the terms of the Creative Commons Attribution 4.0 International License
  14. Rao, Shalinee; Sundaram, Sandhya; Narasimhan, Raghavan (2009). "Biological behavior of preneoplastic conditions of the endometrium: A retrospective 16-year study in south India ". Indian Journal of Medical and Paediatric Oncology 30 (4): 131. doi:10.4103/0971-5851.65335. ISSN 0971-5851. 
    - Figure- available via license: Creative Commons Attribution 2.0 Generic
  15. Stewart, Colin J.R.; Crum, Christopher P.; McCluggage, W. Glenn; Park, Kay J.; Rutgers, Joanne K.; Oliva, Esther; Malpica, Anais; Parkash, Vinita; et al. (2019). "Guidelines to Aid in the Distinction of Endometrial and Endocervical Carcinomas, and the Distinction of Independent Primary Carcinomas of the Endometrium and Adnexa From Metastatic Spread Between These and Other Sites ". International Journal of Gynecological Pathology 38: S75–S92. doi:10.1097/PGP.0000000000000553. ISSN 0277-1691. 
    - "Figures - available via license: Creative Commons Attribution 4.0 International"
  16. 16.0 16.1 Paulette Mhawech-Fauceglia, M.D.. Uterus - Smooth muscle tumors - Leiomyosarcoma. Pathology Outlines. Topic Completed: 5 December 2019. Minor changes: 11 August 2020
  17. Mohamed Mokhtar Desouki. Uterus - Stromal tumors - Leiomyoma. Pathology Outlines. Topic Completed: 1 August 2011. Revised: 15 December 2019
  18. Vijay Shankar, M.D.. Soft tissue - Smooth muscle - Leiomyosarcoma - general. Pathology Outlines. Topic Completed: 1 November 2012. Revised: 11 September 2019
  19. 19.0 19.1 . Gross Pathology Manual, By The University of Chicago Department of Pathology - Products of Conception. Retrieved on 2020-08-13.
  20. Konoplev SN, Dimashkieh HH, Stanek J (2004). "Cytokeratin immunohistochemistry: a procedure for exclusion of pregnancy in chorionic villi-negative specimen. ". Placenta 25 (2-3): 146-52. doi:10.1016/S0143-4004(03)00188-7. PMID 14972447. Archived from the original. . 
  21. 21.0 21.1 Kerryn Ireland-Jenkin and Marsali Newman. Ovary and fallopian tube -benign setting. Royal College of Pathologists of Australasia. Retrieved on 2020-10-16.
  22. Crum, Christopher P.; Mckeon, Frank D.; Xian, Wa (2012). "The Oviduct and Ovarian Cancer ". Clinical Obstetrics and Gynecology 55 (1): 24–35. doi:10.1097/GRF.0b013e31824b1725. ISSN 0009-9201. 
  23. 23.0 23.1 Nicole Riddle, Jamie Shutter. Fallopian tubes & broad ligament - Fallopian tube tumors - Adenomatoid tumor. Pathology Outlines. Topic Completed: 1 September 2013. Minor changes: 13 December 2019

Image sources

Ovary

Gross processing

"Long" and "short" axis.[1]

The ovary is cut in the longitudinal plane (through the "long axis").

Ovaries, including those with cysts, are almost never inked.

Gross report

Template:

(A. Labeled - __. The specimen is received in formalin and consists of) an ovary measuring ___. The ovarian capsule is tan-pink and smooth. Cut sections reveal solid, white and whorled parenchyma, and no gross lesions. Representative sections are submitted for microscopic examination in __ cassettes.

Microscopic examination

Signet ring cell carcinoma metastasis to the ovary, also called Krukenberg tumor: Gross pathology (top, cross-section at right) and histopathology at low and high magnification.[2]

Apart from any obvious tumor, also look for signet ring cells, which is a major feature of metastatic tumors to the ovary.


Placenta

Gross processing

  • Determine the shape of the placenta
  • Look for any accessory lobes
  • Determine the completeness of placental membranes, opacity, color and consistency (slimy/slippery?)
  • Determine the point of rupture from nearest margin
  • Note where the membranes are inserted
  • Examine the umbilical cord
  • Measure the distance between the insertion point and the nearest placental margin
  • Measure the cord length and give proximal and distal diameter. In placental pathology, the proximal umbilical cord refers to the segment closest to the placenta, and distal is the segment closest to the fetus.[note 1]
  • Count the number of vessels away from the insertion
  • Weigh the trimmed disk, after having trimmed away the cord and membranes, and after having removed excess amounts of loose retroplacental blood clots over the maternal surface.
  • Examine the fetal surface (chorionic plate):
  • Note its color, in particular if it is green (often faint and tan-green, brown-green to yellow-green (which indicates meconium staining).
  • Look for any pathologies including granular excrescences, subchorionic fibrin or subamniotic hemorrhage
  • Look at the integrity and extent of the vasculature, including any traumatic damage. Also palpate the vasculature for any thrombosis. If a thrombus is grossly found for a live birth, the baby may have thrombosis, so the finding must immediately be reported to the clinician in care of the baby.
  • Examine the maternal surface (basal plate) for completeness, adherent blood clots, depressions, calcifications and fibrin
  • Take a membrane roll and cord sections, before sectioning the placenta
  • With the fetal surface down on the cutting board, cut the placenta at 1cm intervals so that it can be reconstructed.
  • Palpate the parencyhmal sections for areas of induration.
  • Note the color of the parenchyma and describe any pale areas, cysts, thrombi, increased fibrin, calcifications and infarcts. For possible infarcts, estimate the total amount of infarcted tissue as a percentage of the placental volume. Infarction is clinically significant if it involves at least 5-10% of the placental volume.
Gross pathology of placental disorders.[3]

If you see a true knot (rather than "false knots" which are merely bulges or protuberances that may look like knots), report whether the diameter of the cord is significantly different before versus after the knot (which is a sign of constriction caused by the knot).

Tissue selection

  • Distal (toward fetus) membrane roll and cross section of distal cord. It should include the area of rupture.
  • Proximal (toward placenta) membrane roll and cross section of proximal cord ( 2-3 cm from insertion). They should include membranes up to the chorionic plate.

A membrane roll is created by cutting a strip, about 3 cm wide, of membrane, from the rupture site to the placental insertion. Hold the edge with forceps and roll it around the forceps, and then cut a transverse section of the roll.
Cord sections should be no thicker than 4mm.

  • Placental section including fetal surface ( full thickness if possible)
  • Placental section including maternal surface (full thickness if possible)
  • Any lesions or abnormalities

Avoid taking placental sections near the margin. (If transported or processed together with other cases, put the placental in thin-mesh cassettes or tissue bags to limit contamination).[note 2]

Example report:

Container A. Labeled "bladder tumor". The specimen is received in formalin and consists of multiple fragments of tan-gray, friable soft tissue measuring about __ x __ x __ cm in aggregate. The specimen is entirely submitted for microscopic examination in __ cassettes.

Gross report

Placenta weight by gestational age.

Example in a normal case:

(A. Labeled with patient's name and medical record number. The specimen is received fresh and consists of a) placenta with attached membranes and umbilical cord. The membranes are tan-red( with a marginal insertion. The site of rupture is __ cm from the nearest placental margin. There is no accessory lobe.) The trimmed placental weight is __ gramsTemplate:Comprehensive-begin-Corresponding to the __th percentile for the gestational age)). The placental disc measures __ cm and varies in thickness from __ to __ cm. The umbilical cord is tan-pink and eccentrically inserted(, __ cm from the nearest placental margin, and measures __ cm in length, __ cm in proximal diameter and __ cm in distal diameter.) Cut sections of the cord reveal three blood vessels. The fetal surface is blue-pink, smooth with normal vasculature and << minimal / moderate / major>> subchorionic fibrin deposition. The maternal surface is complete with <<minimal / moderate / major>> physiologic calcifications. Sectioning reveals a red, spongy, homogenous parenchyma without gross lesions. (Representative sections are submitted for microscopic examination in 4 cassettes.)

KEY OF SECTIONS (example):

  • 1- distal membranes and umbilical cord
  • 2- proximal membranes and umbilical cord
  • 3- placental section including fetal surface
  • 4- placental section including maternal surface

Microscopic examination

  • Look for inflammation, especially by the fetal surface in the intervillous spaces and around the fetal blood vessels.
  • At least if there is a suspicion of meconium in the amniotic fluid (from clinical history and/or the gross exam), look for the following histopathologic signs of it:[5]

Other relatively common findings

Microscopy report

Generally, also include major gross findings, such as an area of placental abruption.

Example of normal report:

(Placenta, <<vaginal/Caesarean>> delivery:)
Third trimester placenta with term villous histology. Placental weight (__ gm), at __th percentile for gestational age. Membranes without significant histopathologic changes((, negative for chorioamnionitis)). Trivascular umbilical cord, with no significant histopathologic changes((, negative for funisitis)).

Mild to moderate inflammation in the decidua alone can be ignored (as it is most commonly a physiological response and doesn't have a clinical significance for the fetus).

Example in a twin placenta:

Twin placenta, Caesarean section:
  • Third trimester dichorionic, diamniotic twin placenta.
  • Villous morphology histologically appropriate for gestational age.
  • Placental weight approximately 25th percentile for gestational age.
  • Two three-vessel umbilical cords.
  • Negative for chorioamnionitis and funisitis.


Vulva

Gross processing

Generally as per skin.

Microscopic examination

Histopathology of high-grade squamous intraepithelial lesion (HSIL) of vulva (left in image) with full thickness dysplasia, compared to normal epithelium at right.

Mainly look for squamous vulvar intraepithelial lesions:

  • Low-grade squamous intraepithelial lesion (LSIL):[8]
  • Acanthosis, papillomatosis, and/or atypical koilocytosis in upper layers
  • Usually mild atypia and mitoses, limited to the lower third of stratum spinosum and basale
  • Binucleated epithelial cells
  • High-grade squamous intraepithelial lesion (HSIL):[8]
  • Enlarged atypical nuclei and mitoses involving middle and upper third of the epithelium.
  • Also telling are atypical mitoses and/or extension in hair follicles and skin appendages.

Staging of vulvar cancer

Tumors of the vulva are staged as per the AJCC, 8th Ed:[9]

Primary tumor (T)
TNM FIGO Criteria
TX Primary tumor cannot be assessed
T0 No evidence of a primary tumor
Tisa Carcinoma in situ (preinvasive)
T1a IA Lesions ≤2 cm, confined to the vulva or perineum and with stromal invasion ≤1 mmb
T1b IB Lesions >2 cm or any size with stromal invasion >1 mm, confined to the vulva or perineum
T2 II Tumor of any size with extension to adjacent perineal structures (distal third of the urethra, distal third of the vagina, anal involvement)
T3 IVA Tumor of any size with extension to any of the following proximal two thirds of the urethra, proximal two thirds of the vagina, bladder mucosa, or rectal mucosa or fixed to pelvic bone
Regional lymph nodes (N)
TNM FIGO Criteria
NX Regional lymph nodes cannot be assessed
N0 No regional lymph node metastasis
N1 1 or 2 regional (inguinofemoral) lymph nodes with the following features (see N1a, N1b)
N1a IIIA 1 or 2 lymph node metastases, each < 5 mm
N1b IIIA 1 regional lymph node metastasis ≥5 mm
N2 Regional (inguinofemoral) lymph nodes with the following features (see N2a, N2b, N2c)
N2a IIIB 3 or more lymph node metastases, each < 5 mm
N2b IIIB 2 or more regional lymph node metastases ≥5 mm
N2c IIIC Regional lymph node metastasis with extracapsular spread
N3 IVA Fixed or ulcerated regional lymph node metastasis
Distant metastasis (M)
TNM FIGO Criteria
M0 No distant metastasis
M1 IVB Distant metastasis (including to pelvic lymph nodes)


Cervical cytology

Clinical information

It is not necessary to look through more than readily available reports from previous cervical cytologies.

Magnification

While being fairly new to cervical cytology, preferably start looking at a high magnification such as 20x objective (with 10x eye piece). For suspicious findings, you may magnify up to maximum. On the other hand, once the pattern feels repetitive you can try switching to a slightly lower magnification such as 10x.

Adequacy

Adequacy should always be stated, either as "Satisfactory" or "Unsatisfactory". For estimating the number of cells, determine the following:

  • The area of your field of view at high power (see the Evaluation chapter)
  • The total size of the relevant area on the microscope slide. A ThinPrep is about 360 mm2.
  • Look at 10 representative high power fields (HPFs) within that area, and calculate the average number of cells per high power field.
HPF example on a ThinPrep (about 360 mm2). If 10 fields gives a total of 40 cells, it will be 4 cells per HPF. The area of this field is 0.23 mm2. Therefore, total cellularity is estimated to be:
4 cells * 360mm2 / 0.23mm2 = 6260 cells.
Total number of cells = Average number of cells per HPF * Total size of area
HPF area

Conventional smear cellularity should be at least 8,000 cells. Liquid-based cytology cellularity should be at least 5,000 cells. Also a conventional smear is inadequate if >75% of cells are obscured by blood, exudate or air-drying artefact.[10]

Eventually you will be able to tell when most cases are adequate or inadequate without performing a detailed calculation.

Transformation zone presence

Squamous metaplasia also counts as endocervix. Typical features are annotated. Pap stain.

State whether the endocervical/transformation zone is present or absent. Count an endocervical component as present if there are 10 or more endocervical or squamous metaplastic cells.[11]

In patients with previous hysterectomy, simply report glandular or squamous metaplastic cells as such, rather than stating the presence of a transformation zone, since they are likely vaginal in origin in such patients.[12]

Very common findings

Main conditions to exclude or confirm

Squamous atypia, seen mainly as cells with increased nucleus/cytoplasm ratio, nuclear hyperchromasia and irregular nuclear outline.

Cytopathology of squamous cell carcinoma, nonkeratinizing variant, with typical features.[14] Pap stain. Necrotic debris (dirty background) is a feature that generally makes a HSIL case "suspicious for invasive squamous cell carcinoma".[15] In contrast to the more distinct keratinizing variant, these findings are overall less specific, and most can be seen in other cancers such as adenocarcinoma as well (which, however, tends to have fine chromatin)[16]

Clinical implication

If you are uncertain of the degree of dysplasia, it can be useful to look up how much difference it will likely make for the management of the patient. You may make an Internet search for the management of abnormal cervical screening in your region (such as The ASCCP tool for management in the US). A change from close follow-up to colposcopy is not that big of a deal, but if one of the alternatives will lead to a diagnostic excision, make sure that the case is looked upon by commensurate expertise.


Report

Example in a normal case:

Cervical/endocervical ThinPrep:
Negative for intraepithelial lesion or malignancy (NILM).


Male reproductive system

Phimosis

Gross processing

Generally sample one or two representative sections in a cassette, in addition to sections of any grossly visible lesions.

  See also: General notes on gross processing

Microscopic evaluation

Look for:

Optionally, note any sclerosis and/or fibrosis.

Reporting

  • Description of objective findings, and any suspected underlying disease.
  • Presence or absence of dysplasia.


Vas deferens

Gross processing in sterilization

In sterilization:[19]

  • Measure length and diameter.
  • Serially section
  • Submit 2 cross sections measuring 5 mm in length.

Communicate to the histology lab to section the specimen as tubular structures, in order to get proper cross-sections.

Microscopic examination in sterilization

Confirm that there is a complete cross-section from each side. Example images of normal vas deferens:

Report

Example report:

Right and left vas deferens segments, excisions:
Complete cross-sections of vasa deferentia without significant histopathologic changes.


Skin

Suspected malignant skin excisions

Author: Mikael Häggström [note 3]
Suspected malignant skin excisions:

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Common targets

If directly suspected from the referral, see:

  • Melanoma

Gross processing

Gross examination

Note:

  • Color
  • Well-defined or diffuse border
  • Size
  • Any elevation

Tissue selection

Tissue selection from suspected malignant skin lesions, by lesion size:[21][note 4]
<4 mm 4 - 8 mm 9 - 15 mm
Tissue selection from skin excision with less than 4 mm suspected malignant lesion.png Tissue selection from skin excision with 4-8 mm suspected malignant lesion.png Tissue selection from skin excision with 9-15 mm suspected malignant lesion.png

In table above, each top image shows recommended lines for cutting out slices to be submitted for further processing. Bottom image shows which side of the slice that should be put to microtomy. Dashed lines here mean that either side could be used. Further information: Gross processing of skin excisions

Microscopic evaluation

If the lesion was pigmented on gross examination, evaluate as a dark skin focality. If not:

Look for atypical cells, possibly by scrolling through the epidermis at intermediate magnification and then through the dermis at a lower magnification. If atypical cells are found, look for:

  • Similarity to squamous cells: See below:

Squamous cell-like skin proliferations: Differential diagnosis

Main differential diagnoses and their characteristics:[22]

General benign imitators of skin malignancy

Further workup of malignant findings

In case of skin cancer, determine whether the peripheral/radial and deep margins are clear, close or continuous.[23][note 7] A close margin has various definitions for different malignancies, but for basal-cell carcinoma and cutaneous squamous cell carcinoma it is defined as being closer than 1 mm from the edge (but yet non-continuous with it),[23][24] but 2-3 mm for melanoma.[25]

Previous biopsy

(At least if there is a known previous biopsy, look for changes that are consistent with a biopsy site, to confirm that it was taken from the excised area.) Such changes in the skin include:

  • Granulation tissue in more fresh biopsies
  • Dense collagen
  • Fibrosis with vertical blood vessels
  • Fibrosis that replaces solar elastosis

Reporting

Preferably see specific article on the condition at hand, if available.

  • Optionally, the presence of a keratinized squamous epithelium.
  • Any abnormalities, generally preceded by location in terms of epidermal, dermal or more specific layers thereof.
  • If malignant:
  • Degree of differentiation
  • Radicality, mainly into either of the following: edit
  • >___ mm (Definitions vary for the distance as per Further workup of malignant findings above): "Clear margins" (or: "Clear margins at over __ mm")((or the exact distance thereof)).))
  • <___ mm but not continuous with edge: "Close margins at __ mm at (location). [[Locations are mainly the deep edge, or the (superior/inferior/medial/lateral) radial edge.]]." Numbers are generally given at an exactness of 0.1 mm.[23]
  • Continuous with margin: "Not radically excised at (location)."
For skin shave biopsies, non-radicality may be reported as: "Extending to base and peripheral edges of biopsy" (as they may not be regarded as "margins" on a biopsy).
  • Perineural or vascular invasion if present.

Notes

  1. In contrast, in embryology and fetal medicine, the proximal umbilical cord refers to the segment closest to the fetus:
    - Wyburn GM (1939). "The formation of the umbilical cord and the umbilical region of the anterior abdominal wall. ". J Anat 73 (Pt 2): 289-310.9. PMID 17104757. PMC: 1252509. Archived from the original. . 
    Harvey J. Kliman, M.D., Ph.D. (2006-10-29). The Umbilical Cord (from The Encyclopedia of Reproduction). Yale School of Medicine.
  2. Chorionic villi are promiscuous contaminants of other tissues, and may cause a false positive finding for a cassette containing products of conception.
    - Carll T, Fuja C, Antic T, Lastra R, Pytel P (2022). "Tissue Contamination During Transportation of Formalin-Fixed, Paraffin-Embedded Blocks. ". Am J Clin Pathol 158 (1): 96-104. doi:10.1093/ajcp/aqac014. PMID 35195717. Archived from the original. . 
  3. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  4. The excision example shows a superficial basal cell carcinoma.
  5. - Buschke–Löwenstein tumor is an alternative name for verrucous squamous cell carcinoma in the ano-genital region.
    - Carcinoma cuniculatum is a characteristic form of verrucous squamous cell carcinoma on the sole.
  6. Inverted follicular keratosis is generally thought to be a rare variant of seborrheic keratosis, but this position is not universally accepted.
    - Karadag, AyseSerap; Ozlu, Emin; Uzuncakmak, TugbaKevser; Akdeniz, Necmettin; Cobanoglu, Bengu; Oman, Berkant (2016). "Inverted follicular keratosis successfully treated with imiquimod ". Indian Dermatology Online Journal 7 (3): 177. doi:10.4103/2229-5178.182354. ISSN 2229-5178. 
  7. "Peripheral" or "radial" margins are preferred rather than "lateral", since a "lateral" margin may be interpreted as opposite to the "medial margin".

Main page

References

  1. Pellerito, John; Polak, Joseph F. (2012). Introduction to Vascular Ultrasonography (6th ed.). Elsevier Health Sciences. p. 559. ISBN 978-1-4557-3766-6. 
  2. Nakamura, Yoshiaki; Hiramatsu, Ayako; Koyama, Takafumi; Oyama, Yu; Tanaka, Ayuko; Honma, Koichi (2014). "A Krukenberg Tumor from an Occult Intramucosal Gastric Carcinoma Identified during an Autopsy ". Case Reports in Oncological Medicine 2014: 1–5. doi:10.1155/2014/797429. ISSN 2090-6706. 
    - Creative Commons Attribution 3.0 Unported (CC BY 3.0) license
  3. Chen, Yukun; Zhang, Zhuomin; Wu, Chenyan; Davaasuren, Dolzodmaa; Goldstein, Jeffery A.; Gernand, Alison D.; Wang, James Z. (2020). "AI-PLAX: AI-based placental assessment and examination using photos ". Computerized Medical Imaging and Graphics 84: 101744. doi:10.1016/j.compmedimag.2020.101744. ISSN 08956111. 
    - Fig 5- available via license: Creative Commons Attribution 4.0 International.
  4. Kim, Chong Jai; Romero, Roberto; Chaemsaithong, Piya; Chaiyasit, Noppadol; Yoon, Bo Hyun; Kim, Yeon Mee (2015). "Acute chorioamnionitis and funisitis: definition, pathologic features, and clinical significance ". American Journal of Obstetrics and Gynecology 213 (4): S29–S52. doi:10.1016/j.ajog.2015.08.040. ISSN 00029378. 
  5. Mandolin S. Ziadie. Placenta - Nonneoplastic placental conditions and abnormalities - Noninfectious - Meconium staining. Pathology Outlines. Topic Completed: 1 October 2011. Minor changes: 27 August 2020
  6. Chapter 3. Placental Calcification: Its Processes and Impact on Pregnancy, Kachewar, Sushil (2013). Calcification : processes, determinants and health impact . New York: Nova Science Publishers, Inc. ISBN 978-1-62618-155-7. OCLC 840507829. 
  7. Heazell AE, Moll SJ, Jones CJ, Baker PN, Crocker IP (2007). "Formation of syncytial knots is increased by hyperoxia, hypoxia and reactive oxygen species. ". Placenta 28 Suppl A: S33-40. doi:10.1016/j.placenta.2006.10.007. PMID 17140657. Archived from the original. . 
  8. 8.0 8.1 Matthias Choschzick. Vulva, vagina & female urethra - Squamous carcinoma and precursor lesions - HPV associated SIL. PathologyOutlines. Topic Completed: 6 January 2021. Minor changes: 11 June 2021
  9. Amin, Mahul (2017). AJCC cancer staging manual (8 ed.). Switzerland: Springer. ISBN 978-3-319-40617-6. OCLC 961218414. 
    - For access, see the Secrets chapter of Patholines.
    - Copyright note: The AJCC, 8th Ed. is published by a company in Switzerland, and the tables presented therein are Public Domain because they consist of tabular information without literary or artistic innovation, and therefore do not fulfil the inclusion criterion of the Swiss Copyright Act (CopA) which applies to "literary and artistic intellectual creations with individual character" (see Federal Act on Copyright and Related Rights (Copyright Act, CopA) of 9 October 1992 (Status as of 1 January 2022)). edit
  10. 10.0 10.1 . Criteria for adequacy of a cervical cytology sample. EuroCytology. Retrieved on 2022-08-29.
  11. Cibas, Edmund S.; Ducatman, Barbara S. (2021). Cytology : diagnostic principles and clinical correlates . Philadelphia, PA. p. 9. ISBN 978-0-323-63637-7. OCLC 1138033641. 
  12. Ramirez NC, Sastry LK, Pisharodi LR (2000). "Benign glandular and squamous metaplastic-like cells seen in vaginal Pap smears of post hysterectomy patients: incidence and patient profile. ". Eur J Gynaecol Oncol 21 (1): 43-8. PMID 10726617. Archived from the original. . 
  13. - Image annotated by Mikael Häggström
    - Reference for entries: Gulisa Turashvili, M.D., Ph.D.. Cervix - Squamous cell carcinoma and variants. Pathology Outlines. Last author update: 24 September 2020. Last staff update: 4 April 2022.
    - Source image from National Cancer Institute (Public Domain)
  14. - Image annotated by Mikael Häggström
    - Reference for entries: Gulisa Turashvili, M.D., Ph.D.. Cervix - Squamous cell carcinoma and variants. Pathology Outlines. Last author update: 24 September 2020. Last staff update: 4 April 2022.
    - Source image by Ravi Mehrotra, Anurag Gupta, Mamta Singh and Rahela Ibrahim (Creative Commons Attribution 2.0 Generic license.)
  15. Alrajjal A, Pansare V, Choudhury MSR, Khan MYA, Shidham VB (2021). "Squamous intraepithelial lesions (SIL: LSIL, HSIL, ASCUS, ASC-H, LSIL-H) of Uterine Cervix and Bethesda System. ". Cytojournal 18: 16. doi:10.25259/Cytojournal_24_2021. PMID 34345247. PMC: 8326095. Archived from the original. . 
  16. Authors: Caroline I.M. Underwood, M.D., Alexis Musick, B.S., Carolyn Glass, M.D., Ph.D.. Adenocarcinoma overview. Pathology Outlines. Last staff update: 19 July 2022
  17. Clemmensen, Ole J.; Krogh, John; Petri, Michael (1988). "The Histologic Spectrum of Prepuces from Patients with Phimosis ". The American Journal of Dermatopathology 10 (2): 104–108. doi:10.1097/00000372-198804000-00002. ISSN 0193-1091. 
  18. Alcides Chaux, Antonio L. Cubilla. Penis and scrotum - Inflammatory lesions - Phimosis. PathologyOutlines. Topic Completed: 1 February 2010. Revised: 13 February 2019
  19. . Vas Deferens (Sterilization). Gross Pathology Manual - By The University of Chicago Department of Pathology. Retrieved on 2021-08-27.
  20. Vas deferens image available in Public Domain. See https://patholines.org/File:Vas_deferens.jpg
  21. There are many variants for the processing of skin excisions. These examples use aspects from the following sources: ". Ochsner J 5 (2): 22–33. 2003. PMID 22826680. PMC: 3399331. Archived from the original. . 
    - With a "standard histologic examination" that, in addition to the lesion, only includes one section from each side along the longest diameter of the specimen.
    - It also shows an example of circular coverage, with equal coverage distance in all four directions.
    - The entire specimen may be submitted if the risk of malignancy is high.
  22. Initially copied from: Paolino, Giovanni; Donati, Michele; Didona, Dario; Mercuri, Santo; Cantisani, Carmen (2017). "Histology of Non-Melanoma Skin Cancers: An Update ". Biomedicines 5 (4): 71. doi:10.3390/biomedicines5040071. ISSN 2227-9059. 
    "This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)."
  23. 23.0 23.1 23.2 David Slater, Paul Barrett. Standards and datasets for reporting cancers - Dataset for histopathological reporting of primary cutaneous basal cell carcinoma. The Royal College of Pathologists. February 2019
  24. 1 mm as cutoff for close margin: Brodie M Elliott, Benjamin R Douglass, Daniel McConnell, Blair Johnson, Christopher Harmston (2018-12-14). New Zealand Medical Journal.
  25. Page 406 in: Klaus J. Busam, Richard A Scolyer, Pedram Gerami (2018). Pathology of Melanocytic Tumors . Elsevier Health Sciences. ISBN 9780323508681. 

Image sources

Basal-cell carcinoma

Author: Mikael Häggström [note 1]

Nodular basal-cell carcinoma.

Basal-cell carcinoma (BCC):

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Gross processing

Gross examination

Note:

  • Color
  • Well-defined or diffuse border
  • Size
  • Any elevation

Tissue selection

Tissue selection from suspected malignant skin lesions, by lesion size:[1][note 2]
<4 mm 4 - 8 mm 9 - 15 mm
Tissue selection from skin excision with less than 4 mm suspected malignant lesion.png Tissue selection from skin excision with 4-8 mm suspected malignant lesion.png Tissue selection from skin excision with 9-15 mm suspected malignant lesion.png

In table above, each top image shows recommended lines for cutting out slices to be submitted for further processing. Bottom image shows which side of the slice that should be put to microtomy. Dashed lines here mean that either side could be used. Further information: Gross processing of skin excisions

Microscopic evaluation

Broadly consists of determining the following:

  • Whether it is basal-cell carcinoma or a differential diagnosis.
  • Aggressiveness pattern
  • Radicality

Optionally, further subtyping of basal-cell carcinoma can be made.

Characteristics

Basal-cell carcinomas may be pigmented as shown (but consider the possibility of melanoma in such cases).

In uncertain cases, immunohistochemistry using BerEP4 can be used, having a high sensitivity and specificity in detecting only BCC cells.[3]

Differential diagnoses

Main histological differential diagnoses of basal cell carcinoma:

Hair follicles

The edges of hair follicle cells may resemble palisades, but are less pronounced, and are generally more diffusely delineated compared to surroundings.

Squamous-cell carcinoma

Squamous-cell carcinoma of the skin is generally distinguishable by for example relatively more cytoplasm, horn cyst formation and absence of palisading and cleft formations.

edit

Yet, a high prevalence means a relatively high incidence of borderline cases. In such cases, look particularly at the surface and attempt to classify as either of the following:

In unclear cases, the most useful immunohistochemistry marker appears to be MOC-31, which essentially always stains metatypical basal-cell carcinomas but not basaloid squamous-cell carcinomas.[5] UEA-1 appears to be the second most useful marker, staining almost all basaloid squamous-cell carcinomas but only a few metatypical basal-cell carcinomas.[5]

Others[6]

Aggressiveness

Aggressiveness can be classified as low-level aggressive, moderately aggressive and highly aggressive, based mainly the cohesion of cancer cells, but also upon other histopathologic subtypes:

Low-level aggressive patterns
Moderately aggressive pattern
Highly aggressive patterns

Radicality

Determine if there are basal-cell formations continuous with resection margins, or if they are closer or farther than 1 mm from the closest edge.[10] If closer, measure the distance.

If uncertain, immunohistochemistry with BerEP4 helps in distinguishing the BCC cells.

Comparison H&E stain (left) with BerEP4 immunohistochemistry staining (right) on a pathological section having BCC with squamous cell metaplasia. Only BCC cells are stained with BerEP4.[3]
Further information: Evaluation of tumors

Reporting

  • Aggressiveness pattern, at least if highly aggressive.
  • Radicality, mainly into either of the following: edit
  • >1 mm (as per Radicality above): "Clear margins" (or: "Clear margins at over __ mm")((or the exact distance thereof)).))
  • <1 mm but not continuous with edge: "Close margins at __ mm at (location). [[Locations are mainly the deep edge, or the (superior/inferior/medial/lateral) radial edge.]]." Numbers are generally given at an exactness of 0.1 mm.[10]
  • Continuous with margin: "Not radically excised at (location)."

Optionally, subtype of basal-cell carcinoma

Example:

Non-radical basal-cell cancer.jpg
(Skin excision with stratified squamous keratinized epithelium, where the dermis contains) moderately aggressive basal-cell carcinoma, not radically excised at the right margin.[note 4]
  See also: General notes on reporting

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. The excision example shows a superficial basal cell carcinoma.
  3. Desmoplastic tricoepithelioma is particularly similar to basal-cell carcinoma.
  4. The direction was known from needle marking.

Main page

References

  1. There are many variants for the processing of skin excisions. These examples use aspects from the following sources: ". Ochsner J 5 (2): 22–33. 2003. PMID 22826680. PMC: 3399331. Archived from the original. . 
    - With a "standard histologic examination" that, in addition to the lesion, only includes one section from each side along the longest diameter of the specimen.
    - It also shows an example of circular coverage, with equal coverage distance in all four directions.
    - The entire specimen may be submitted if the risk of malignancy is high.
  2. Robert S Bader. Which histologic findings are characteristic of basal cell carcinoma (BCC)?. Medscape. Updated: Feb 21, 2019
  3. 3.0 3.1 Sunjaya, Anthony Paulo; Sunjaya, Angela Felicia; Tan, Sukmawati Tansil (2017). "The Use of BEREP4 Immunohistochemistry Staining for Detection of Basal Cell Carcinoma ". Journal of Skin Cancer 2017: 1–10. doi:10.1155/2017/2692604. ISSN 2090-2905. 
  4. El-Mofty, SK. (2014). "Histopathologic risk factors in oral and oropharyngeal squamous cell carcinoma variants: An update with special reference to HPV-related carcinomas ". Medicina Oral Patología Oral y Cirugia Bucal: e377–e385. doi:10.4317/medoral.20184. ISSN 16986946. 
    License: CC BY 2.5
  5. 5.0 5.1 Webb, David V.; Mentrikoski, Mark J.; Verduin, Lindsey; Brill, Louis B.; Wick, Mark R. (2015). "Basal cell carcinoma vs basaloid squamous cell carcinoma of the skin: an immunohistochemical reappraisal ". Annals of Diagnostic Pathology 19 (2): 70–75. doi:10.1016/j.anndiagpath.2015.01.004. ISSN 10929134. 
  6. 6.0 6.1 6.2 6.3 6.4 Paolino, Giovanni; Donati, Michele; Didona, Dario; Mercuri, Santo; Cantisani, Carmen (2017). "Histology of Non-Melanoma Skin Cancers: An Update ". Biomedicines 5 (4): 71. doi:10.3390/biomedicines5040071. ISSN 2227-9059. 
  7. Inskip, Mike; Magee, Jill (2015). "Microcystic adnexal carcinoma of the cheek—a case report with dermatoscopy and dermatopathology ". Dermatology Practical & Conceptual 5 (1). doi:10.5826/dpc.0501a07. ISSN 21609381. 
  8. Yonan, Yousif; Maly, Connor; DiCaudo, David; Mangold, Aaron; Pittelkow, Mark; Swanson, David (2019). "Dermoscopic Description of Fibroepithelioma of Pinkus with Negative Network ". Dermatology Practical & Conceptual: 246–247. doi:10.5826/dpc.0903a23. ISSN 2160-9381.  Creative Commons Attribution License
  9. East, Ellen; Fullen, Douglas R.; Arps, David; Patel, Rajiv M.; Palanisamy, Nallasivam; Carskadon, Shannon; Harms, Paul W. (2016). "Morpheaform Basal Cell Carcinomas With Areas of Predominantly Single-Cell Pattern of Infiltration ". The American Journal of Dermatopathology 38 (10): 744–750. doi:10.1097/DAD.0000000000000541. ISSN 0193-1091. 
  10. 10.0 10.1 David Slater, Paul Barrett. Standards and datasets for reporting cancers - Dataset for histopathological reporting of primary cutaneous basal cell carcinoma. The Royal College of Pathologists. February 2019

Image sources


Actinic keratosis

Authors: Mikael Häggström; Authors of integrated Creative Commons article[1] [note 1]
Actinic keratosis may present as suspected malignant skin excisions.

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Gross processing

Multiple lesions of actinic keratosis on the scalp.

Gross examination

Note:

  • Color
  • Well-defined or diffuse border
  • Size
  • Any elevation

Lesions of actinic keratosis are typically ill-marginated, erythematous, scaling, and rough papules or patches. These will typically be found in areas displaying other signs of solar damage, such as atrophy, uneven pigmentation, and telangiectasias.[1]

Tissue selection

Tissue selection from suspected malignant skin lesions, by lesion size:[2][note 2]
<4 mm 4 - 8 mm 9 - 15 mm
Tissue selection from skin excision with less than 4 mm suspected malignant lesion.png Tissue selection from skin excision with 4-8 mm suspected malignant lesion.png Tissue selection from skin excision with 9-15 mm suspected malignant lesion.png

In table above, each top image shows recommended lines for cutting out slices to be submitted for further processing. Bottom image shows which side of the slice that should be put to microtomy. Dashed lines here mean that either side could be used. Further information: Gross processing of skin excisions

Microscopic evaluation

  • Evaluation mainly consists of:

Characteristics

Normal skin (left) and actinic keratosis (right) with the defining characteristic of atypical basal keratinocytes that does not involve the full thickness of the epidermis.
1(a). Actinic keratosis at low magnification, showing discontinuous parakeratosis (as the dysplastic process spares adnexal structures, including sebaceous glands. This specimen also demonstrates dense dermal elastosis).[1]

By definition, actinic keratosis is confined to foci within the epidermis.[1]
it also generally has:[1]

  • Aggregates of atypical, pleomorphic keratinocytes which show nuclear atypia, dyskeratosis, and loss of polarity.
  • Hyperkeratosis and parakeratosis, the latter overlying the abnormal cells in the epidermis. Due to the sparing of segments of the epithelium overlying adnexal structures, a characteristic pattern of alternating orthokeratosis and parakeratosis, referred to as the “flag-sign,” can often be seen (Figure 1(a)).
  • Atypical keratinocytes will not span the full thickness of the epidermis (Figure 1(b)), although those in the basal cell layer will frequently extend into the granular and cornified layers. The exception to this criterion is the Bowenoid variant of actinic keratosis, which resembles cutaneous squamous-cell carcinoma in situ (Bowen's disease) but is less disordered with less nuclear atypia and crowding.
  • A more basophilic basal layer than normal, which is generally thought to be a consequence of the close crowding of atypical keratinocytes (Figure 1(b)).
  • Some cases will also show basal layer degeneration and the formation of Civatte bodies (Figure 1(c)), the result of a lichenoid infiltrate with irregular acanthosis. This can be distinguished from lichenoid dermatitis by the presence of keratinocyte atypia.
  • Dermoepidermal junction irregularities, with small round buds at the basal cell layer that will protrude slightly into the upper papillary dermis (Figure 1(d)).
  • There is almost always an associated solar elastosis in the dermis, and a lack thereof can often be sufficient to prompt reconsideration of the diagnosis.


Squamous cell-like skin proliferations: Differential diagnosis

Main differential diagnoses and their characteristics:[3]

Clinical clues

  • Biopsy from sun exposed area (including the face, neck, dorsal hands, and forearms, upper chest, back, and scalp).[1]
  • Generally middle-aged or older individuals.[1]

Further workup

Once a diagnosis of actinic keratosis is established, optionally characterize the degree of atypia into either mild, moderate or severe.

Actinic keratosis with moderate atypia, spanning approximately half of stratum spinosum.

Histopathology report

  • Objective findings
  • A diagnosis of actinic keratosis
  • Optionally: The degree of atypia.
  • Even absence of evidence of malignancy.

Example for the case in "Further workup":

Histopathology of actinic keratosis with moderate atypia.jpg
(Skin excision with squamous stratified epithelium with moderate) atypia in the basal epidermis (, with enlarged and dark cell nuclei as well as slightly disrupted cell arrangements.) No evidence of malignancy.
  See also: General notes on reporting

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. The excision example shows a superficial basal cell carcinoma.
  3. - Buschke–Löwenstein tumor is an alternative name for verrucous squamous cell carcinoma in the ano-genital region.
    - Carcinoma cuniculatum is a characteristic form of verrucous squamous cell carcinoma on the sole.
  4. Inverted follicular keratosis is generally thought to be a rare variant of seborrheic keratosis, but this position is not universally accepted.
    - Karadag, AyseSerap; Ozlu, Emin; Uzuncakmak, TugbaKevser; Akdeniz, Necmettin; Cobanoglu, Bengu; Oman, Berkant (2016). "Inverted follicular keratosis successfully treated with imiquimod ". Indian Dermatology Online Journal 7 (3): 177. doi:10.4103/2229-5178.182354. ISSN 2229-5178. 

Main page

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Initially largely copied from: Yanofsky, Valerie R.; Mercer, Stephen E.; Phelps, Robert G. (2011). "Histopathological Variants of Cutaneous Squamous Cell Carcinoma: A Review ". Journal of Skin Cancer 2011: 1–13. doi:10.1155/2011/210813. ISSN 2090-2905. 
    -"This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited."
  2. There are many variants for the processing of skin excisions. These examples use aspects from the following sources: ". Ochsner J 5 (2): 22–33. 2003. PMID 22826680. PMC: 3399331. Archived from the original. . 
    - With a "standard histologic examination" that, in addition to the lesion, only includes one section from each side along the longest diameter of the specimen.
    - It also shows an example of circular coverage, with equal coverage distance in all four directions.
    - The entire specimen may be submitted if the risk of malignancy is high.
  3. Initially copied from: Paolino, Giovanni; Donati, Michele; Didona, Dario; Mercuri, Santo; Cantisani, Carmen (2017). "Histology of Non-Melanoma Skin Cancers: An Update ". Biomedicines 5 (4): 71. doi:10.3390/biomedicines5040071. ISSN 2227-9059. 
    "This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)."

Image sources


Squamous-cell carcinoma of the skin

Authors: Mikael Häggström; Authors of integrated Creative Commons article[1] [note 1]
Squamous-cell carcinoma (SCC) of the skin may present as suspected malignant skin excisions.

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Gross processing

Squamous cell carcinoma in situ.
SCC with scaling and ulceration.

If re-excision, see separate section at bottom.

Gross examination

Note:

  • Color
  • Well-defined or diffuse border
  • Size
  • Any elevation

Squamous cell carcinoma in situ (essentially synonymous with Bowen’s disease) often presents as an erythematous, well-demarcated, scaly patch or plaque, with a fairly irregular border. They occasionally present as dark skin focalities, especially when found in the genital region and the nails.[1]

Invasive SCC typically has ill-marginated, erythematous, scaling, and rough papules or patches.[1]

Tissue selection

Tissue selection from suspected malignant skin lesions, by lesion size:[2][note 2]
<4 mm 4 - 8 mm 9 - 15 mm
Tissue selection from skin excision with less than 4 mm suspected malignant lesion.png Tissue selection from skin excision with 4-8 mm suspected malignant lesion.png Tissue selection from skin excision with 9-15 mm suspected malignant lesion.png

In table above, each top image shows recommended lines for cutting out slices to be submitted for further processing. Bottom image shows which side of the slice that should be put to microtomy. Dashed lines here mean that either side could be used. Further information: Gross processing of skin excisions

Microscopic evaluation

Evaluation consists of:

  • Determining whether it is a SCC rather than a differential diagnosis.
  • Distinguishing a SCC in situ from an invasive SCC
  • Radicality, and if radical, determine the least distance to a margin.

Characteristics

Squamous cell carcinoma in situ, showing prominent dyskeratosis and aberrant mitoses at all levels of the epidermis, along with marked parakeratosis.[1]
Main characteristics of squamous-cell carcinoma regardless of location.
  • Malignant keratinocytes demonstrating intense mitotic activity, pleomorphism, and greatly enlarged nuclei. They will also show a loss of maturity and polarity, giving the epidermis a disordered or “windblown” appearance.

In situ

In SCC in situ (Bowen’s disease) the epidermis will show:

  • Atypia spanning the full thickness of the epidermis, being the main finding.[1]
  • Hyperkeratosis and parakeratosis.[1]
  • Marked acanthosis with elongation and thickening of the rete ridges. These changes will overly keratinocytic cells which are often highly atypical and may in fact have a more unusual appearance than invasive SCC.
  • Typical squamous-cell carcinoma cells are large with abundant eosinophilic cytoplasm and large, often vesicular, nuclei.[3]
  • Two types of multinucleated cells may be seen:[1]
  • Multinucleated giant cells
  • Dyskeratotic cells engulfed in the cytoplasm of keratinocytes.
  • Occasionally, cells of the upper epidermis will undergo vacuolization.[1]

There may be a mild to moderate lymphohistiocytic infiltrate detected in the upper dermis.[1]

Histopathology of squamous cell carcinoma in situ.jpg
Atypia spanning the full thickness of the epidermis is enough in this case for the diagnosis of SCC in situ. There is also a lymphohistiocytic infiltrate.

In contrast to actinic keratosis, the basal epidermal layer in SCC in situ is frequently spared, and will show little to no visible atypia. Additionally, SCC in situ will almost always involve both the interfollicular and adjacent follicular epithelium and adnexal structures.[1]

Overlap of squamous-cell and basal-cell carcinoma

Basal-cell carcinoma is generally distinguishable by for example relatively less cytoplasm, palisading, cleft formations and absence of horn cyst formation.

edit

Yet, a high prevalence means a relatively high incidence of borderline cases. In such cases, look particularly at the surface and attempt to classify as either of the following:

In unclear cases, the most useful immunohistochemistry marker appears to be MOC-31, which essentially always stains metatypical basal-cell carcinomas but not basaloid squamous-cell carcinomas.[5] UEA-1 appears to be the second most useful marker, staining almost all basaloid squamous-cell carcinomas but only a few metatypical basal-cell carcinomas.[5]

Clinical clues

  • Biopsy from sun exposed area (including the face, neck, dorsal hands, and forearms, upper chest, back, and scalp).[1]
  • Generally middle-aged or older individuals.[1]

In situ versus invasive

In situ (Bowen's disease)
Intact basement membrane.
Invasive SCC

Invasive SCC is defined by dermal infiltration.

This infiltrate can be somewhat difficult to detect in the early stages of invasion: however, additional indicators such as full thickness epidermal atypia and the involvement of hair follicles can be used to facilitate the diagnosis. Later stages of invasion are characterized by the formation of nests of atypical tumor cells in the dermis, often with a corresponding inflammatory infiltrate.[1]

Radicality

Determine whether the distances between atypical cells are more or less than 1 mm from the deep and radial edges. If less than 1 mm, quantify the distance.[6]

Degree of differentiation

This is applicable to invasive SCC. edit

Perineural or vascular invasion

In SCC, look for any perineural invasion,[note 3] and at least a quick glance for any vascular invasion.

Perineural invasion is defined as tumor in close proximity to nerve and involving at least 33% of its circumference or tumor cells within any of the three layers of the nerve sheath (epineurium, perineurium and endoneurium).[7] First look along the border of the tumor, followed by surrounding tissue, and if still not found, look through the rest of the tumor area as well.[1]

Staging

The AJCC, 8th Ed., does not include any staging system for skin SCC, except for tumors of the vulva.[8]

Optionally: Grading

Multiple variables can be combined to classify a SCC as low or high grade:

Low-Grade SCC[1] High-Grade SCC[1]
  • Well to moderately differentiated: intercellular bridges and keratin pearls
  • Tumor cells arranged in solid or sheet-like patterns
  • Association with solar damage and precursor actinic keratosis
  • Diameter less than 2 cm
  • Depth less than 2 mm
  • Poorly differentiated: clear-cell, sarcomatoid, or single cell features
  • Presence of infiltrating individual tumor cells
  • Arising de novo or in site of prior injury (ulcer, burn scar, or osteomyleitis)
  • Perineural and/or perivascular invasion
  • Diameter greater than 2 cm
  • Depth greater than 2 mm

Further work-up

In vulvar squamous cell carcinoma, generally perform p16 immunohistochemistry, which is considered a surrogate marker for oncogenic HPV infection.[9]

Microscopy report

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Components of the report:

  • Diagnosis of squamous-cell carcinoma
  • Whether it is in situ or invasive. If invasive:
  • Degree of differentiation.
  • (High or low grade.)
  • Even absence of perineural invasion[note 3]
  • ((Even absence of or vascular invasion.))
  • Radicality, mainly into either of the following: edit
  • >1 mm (as per Radicality above): "Clear margins" (or: "Clear margins at over __ mm")((or the exact distance thereof)).))
  • <1 mm but not continuous with edge: "Close margins at __ mm at (location). [[Locations are mainly the deep edge, or the (superior/inferior/medial/lateral) radial edge.]]."[6] Numbers are generally given at an exactness of 0.1 mm.
  • Continuous with margin: "Not radically excised at (location)."
  • Staging is only applicable for the head and neck (lip, ear, face, scalp and neck - see staging at Medscape) and vulva (see staging at cancer.net).

((You may also add a synoptic report (see examples):))

Examples

Squamous cell carcinoma in situ:

Micrograph of squamous cell carcinoma in situ - 100x.jpg
((Skin excision with squamous epithelium with))(central parakeratosis. The epidermis is thickened and exhibits disturbed stratification. )All cell layers show atypical epithelial cells with polymorphic and partially hyperchromatic nuclei. The basement membrane is intact. Clear margins. ((There is elastosis and inflammatory cells in the dermis.))

Invasive squamous cell carcinoma:

(Skin, right breast, excision:)
Invasive keratinizing squamous cell carcinoma, well differentiated, measuring 1.7 cm in greatest dimension.
Surgical margins are negative for carcinoma.
(Negative for lymphovascular and perineural invasion.)
((Solar elastosis.))

((Example synoptic report:))

  • Procedure: Skin excision.
  • Tumor site: Scalp
  • Tumor laterality: Right
  • Tumor focality: Unifocal
  • Tumor size: 1.6 x 1.4 cm
  • Tumor depth of invasion: 0.3 cm
  • Histologic type: Squamous cell carcinoma
  • Histologic grade: Moderately differentiated
  • Specimen margins: Uninvolved by invasive tumor.
  • Lymphovascular invasion: Not identified
  • Perineural invasion: Not identified
  • Regional lymph nodes: No lymph nodes submitted or found.
  • Pathologic Stage Classification (pTNM, AJCC 8th Edition):
  • Primary Tumor: pT1
  • Regional Lymph Nodes: pNX: Regional lymph nodes cannot be assessed
  • Additional pathologic findings: Actinic keratosis

Example microscopic description of invasive squamous cell carcinoma:

  • Squamous epithelium, with central ulceration, surrounded by hyperkeratosis. In this area in the dermis there are infiltrative nests of epithelioid cells with nuclear pleomorphism and <sparse / moderate / abundant> keratin formation.
  See also: General notes on reporting

Re-excisions

Gross processing

Tissue selection from skin re-excisions.png

edit
((Submit the entire specimen, or)) depending on radicality of previous excision:

  • Previously radical (including thin margins): Submit at least one central section across the surgical scar.[10]
  • Previously non-radical:
  • Visible lesion: Submit the entire scar.[10]
  • Lesion not visible: At least one additional radicality slice towards the tips, up to the entire specimen.[11]

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. The excision example shows a superficial basal cell carcinoma.
  3. 3.0 3.1 Presence or absence of perineural invasion in squamous-cell carcinoma affects whether adjuvant radiotherapy will be used.

Main page

References

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 1.23 Yanofsky, Valerie R.; Mercer, Stephen E.; Phelps, Robert G. (2011). "Histopathological Variants of Cutaneous Squamous Cell Carcinoma: A Review ". Journal of Skin Cancer 2011: 1–13. doi:10.1155/2011/210813. ISSN 2090-2905. .
    -"This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited."
  2. There are many variants for the processing of skin excisions. These examples use aspects from the following sources: ". Ochsner J 5 (2): 22–33. 2003. PMID 22826680. PMC: 3399331. Archived from the original. . 
    - With a "standard histologic examination" that, in addition to the lesion, only includes one section from each side along the longest diameter of the specimen.
    - It also shows an example of circular coverage, with equal coverage distance in all four directions.
    - The entire specimen may be submitted if the risk of malignancy is high.
  3. Dr Nicholas Turnbull, A/Prof Patrick Emanual (2014-05-03). Squamous cell carcinoma pathology. DermNetz.
  4. El-Mofty, SK. (2014). "Histopathologic risk factors in oral and oropharyngeal squamous cell carcinoma variants: An update with special reference to HPV-related carcinomas ". Medicina Oral Patología Oral y Cirugia Bucal: e377–e385. doi:10.4317/medoral.20184. ISSN 16986946. 
    License: CC BY 2.5
  5. 5.0 5.1 Webb, David V.; Mentrikoski, Mark J.; Verduin, Lindsey; Brill, Louis B.; Wick, Mark R. (2015). "Basal cell carcinoma vs basaloid squamous cell carcinoma of the skin: an immunohistochemical reappraisal ". Annals of Diagnostic Pathology 19 (2): 70–75. doi:10.1016/j.anndiagpath.2015.01.004. ISSN 10929134. 
  6. 6.0 6.1 1 mm as cutoff for close margin: Brodie M Elliott, Benjamin R Douglass, Daniel McConnell, Blair Johnson, Christopher Harmston (2018-12-14). New Zealand Medical Journal.
  7. Strowd, Roy (2021). Neuro-oncology for the clinical neurologist . Philadelphia, PA: Elsevier. ISBN 978-0-323-69494-0. OCLC 1220993756. 
  8. Amin, Mahul (2017). AJCC cancer staging manual (8 ed.). Switzerland: Springer. ISBN 978-3-319-40617-6. OCLC 961218414. 
    - For access, see the Secrets chapter of Patholines.
    - Copyright note: The AJCC, 8th Ed. is published by a company in Switzerland, and the tables presented therein are Public Domain because they consist of tabular information without literary or artistic innovation, and therefore do not fulfil the inclusion criterion of the Swiss Copyright Act (CopA) which applies to "literary and artistic intellectual creations with individual character" (see Federal Act on Copyright and Related Rights (Copyright Act, CopA) of 9 October 1992 (Status as of 1 January 2022)). edit
  9. Anjelica Hodgson, M.D., Carlos Parra-Herran, M.D.. p16. Pathology Outlines. Last author update: 1 July 2017. Last staff update: 20 July 2022
  10. 10.0 10.1 Katarzyna Lundmark. Handläggning av hudprover – provtagningsanvisningar, utskärningsprinciper och snittning (Handling of skin samples - sampling instructions, cutting principles and incision. Swedish Society of Pathology.
  11. Pathology Department at NU Hospital Group, Sweden, 2019-2020.

Image sources


Melanoma in situ

Author: Mikael Häggström [note 1]
Melanoma of the skin generally presents as a dark skin focality and/or a suspected malignant skin excision.

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Gross processing

Gross examination

Note:

  • Color
  • Well-defined or diffuse border
  • Size
  • Any elevation

Tissue selection

Tissue selection from suspected malignant skin lesions, by lesion size:[1][note 2]
<4 mm 4 - 8 mm 9 - 15 mm
Tissue selection from skin excision with less than 4 mm suspected malignant lesion.png Tissue selection from skin excision with 4-8 mm suspected malignant lesion.png Tissue selection from skin excision with 9-15 mm suspected malignant lesion.png

In table above, each top image shows recommended lines for cutting out slices to be submitted for further processing. Bottom image shows which side of the slice that should be put to microtomy. Dashed lines here mean that either side could be used. Further information: Gross processing of skin excisions

Microscopic evaluation

Differential diagnoses

Distinguish mainly from dysplastic nevus and invasive melanoma of the skin:

Dysplastic nevus

Comparison of congenital pattern nevus, dysplastic nevus and suspected melanoma   edit
Parameter Non-atypical congenital pattern Low-grade dysplastic nevus High-grade dysplastic nevus Suspected melanoma in situ
Mild dysplasia Moderate dysplasia Severe dysplasia
Macroscopic Lateral circumscription[2] Sharp Slightly diminished Moderate Poor
Excised melanoma in situ.jpg
Symmetry[2] Good Often broken Rare
Structural
(Low
mag.)
Delimitation[3] Rarely diffuse Sometimes diffuse Often diffuse
Lentiginous proliferation[note 3][3] Yes, along with rete pegs Yes, along with and focally between rete pegs Yes, along with and focally between rete pegs Yes partially continuous, multilayered
Histopathology of lentigo maligna.jpg
Bridging[3] Rarely Often
Confluent nests[3] Rarely Sometimes Often Often widespread
Pigment distribution[3] Regular Irregular
Suprabasal presence (less than most superficial third of subcorneal epidermis) Occasionally centrally[2] No[3] or rarely[2] Occasionally centrally[2] Yes, multifocal[3]
Pagetoid migration including superficial third of subcorneal epidermis[3] No No Yes, in a maximum of 2 HPF centrally, but not peripherally Yes, multifocal and/or in periphery
Peripheral.
Extended rete pegs Ocassional[2] Yes, regular[3] Yes, varying[3] Yes, often irregular[3] Varying, flattened[3]
Concentric fibrosis Regressive[2] Yes[3] Occasional[2]
Lamellar fibrosis Rarely[3] Often[3] Often pronounced[3] Occasional[2]
Lymphocytic infiltrate[3] Mild, perivascular Mild or moderate, perivascular Varying Varying
Suprapapillary plate involvement No[2] Usually no[2] Often[2] Yes[2]
Cellular
(high
mag.)
Image Compound nevus with moderate atypia.jpg
Junctional extension[2] Unusual Usual Extensive
Nuclear size[2] Age-related Small Medium Large Medium or large. Pleomorphic[4]
Nuclear pleomorphism[5] Slight Prominent
Chromatin pattern Uniform[2] Condensed[2] Partically expanded[2] Expanded, coarse in some cells[2] Expanded, hyperchromatic, coarse.[2] Usually granular.[5]
Nucleoli[2] Age-related Small Medium Large Usually[5] large
Mitoses[2] Few superficial Superficial and deep
Histological regression[5][note 4] Usually Usually not
Percentage of atypical melanocytes[3] <10% About 10 - 50% about 50-90% Usually> 90%
Intradermal melanocytic atypia[3] No Rarely, in superficial part Can be detected in superficial part
Intradermal melanocyte maturation[3] Yes Yes, can be partial Yes, can be partial Variable

In suspected but not certain nevus or melanoma in situ, generally perform immunohistochemistry with SOX10, whereby melanocyte proliferation and nuclear pleomorphism is easier to see.[note 5]

Further information: Evaluation of suspected malignancies

Invasive melanoma of the skin

Invasive melanoma of the skin has features melanoma in situ, but also has dermal involvement of atypical melanocytes with cytologic atypia and no maturation.[6]

Further workup

Upon a diagnosis of melanoma in situ, evaluate its margins.
Optionally, attempt to determine the histopathologic type and amount of cytoplasmic pigmentation:

Margins

If melanoma, determine if the distance to any margin is greater or lesser than 2-3 mm.

  • 2 mm is used as a cutoff for sharply demarcated, small, superficially spreading or nevoid melanomas.[7]
  • 3 mm is used for ill-defined lentigo maligna melanoma in situ.[7]

If lesser, quantify the distance.

If margins are difficult to determine, consider immunohistochemistry with SOX10 to better visualize melanoma nests.[note 5]

Histopathologic type

Main types of melanoma in situ are:

Type Features Micrograph
Superficial spreading melanoma in situ Melanoma cells with nest formation along the dermo-epidermal junction. Histopathology of superficial spreading melanoma.jpg
Lentigo maligna Linear spread of atypical epidermal melanocytes along stratum basale.[8]
Histopathology of lentigo maligna.jpg
Acral lentiginous melanoma in situ Continuous proliferation of atypical melanocytes at the dermoepidermal junction.[9] Histopathology of acral lentiginous melanoma in situ, intermediate magnification.jpg

Report

Most important entries:

  • Melanoma area dimensions (width x width)[10]
  • Radicality,[10] mainly into either of the following: edit
  • >2 or 3 mm (as per Further workup above): "Clear margins" (or: "Clear margins at over __ mm")((or the exact distance thereof)).))
  • <2 or 3 mm but not continuous with edge: "Close margins at __ mm at (location). [[Locations are mainly the deep edge, or the (superior/inferior/medial/lateral) radial edge.]]." Numbers are generally given at an exactness of 0.1 mm.
  • Continuous with margin: "Not radically excised at (location)."
  See also: General notes on reporting

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. The excision example shows a superficial basal cell carcinoma.
  3. Lentiginous proliferation is proliferation along the basal layer of the epidermis
  4. Histological regression is one or more areas within a tumor in which neoplastic cells have disappeared or decreased in number. In this case, this means complete or partial disappearance from areas of the dermis (and occasionally from the epidermis), which have been replaced by fibrosis, accompanied by melanophages, new blood vessels, and a variable degree of inflammation.
    - Ribero, Simone; Gualano, Maria Rosaria; Osella-Abate, Simona; Scaioli, Giacomo; Bert, Fabrizio; Sanlorenzo, Martina; Balagna, Elena; Fierro, Maria Teresa; et al. (2015). "Association of Histologic Regression in Primary Melanoma With Sentinel Lymph Node Status ". JAMA Dermatology 151 (12): 1301. doi:10.1001/jamadermatol.2015.2235. ISSN 2168-6068. 
  5. 5.0 5.1 SOX10 stains cell nuclei of melanocytes.
    - Miettinen, Markku; McCue, Peter A.; Sarlomo-Rikala, Maarit; Biernat, Wojciech; Czapiewski, Piotr; Kopczynski, Janusz; Thompson, Lester D.; Lasota, Jerzy; et al. (2015). "Sox10—A Marker for Not Only Schwannian and Melanocytic Neoplasms But Also Myoepithelial Cell Tumors of Soft Tissue ". The American Journal of Surgical Pathology 39 (6): 826–835. doi:10.1097/PAS.0000000000000398. ISSN 0147-5185. 

Main page

References

  1. There are many variants for the processing of skin excisions. These examples use aspects from the following sources: ". Ochsner J 5 (2): 22–33. 2003. PMID 22826680. PMC: 3399331. Archived from the original. . 
    - With a "standard histologic examination" that, in addition to the lesion, only includes one section from each side along the longest diameter of the specimen.
    - It also shows an example of circular coverage, with equal coverage distance in all four directions.
    - The entire specimen may be submitted if the risk of malignancy is high.
  2. 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 2.14 2.15 2.16 2.17 2.18 2.19 2.20 2.21 Arumi-Uria, Montserrat; McNutt, N Scott; Finnerty, Bridget (2003). "Grading of Atypia in Nevi: Correlation with Melanoma Risk ". Modern Pathology 16 (8): 764–771. doi:10.1097/01.MP.0000082394.91761.E5. ISSN 0893-3952. 
  3. 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 Katarzyna Lundmark, Britta Krynitz, Ismini Vassilaki, Lena Mölne, Annika Ternesten Bratel. Histopatologisk bedömning och gradering av dysplastiskt nevus samt gränsdragning mot melanom in situ/melanom (Histopathological assessment and grading of dysplastic nevus and distinction from melanoma in situ/melanoma). KVAST (Swedish Society of Pathology). Retrieved on 2019-09-18.
  4. Christopher S. Hale. Skin melanocytic tumor - Melanoma - Invasive melanoma. Topic Completed: 1 May 2013. Revised: 17 September 2019
  5. 5.0 5.1 5.2 5.3 Husain, Ehab A; Mein, Charles; Pozo, Lucia; Blanes, Alfredo; Diaz-Cano, Salvador J (2011). "Heterogeneous topographic profiles of kinetic and cell cycle regulator microsatellites in atypical (dysplastic) melanocytic nevi ". Modern Pathology 24 (4): 471–486. doi:10.1038/modpathol.2010.143. ISSN 0893-3952. 
  6. Christopher S. Hale. Skin melanocytic tumor - Melanoma - Invasive melanoma. Pathology Outlines. Topic Completed: 1 May 2013. Revised: 17 September 2019
  7. 7.0 7.1 Measurements used to classify a melanoma as radical: Page 406 in: Klaus J. Busam, Richard A Scolyer, Pedram Gerami (2018). Pathology of Melanocytic Tumors . Elsevier Health Sciences. ISBN 9780323508681. 
  8. Error on call to Template:cite web: Parameters url and title must be specifiedHon A/Prof Amanda Oakley (2011). . DermNet NZ.
  9. Piliang, Melissa Peck (2009). "Acral Lentiginous Melanoma ". Surgical Pathology Clinics 2 (3): 535–541. doi:10.1016/j.path.2009.08.005. ISSN 18759181. 
  10. 10.0 10.1 . An Example of a Melanoma Pathology Report. Melanoma Foundation. Retrieved on 2019-09-24.

Image sources


Invasive melanoma of the skin

Author: Mikael Häggström [note 1]
Melanoma of the skin generally presents as a dark skin focality.

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Gross processing

Gross examination

Note:

  • Color
  • Well-defined or diffuse border
  • Size
  • Any elevation

Tissue selection

Tissue selection from suspected malignant skin lesions, by lesion size:[1][note 2]
<4 mm 4 - 8 mm 9 - 15 mm
Tissue selection from skin excision with less than 4 mm suspected malignant lesion.png Tissue selection from skin excision with 4-8 mm suspected malignant lesion.png Tissue selection from skin excision with 9-15 mm suspected malignant lesion.png

In table above, each top image shows recommended lines for cutting out slices to be submitted for further processing. Bottom image shows which side of the slice that should be put to microtomy. Dashed lines here mean that either side could be used. Further information: Gross processing of skin excisions

Microscopic evaluation

Differential diagnoses

Dermal nevus

Comparison of dermal nevus and suspected invasive melanoma   edit
Parameter Non-dysplastic dermal nevus Low-grade dysplastic dermal nevus High-grade dysplastic dermal nevus Suspected invasive melanoma
Mild dysplasia Moderate dysplasia Severe dysplasia
Macroscopic Lateral circumscription[3] Sharp Slightly diminished Moderate Poor
Excised melanoma in situ.jpg
Symmetry[3] Good Often broken Rare
Structural
(Low
mag.)
Micrograph Histopathology of non-dysplastic dermal nevus, low magnification.jpg Histopathology of invasive acral lentiginous melanoma.jpg
Delimitation[4] Rarely diffuse Sometimes diffuse Often diffuse
Confluent nests[4] Rarely Sometimes Often Often widespread
Pigment distribution[4] Regular Irregular
Concentric fibrosis Regressive (see below table)[3] Yes[4] Occasional[3]
Lamellar fibrosis Rarely[4] Often[4] Often pronounced[4] Occasional[3]
Lymphocytic infiltrate[4] Mild, perivascular Mild or moderate, perivascular Varying Varying
Cellular
(high
mag.)
Micrographs Histopathology of dermal nevus, high magnification.jpg Histopathology of invasive melanoma, high magnification.jpg
Nuclear size[3] Small Medium Large Medium or large. Pleomorphic[5]
Nuclear pleomorphism[6] Slight superficial Slight Prominent
Chromatin pattern Uniform[3] Condensed[3] Partically expanded[3] Expanded, coarse in some cells[3] Expanded, hyperchromatic, coarse.[3] Usually granular.[6]
Nucleoli[3] Small Medium Large Usually[6] large
Mitoses[3] Few superficial Superficial and deep
Histological regression[6] (see below table) Usually Usually not
Percentage of atypical melanocytes[4] <10% About 10 - 50% about 50-90% Usually> 90%

Histological regression is one or more areas within a tumor in which neoplastic cells have disappeared or decreased in number. In this case, it means complete or partial disappearance of neoplastic cells from areas of the dermis (and occasionally from the epidermis), which have been replaced by fibrosis, accompanied by melanophages, new blood vessels, and a variable degree of inflammation.[7]

In suspected but not certain nevus or melanoma, generally perform immunohistochemistry with SOX10 (which stains cell nuclei of melanocytes), whereby melanocyte proliferation and nuclear pleomorphism is easier to see:[8]


Further workup

In case a diagnosis of invasive melanoma of the skin can be made, the following are generally mandatory:

  • Margins
  • Depth
  • Any ulceration
  • Histopathologic type.[9]
  • Presence of mitoses in the intradermal component.[9]

The following aspects are mandatory in some regions:

  • Clark's level (not mandatory in the US)[note 3]

Margins

Determine if the distance to any margin is greater or lesser than 3 mm.[10] If a margin is closer, measure it at an exactness of 0.1 mm.

If margins are difficult to determine, consider immunohistochemistry with SOX10 (staining the nuclei of melanocytes), to better visualize melanoma nests.[11]

Depth and ulceration

For invasive melanoma, measure the depth and whether there is ulceration or not, so as to be able to classify the T stage (following table by AJCC, 8th edition):[12]

T Category Thickness Ulceration status
TX: primary tumor
thickness cannot be
assessed (e.g., diagnosis
by curettage)
Not applicable Not applicable
T0: no evidence of
primary tumor (e.g.,
unknown primary or
completely regressed
melanoma)
Not applicable Not applicable
Tis (melanoma in situ) Not applicable Not applicable
T1 ≤1.0 mm Unknown or unspecified
T1a <0.8 mm Without ulceration
T1b <0.8 mm With ulceration
0.8–1.0 mm With or without ulceration
T2 >1.0–2.0 mm Unknown or unspecified
T2a >1.0–2.0 mm Without ulceration
T2b >1.0–2.0 mm With ulceration
T3 >2.0‐4.0 mm Unknown or unspecified
T3a >2.0–4.0 mm Without ulceration
T3b >2.0–4.0 mm With ulceration
T4 >4.0 mm Unknown or unspecified
T4a >4.0 mm Without ulceration
T4b >4.0 mm With ulceration

Histopathologic type

If needing to evaluate, the main types of invasive melanoma are:[13]

Type Features Relative incidence
(in comparison to all melanomas)[13]
Photograph Micrograph
Superficial spreading melanoma Melanoma cells with nest formation along the dermo-epidermal junction. 70% Superficial spreading melanoma in situ on dermoscopy.jpg Histopathology of superficial spreading melanoma.jpg
Nodular melanoma Grows relatively more in depth than in width. 15% - 20% Photography of nodular melanoma.jpg Histopathology of nodular melanoma.jpg
Lentigo maligna melanoma Atypical epidermal melanocytes as well as invasion into the dermis.[14] 5% - 10% Photograph of lentigo maligna melanoma.jpg Histopathology of lentigo maligna melanoma.jpg
Acral lentiginous melanoma Continuous proliferation of atypical melanocytes at the dermoepidermal junction.[15] 7% - 10% Photography of a large acral lentiginous melanoma.jpg Histopathology of invasive acral lentiginous melanoma.jpg

Clark's level

Skin layers.

If needing to evaluate,[note 3] Clark's levels are:[16]

  • Level 1: Melanoma confined to the epidermis (melanoma in situ)
  • Level 2: Invasion into the papillary dermis
  • Level 3: Invasion to the junction of the papillary and reticular dermis
  • Level 4: Invasion into the reticular dermis
  • Level 5: Invasion into subcutaneous tissue.

Tumor‐infiltrating Lymphocytes (TILs)

Classify as either of the following:[12]

  • Absent TIL infiltrate: no lymphocytes present or, if present, they do not interact with tumor cells.
  • Non-brisk TIL infiltrate: focal areas of lymphocytic infiltration in the tumor.
  • Brisk TIL infiltrate: TIL infiltration of the entire base of the tumor, or diffuse permeation of the tumor.

Lymph nodes

Cells that stain for melan-A but are nevus-like may be a capsular nevus

If negative on H&E stain, generally use immunohistochemistry for melanoma markers (such as a combination of melan-A and HMB-45) to exclude micrometastasis:

Other parameters

Optionally, the following parameters can be given:[17]

  • histological regression, with complete or partial disappearance from areas of the dermis (and occasionally from the epidermis), which have been replaced by fibrosis, accompanied by melanophages, new blood vessels, and a variable degree of inflammation.[18]
Further information: Evaluation of tumors

Report

Report when evaluated (as per mandatory vs. optional in Further workup above):

  • Melanoma area dimensions (width x width)[19]
  • Radicality,[19] mainly into either of the following: edit
  • >3 mm : "Clear margins" (or: "Clear margins at over __ mm")((or the exact distance thereof)).))
  • <3 mm but not continuous with edge: "Close margins at __ mm at (location). [[Locations are mainly the deep edge, or the (superior/inferior/medial/lateral) radial edge.]]." Numbers are generally given at an exactness of 0.1 mm.
  • Continuous with margin: "Not radically excised at (location)."
  • Depth or most distant invasion of melanoma cells.[19]
  • Ulceration or not, and maximum dimension if present
  • Stage as per AJCC
  • Clark's level
  • Histopathologic type
  • Mitotic rate, as amount per mm2
  • Significant signs of regression
  • Cytoplasmic pigmentation
  • Melanoma cell shapes

US example

Skin, mid upper back, excision:

  • Malignant melanoma, nodular type, Clark level IV, Breslow thickness 10mm. Surgical margins are negative for melanoma.

See synoptic report.

SYNOPTIC REPORT:

Specimen

Procedure:  Excision

Specimen Laterality:  Midline

Tumor

Tumor Site:  Skin of trunk

Histologic Type:  Nodular melanoma

Maximum Tumor (Breslow) Thickness (Millimeters): 10 mm

Macroscopic Satellite Nodule(s): Not identified

Ulceration: Present

Extent of Ulceration (Millimeters):  12 mm

Anatomic (Clark) Level: IV (Melanoma invades reticular dermis)

Mitotic Rate:  18 mitoses / mm2

Microsatellite(s):  Not identified

Lymphovascular Invasion:  Not identified

Neurotropism:  Not identified

Tumor-Infiltrating Lymphocytes:  Present, nonbrisk

Tumor Regression:  Not identified

Margins

Peripheral Margins:  Negative for invasive melanoma

Distance of Invasive Melanoma from Closest Peripheral Margin (Millimeters):  5 mm

Location:  3 o'clock and 9 o'clock

Status of melanoma in situ at peripheral margins: Negative for melanoma in situ

Distance of melanoma in situ from closest peripheral margin (millimeters):  Cannot be determined - Ulcerated surface and no in-situ noted in the remaining surface

Location:  Lateral

Deep Margin:  Negative for invasive melanoma

Distance of Invasive Melanoma from Deep Margin (Millimeters):  2 mm

Status of Melanoma in situ at Deep Margin: Negative for melanoma in situ

Distance of Melanoma in situ from Deep Margin (Millimeters):  Cannot be determined (negative for melanoma in situ)

Lymph Nodes

Regional Lymph Nodes:  No lymph nodes submitted or found

Pathologic Stage Classification (pTNM, AJCC 8th Edition)

Primary Tumor (pT):  pT4b

Regional Lymph Nodes (pN):  pNX

European example

Sun-damaged skin with central diffusely delimited proliferation of melanocytic cells having polymorphic cell nuclei, distinct nucleoli and uneven light brown pigmentation. An area of pagetoid migration is seen. There is ulceration of a smaller area. The radial margin is over 3.0 mm and the deep margin is 2.0 mm.

  • Free margin: Yes
  • Margin in mm: 2.0 mm
  • Tumor depth: 1.2 mm
  • Ulceration: Yes
  • Stage: T2b
  • Clark's level: IV
  • Histopathologic type: Superficial spreading melanoma
  • Presence of mitoses: Yes
  • Significant signs of regression: No
  See also: General notes on reporting

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. The excision example shows a superficial basal cell carcinoma.
  3. 3.0 3.1 Clark's level is not included in United States AJCC guidelines, but is mandatory for melanomas in Sweden.
    -. Breslow Depth and Clark Level. Melanoma Research Alliance. Retrieved on 2020-02-13.
    - . Bilaga 6. Kvalitetsbilaga för patologi (KVAST-bilaga). Regionala Cancercentrum i Samverkan, guidelines by Swedish Society of Pathology. Retrieved on 2020-02-13.

Main page

References

  1. There are many variants for the processing of skin excisions. These examples use aspects from the following sources: ". Ochsner J 5 (2): 22–33. 2003. PMID 22826680. PMC: 3399331. Archived from the original. . 
    - With a "standard histologic examination" that, in addition to the lesion, only includes one section from each side along the longest diameter of the specimen.
    - It also shows an example of circular coverage, with equal coverage distance in all four directions.
    - The entire specimen may be submitted if the risk of malignancy is high.
  2. . Melanoma in situ (stage 0). Cancer Research UK. Last reviewed: 27 Jun 2019
  3. 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 Arumi-Uria, Montserrat; McNutt, N Scott; Finnerty, Bridget (2003). "Grading of Atypia in Nevi: Correlation with Melanoma Risk ". Modern Pathology 16 (8): 764–771. doi:10.1097/01.MP.0000082394.91761.E5. ISSN 0893-3952. 
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 Katarzyna Lundmark, Britta Krynitz, Ismini Vassilaki, Lena Mölne, Annika Ternesten Bratel. Histopatologisk bedömning och gradering av dysplastiskt nevus samt gränsdragning mot melanom in situ/melanom (Histopathological assessment and grading of dysplastic nevus and distinction from melanoma in situ/melanoma). KVAST (Swedish Society of Pathology). Retrieved on 2019-09-18.
  5. Christopher S. Hale. Skin melanocytic tumor - Melanoma - Invasive melanoma. Topic Completed: 1 May 2013. Revised: 17 September 2019
  6. 6.0 6.1 6.2 6.3 Husain, Ehab A; Mein, Charles; Pozo, Lucia; Blanes, Alfredo; Diaz-Cano, Salvador J (2011). "Heterogeneous topographic profiles of kinetic and cell cycle regulator microsatellites in atypical (dysplastic) melanocytic nevi ". Modern Pathology 24 (4): 471–486. doi:10.1038/modpathol.2010.143. ISSN 0893-3952. 
  7. Ribero, Simone; Gualano, Maria Rosaria; Osella-Abate, Simona; Scaioli, Giacomo; Bert, Fabrizio; Sanlorenzo, Martina; Balagna, Elena; Fierro, Maria Teresa; et al. (2015). "Association of Histologic Regression in Primary Melanoma With Sentinel Lymph Node Status ". JAMA Dermatology 151 (12): 1301. doi:10.1001/jamadermatol.2015.2235. ISSN 2168-6068. 
  8. Miettinen, Markku; McCue, Peter A.; Sarlomo-Rikala, Maarit; Biernat, Wojciech; Czapiewski, Piotr; Kopczynski, Janusz; Thompson, Lester D.; Lasota, Jerzy; et al. (2015). "Sox10—A Marker for Not Only Schwannian and Melanocytic Neoplasms But Also Myoepithelial Cell Tumors of Soft Tissue ". The American Journal of Surgical Pathology 39 (6): 826–835. doi:10.1097/PAS.0000000000000398. ISSN 0147-5185. 
  9. 9.0 9.1 - USA: . [https://documents.cap.org/protocols/Skin.Melanoma_4.3.0.2.REL_CAPCP.pdf Protocol for the Examination of Excision Specimens From Patients With Melanoma of the Skin]. COllege of American Pathologists. Version: 4.3.0.2. Protocol Posting Date: November 2021
    -Sweden: . Bilaga 6. Kvalitetsbilaga för patologi (KVAST-bilaga). Regionala Cancercentrum i Samverkan, guidelines by Swedish Society of Pathology. Retrieved on 2020-02-13.
  10. Definition of "thin margin": Wolf, Y.; Balicer, R.D.; Amir, A.; Feinmesser, M.; Hauben, D.J. (2001). "The vertical dimension in the surgical treatment of cutaneous malignant melanoma – how deep is deep? ". European Journal of Plastic Surgery 24 (2): 74–77. doi:10.1007/s002380100225. ISSN 0930-343X. 
  11. Miettinen, Markku; McCue, Peter A.; Sarlomo-Rikala, Maarit; Biernat, Wojciech; Czapiewski, Piotr; Kopczynski, Janusz; Thompson, Lester D.; Lasota, Jerzy; et al. (2015). "Sox10—A Marker for Not Only Schwannian and Melanocytic Neoplasms But Also Myoepithelial Cell Tumors of Soft Tissue ". The American Journal of Surgical Pathology 39 (6): 826–835. doi:10.1097/PAS.0000000000000398. ISSN 0147-5185. 
  12. 12.0 12.1 Amin, Mahul (2017). AJCC cancer staging manual (8 ed.). Switzerland: Springer. ISBN 978-3-319-40617-6. OCLC 961218414. 
    - For access, see the Secrets chapter of Patholines.
    - Copyright note: The AJCC, 8th Ed. is published by a company in Switzerland, and the tables presented therein are Public Domain because they consist of tabular information without literary or artistic innovation, and therefore do not fulfil the inclusion criterion of the Swiss Copyright Act (CopA) which applies to "literary and artistic intellectual creations with individual character" (see Federal Act on Copyright and Related Rights (Copyright Act, CopA) of 9 October 1992 (Status as of 1 January 2022)). edit
  13. 13.0 13.1 [https://books.google.se/books?id=wGclDwAAQBAJ&pg=PA805 Page 805 in: Ferri, Fred (2019). Ferri's clinical advisor 2019 : 5 books in 1 . Philadelphia, PA: Elsevier. ISBN 978-0-323-52957-0. OCLC 1040695302. 
  14. Michael Xiong; Ahmad Charifa; Chih Shan J. Chen.. Cancer, Lentigo Maligna Melanoma. StatPearls, National Center for Biotechnology Information. Last Update: May 18, 2019.
  15. Piliang, Melissa Peck (2009). "Acral Lentiginous Melanoma ". Surgical Pathology Clinics 2 (3): 535–541. doi:10.1016/j.path.2009.08.005. ISSN 18759181. 
  16. . NCI Dictionary of Cancer Terms. National Cancer Institute. Retrieved on 2020-02-13.
  17. Rees, Jonathan; Viros, Amaya; Fridlyand, Jane; Bauer, Juergen; Lasithiotakis, Konstantin; Garbe, Claus; Pinkel, Daniel; Bastian, Boris C (2008). "Improving Melanoma Classification by Integrating Genetic and Morphologic Features ". PLoS Medicine 5 (6): e120. doi:10.1371/journal.pmed.0050120. ISSN 1549-1676. 
  18. Ribero, Simone; Gualano, Maria Rosaria; Osella-Abate, Simona; Scaioli, Giacomo; Bert, Fabrizio; Sanlorenzo, Martina; Balagna, Elena; Fierro, Maria Teresa; et al. (2015). "Association of Histologic Regression in Primary Melanoma With Sentinel Lymph Node Status ". JAMA Dermatology 151 (12): 1301. doi:10.1001/jamadermatol.2015.2235. ISSN 2168-6068. 
  19. 19.0 19.1 19.2 . An Example of a Melanoma Pathology Report. Melanoma Foundation. Retrieved on 2019-09-24.

Image sources


Dermatitis

Author: Mikael Häggström [note 1]
Scope: This article deals with skin conditions where inflammation is the main finding, excluding suspected malignant skin excisions (where inflammation is often a concurrent finding).

Sampling

  • For punch biopsies, a size of 4 mm is preferred for most inflammatory dermatoses.[1]
  • Panniculitis or cutaneous lymphoproliferative disorders: 6 mm punch biopsy or skin excision.[1]

A superficial or shave biopsy is regarded as insufficient.[1]

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Gross processing

Gross pathology processing of skin lesions with benign appearance, by lesion size:[4]
<4 mm 4 - 8 mm 9 - 15 mm

Tissue selection from skin excision with lesion less than 4 mm with benign appearance.png

Tissue selection from skin excision with lesion 4-8 mm with benign appearance.png

Tissue selection from skin excision with lesion 9-15 mm with benign appearance.png

In table above, each top image shows recommended lines for cutting out slices to be submitted for further processing. Bottom image shows which side of the slice that should be put to microtomy. Dashed lines here mean that either side could be used. Further information: Gross processing of skin excisions

Staining

3 H&E sections and one section with periodic acid Schiff (PAS)[note 2][1]

  • If suspected bacterial and fungal microorganisms, consider Gram stain and Gomori methenamine silver stain.[1]

Microscopic evaluation

One approach is to classify into mainly either of the following, primarily based on depth of involvement:[1]

  • Epidermis, papillary dermis, and superficial vascular plexus:
  • Vesiculobullous lesions
  • Pustular dermatosis
  • Non vesicullobullous, non-pustular
  • With epidermal changes
  • Without epidermal changes. These characteristically have a superficial perivascular inflammatory infiltrate, and can be classified by type of cell infiltrate:[1]
  • Lymphocytic (most common)
  • Lymphoeosinophilic
  • Lymphoplasmacytic
  • Mast cell
  • Lymphohistiocytic
  • Neutrophilic
  • No visible pathology

Continue in corresponding section:

Non vesicullobullous, non-pustular lesions with epidermal changes

Spongiotic dermatitis

It is characterized by epithelial intercellular edema.[1]

Characteristics Micrograph Photograph
Acute Subacute Chronic
Generally/Not otherwise specified[note 3] Typical findings:[1]
  • Variable degree of epidermal spongiosis and vesicle formation, filled with proteinaceous fluid containing lymphocytes and histiocytes.
  • Usually superficial dermal edema with perivascular lymphocytic infiltrate, with exocytosis.
  • No acanthosis or parakeratosis.
Typical findings:[1]
  • Mild to moderate spongiosis and exocytosis of inflammatory cells
  • Irregular acanthosis and parakeratosis.
  • Superficial dermal perivascular lymphohistiocytic infiltrate
  • Swelling of endothelial cells
  • Papillary dermal edema are present
Typical findings:[1]
  • The spongiosis is mild to absent
  • Pronounced irregular acanthosis, hyperkeratosis, and parakeratosis
  • Minimal dermal inflammation and exocytosis of inflammatory cells are present.
  • Possibly fibrosis of papillary dermis

PAS stain is essential to exclude fungal infection.[1]

Micrograph of subacute spongiotic dermatitis.jpg Subacute
Allergic/contact dermatitis or atopic dermatitis As above. Eosinophils may be present in the dermis and epidermis (eosinophilic spongiosis).[1] Spongiotic dermatitis from drug allergy.jpg Allergic dermatitis Eczema (14100950936).jpg Atopic dermatitis
Seborrheic dermatitis Typical findings:[5]
  • Focal, usually mild, spongiosis with overlying scale crust, with a few neutrophils
  • The crust is often centered on a follicle
  • The papillary dermis is generally mildly edematous
  • Dilated blood vessels in the superficial vascular plexus
  • Mild superficial perivascular infiltrate of lymphocytes, histiocytes and occasional neutrophils. There is some exocytosis of inflammatory cells but not as prominent as in nummular dermatitis
Typical findings:[5]
  • Psoriasiform hyperplasia, initially slight, with mild spongiosis
  • Usually numerous yeast-like organisms in the surface keratin
  • Same changes as seen in acute stage.
Typical findings:[5]
  • More pronounced psoriasiform hyperplasia
  • Only minimal spongiosis
  • Presence of scaling crusts in a folliculocentric distribution, distinguishes from psoriasis.
Seborrhoeic dermatitis example.jpg

In addition to above, an unspecific spongiotic dermatitis can be consistent with nummular dermatitis, dyshidrotic dermatitis, Id reaction, dermatophytosis, miliaria, Gianotti-Crosti syndrome and pityriasis rosea.[1][note 3]

Interface dermatitis

These are sorted into either:[1]

  • Interface dermatitis with vacuolar change
  • Interface dermatitis with lichenoid inflammation
Interface dermatitis with vacuolar change
Causes of vacuolar interface dermatitis edit
Main conditions[6] Characteristics Micrograph Photograph
Generally/Not otherwise specified Typical findings, called "vacuolar interface dermatitis":[6]
  • Mild inflammatory cell infiltrate along the dermoepidermal junction (black arrow in image)
  • Vacuolization within the basal keratinocytes (white arrow in image)
  • Often necrotic, predominantly basal, individual keratinocytes, manifesting as colloid or Civatte bodies
Vacuolar interface dermatitis, annotated.jpg
Acute graft-versus-host-disease
  • Vacuolar alteration of various severity, from focal or diffuse vacuolation of the basal keratinocytes (grade I), to separation at the dermoepidermal junction (grade III)
  • Involvement of the hair follicle[6]
  • Rarely eosinophils[6]
Micrographs of grades of skin graft-versus-host-disease.jpg
Allergic drug reaction
  • Rarely involvement of hair follicles.[6]
  • Frequently eosinophils[6]
Spongiotic dermatitis from drug allergy.jpg
Lichen sclerosus Hyperkeratosis, atrophic epidermis, sclerosis of dermis and dermal lymphocytes.[7] Micrograph of lichen sclerosus.jpg
Erythema multiforme
Lupus erythematosis Typical findings in systemic lupus erythematosus:[8]
  • Fibrinoid necrosis at the dermoepidermal junction
  • Liquefactive degeneration and atrophy of the epidermis
  • Mucin deposition in the reticular dermis
  • Edema, small hemorrhages
  • Mild and mainly lymphocytic infiltrate in the upper dermis
  • Fibrinoid material in the dermis around capillary blood vessels, on collagen and in the interstitium
  • In non-bullous cases, perivascular and interstitial neutrophils are sometimes present in the upper dermis, with damage to blood vessels
Histopathology of systemic lupus erythematosus.jpg Butterfly rash of lupus erythematosus.jpg

An interface dermatitis with vacuolar alteration, not otherwise specified, may be caused by viral exanthems, phototoxic dermatitis, acute radiation dermatitis, erythema dyschromicum perstans, lupus erythematosus and dermatomyositis.[1]

Further information: Vacuolar interface dermatitis

Interface dermatitis with lichenoid inflammation
Main conditions[1] Characteristics Micrograph Photograph
Generally/Not otherwise specified Typical findings:[1]
  • In the papillary dermis: a confluent, band-like, dense inflammation of mainly small lymphocytes and a few histiocytes, along or hugging the dermoepidermal junction.
  • Often vacuolar degeneration of basal keratinocytes and apoptotic bodies (colloid or Civatte bodies).
Lichen planus Irregular epidermal hyperplasia with a jagged “sawtooth” appearance, compact hyperkeratosis or orthokeratosis, foci of wedge-shaped hypergranulosis, basilar vacuolar degeneration, slight spongiosis in the spinous layer, and squamatization. The dermal papillae between the elongated rete ridges are frequently dome shaped. Necrotic keratinocytes can be observed in the basal layer of the epidermis and at the dermal-epidermal junction. Eosinophilic remnants of anucleate apoptotic basal cells may also be found in the dermis and are referred to as “colloid or civatte bodies”. Whickham striae are usually seen in the areas of hypergranulosis. Vacuolar degeneration at the basal layer may be noted leading to focal subepidermal clefts (Max Joseph spaces). Squamatization occurs as a result of maturation and flattening of cells in the basal layer. It happens in areas of marked hypergranulosis with prominence of the sawtooth pattern of rete ridges. Wedge-shaped hypergranulosis can occur in the eccrine ducts (acrosyringia) or hair follicles (acrotrichia). In the hypertrophic subtype, the associated hyperkeratosis, parakeratosis, hypergranulosis, papillomatosis, acanthosis, and hyperplasia markedly increased with thicker collagen bundles forming in the dermis. Moreover, the rete ridges are more elongated and rounded as opposed to the typical sawtooth pattern. In atrophic LP, loss of the rete ridges and dermal fibrosis is prominent. In vesiculobullous LP, the disease progression is quicker. Hence, some of the distinctive features such as hyperkeratosis, hypergranulosis, or dense lymphocytic dermal-epidermal infiltrate may not be present. LP lesion may resolve with residual hyperpigmentation caused by a persistent increase in the number of melanophages in the papillary dermis.[9] Histopathology of lichen planus.jpg Lichen planus 1.jpg
Lichenoid drug reaction

Can virtually be indistinguishable from cutaneous LP both clinically and histopathologically.

  • Typically, lesions have a photodistribution in the absence of oral mucosal involvement.[9]
  • Characteristically parakeratosis, a dermal eosinophilic infiltrate, and a perivascular lymphocytic infiltrate affecting the reticular dermis.
  • Epidermal changes are less common in lichenoid drug eruptions when compared to classic lichen planus. However, a higher concentration of necrotic keratinocyte and eosinophils in the infiltrate can be helpful in distinguishing lichenoid drug reaction from cutaneous lichen planus. A lengthy interval between the commencement of drug therapy and the onset of lesions does not exclude a diagnosis of lichenoid drug reaction. Resolution of the lesions often occurs within weeks to months after discontinuation of the offending drug.[9]
Histopathology of lichenoid drug reaction.jpg
Lichen nitidus
  • Localized granulomatous lymphohistiocytic infiltrate in an expanded dermal papilla.
  • Thinning of overlying epidermis and downward extension of the rete ridges at the lateral margin of the infiltrate, resulting in a typical "claw clutching a ball" appearance.[10]
Histopathology of lichen nitidus.jpg Photography of lichen nitidus.jpg
Lichen amyloidosus Presence of amyloid, possibly with direct immunofluorescence and Congo red staining.[11]
Congo red.

Interface dermatitis with lichenoid inflammation, not otherwise specified, can be caused by lichen planus-like keratosis, lichenoid actinic keratosis, lichenoid lupus erythematosus, lichenoid GVHD (chronic GVHD), pigmented purpuric dermatosis, pityriasis rosea, and pityriasis lichenoides chronica.[1] Unusual conditions that can be associated with a lichenoid inflammatory cell infiltrate are HIV dermatitis, syphilis, mycosis fungoides, urticaria pigmentosa, and post-inflammatory hyperpigmentation.[1] In cases of post-inflammatory hyperpigmentation, it is important to exclude potentially harmful mimics such as a regressed melanocytic lesion or lichenoid pigmented actinic keratosis.[1]

Psoriaform dermatitis

Examining multiple deeper levels is recommended if initial cuts do not correlate well with the clinical history.[1]

Psoriaform dermatitis typically displays:[1]

  • Regular epidermal hyperplasia, elongation of the rete ridges, hyperkeratosis, and parakeratosis.
  • Usually:A superficial perivascular inflammatory infiltrate
  • Often: Thinning of epidermal cells overlying the tips of dermal papillae (suprapapillary plates), and dilated, tortuous blood vessels within these papillae

Further histopathologic diagnosis is performed by the following parameters:

Psoriasiform dermatitis[1]
Condition Hyperkeratosis Parakeratosis Acanthosis Suprapapillary plate Spinous cell layer changes Other distinctive feature Micrograph
Psoriasis Present Diffuse Regular Thin Increased mitoses; minimal spongiosis
Clubbed rete pegs[12] [13]
  • Microabscesses
  • Thin or absent granular cell layer
Micrograph of psoriasis vulgaris.jpg
Psoriasiform drug reaction Present Focal Regular and irregular Normal or thick Spongiosis; eosinophilic infiltrate Basal cell layer with inflammatory cells; Civatte bodies
Chronic allergic/contact and atopic dermatitis Present Focal; crust may be present Irregular Normal or thick Spongiosis; eosinophilic infiltrate
Fungal infection Compact Focal; crust may be present Irregular Normal or thick Occasional neutrophiles;
Lichen simplex chronicus Present Focal; thick crust Regular or irregular Thin or thick ±minimal inflammatory infiltrate Thickened granular cell layer
Scabies Present Focal or diffuse Irregular Normal or thick Inflammatory infiltrate; eosinophilic spongiosis
Seborrheic dermatitis and HIV dermatitis Present Focal Irregular Normal or thick Spongiosis; lymphocytic and neutrophilic infiltrate
Pityriasis rubra pilaris Compact Shoulder parakeratosis[note 4]; alternating orthokeratosis and parakeratosis Regular or irregular Normal or thick Spongiosis; lymphocytic infiltrate; rare acantholysis
Pityriasis rosea Present Focal Irregular Normal or thick Small foci of spongiosis; lymphocytic infiltrate Occasional necrotic keratinocytes of basal layer
Syphilis Present Focal Regular or irregular Normal or thick Lymphocytes and neutrophils Basal layer interface change
Pityriasis lichenoides chronica Present Caps of parakeratosis Irregular Normal Mild spongiosis, lymphocytic infiltrate; necrotic keratinocytes Necrotic keratinocytes of basal layer
Mycosis fungoides Present Focal Regular or irregular Normal Minimal or no spongiosis; ±Pautrier microabscess Atypical lymphoid cells lining the dermo–epidermal junction
Pautrier microabscesses

Non vesicullobullous, non-pustular lesions without epidermal changes

Lymphocytic infiltrate

Main conditions[1] Characteristics Micrograph Photograph
Urticaria, lymphocyte predominant Perivascular location. Mast cells are relatively sparse, potentially demonstrated with special stains, preferably tryptase stain. Extravasated erythrocytes are present in about 50% of the cases. No vasculitis.[14] Micrograph of urticaria.jpg Dermal edema [solid arrows in (A,B)] and a sparse superficial predominantly perivascular and interstitial infiltrate of lymphocytes and eosinophils without signs of vasculitis (dashed arrow).[15] Urticaria near navel.jpg
Fungal skin infection Often visible fungus. Other signs depend on fungus species.[16]
Pigmented purpuric dermatosis
  • Perivascular infiltrate, but may involve the dermis, further away from blood vessels.[17]
  • Sometimes tendency for lichenoid infiltrate[note 5][17]
  • Mild vascular damage, mainly endothelial swelling and focal karyorrhectic debris.[17]
  • Red blood cell extravasation.[17]
  • The epidermis may be normal or may exhibit spongiosis, focal parakeratosis, exocytosis and/or vacuolar change.[17]
Histopathology of Schamberg disease.jpg Schambergdisease-26male.png
Erythema annulare centrifugum
  • Superficial types:[18]
  • Mild spongiosis, parakeratosis and microvesiculation.
  • "Coat-sleeve anomaly": tight lymphohistiocytic infiltrate surrounding superficial vessels

Deep lesions: Sharply demarcated perivascular mononuclear cell infiltrate in middle to deep dermis[18]

Micrograph of erythema annulare centrifugum.jpg Erythema annulare centrifugum on arms and legs.jpg
Not otherwise specified[note 3] A lesion with superficial lymphocytic infiltrate without additional histopathologic characteristics can be due to for example drug reactions and insect bites.[1][note 3]

Lymphoeosinophilic infiltrate

Main conditions[1] Characteristics Micrograph Photograph
Urticaria, lymphocyte predominant Perivascular location. Mast cells are relatively sparse, potentially demonstrated with special stains, preferably tryptase stain. Extravasated erythrocytes are present in about 50% of the cases. No vasculitis.[14] Micrograph of urticaria.jpg Dermal edema (solid arrows) and a sparse superficial predominantly perivascular and interstitial infiltrate of lymphocytes and eosinophils (dashed arrow) Urticaria near navel.jpg
Prevesicular stage of bullous pemphigoid Image at right shows influx of inflammatory cells including eosinophils and neutrophils in the dermis (solid arrow) and blister cavity (dashed arrows), and deposition of fibrin (asterisks).[19] However, the diagnosis of bullous pemphigoid consist of at least 2 positive results out of 3 criteria:[20]
  • Pruritus and/or predominant cutaneous blisters
  • Linear IgG and/or C3c deposits (in an n- serrated pattern) by direct immunofluorescence microscopy (DIF)
  • Positive epidermal side staining by indirect immunofluorescence microscopy on human salt-split skin (IIF SSS) on a serum sample.
Micrograph of infiltrate in bullous pemphigoid.jpg
Not otherwise specified[note 3] A lesion with superficial lymphoeosinophilic infiltrate without additional histopathologic characteristics can be due to for example drug reactions and insect bites.[1][note 3]

Lymphoplasmacytic infiltrate

Main conditions[1] Characteristics Micrograph Photograph
Rosacea Typically enlarged, dilated capillaries and venules located in the upper dermis, angulated telangiectasias, perivascular and perifollicular lymphocytic infiltration, and superficial dermal edema.[21] Micrograph of rosacea.jpg Rosacea.jpg
Secondary syphilis Various, but often one or a combination of:[22]
  • Psoriasiform hyperplasia with superficial neutrophils
  • Lichenoid tissue reaction, epidermal apoptosis and exocytosis of neutrophils
  • Superficial and deep chronic infiltrate in the dermis
  • Often numerous plasma cells in about 1/3 of cases
  • Often endothelial swelling.
Micrograph of secondary syphilis, HE.jpg Secondary stage syphilis sores (lesions) on the soles of the feet. Plantar lesions-CDC.jpg
Erythema migrans Typically a superficial and deep perivascular lymphocytic infiltrate.[23] Plasma cells are typically located at the periphery of the lesion, whereas eosinophils are in the center.[23] Erythema migrans - erythematous rash in Lyme disease - PHIL 9875.jpg
Kaposi’s sarcoma in patch stage The patch stage typically shows irregular proliferation of jagged vascular channels in the dermis below an integral epidermis. The so-called promontory sign is sometimes found in patch stage lesions and denotes vascular spaces surrounding pre-existing blood (see image).[24]

vessels

Micrograph of promontory sign of kaposi's sarcoma.jpg Patch stage Kaposi's sarcoma.jpg
Not otherwise specified[note 3] A lesion with superficial lymphoplasmacytic infiltrate without additional histopathologic characteristics can be due to for example trauma, ulceration, scar and early cutaneous connective tissue diseases.[1][note 3]

Mastocytosis

Main conditions[1] Characteristics Micrograph Photograph
Urticaria pigmentosa Mastocytosis with a clinical picture of darkish spots. Histopathology of urticaria pigmentosa.jpg Urticaria pigmentosa lesions on a child.jpg
Not otherwise specified[note 3] Includes the rare disease of primary mastocytosis.[1][note 3]

Lymphohistiocytic infiltrate

Leprosy

These include bacterial infections including leprosy, and the sample should therefore be stained with Ziel-Neelsen, acid fast stains, Gomori methenamine silver, PAS, and Fite stains.[1] If negative, an unspecific lymphohistocytic dermatosis may be caused by drug reactions and viral infections.[1][note 3]

Granulomatous inflammation

Further information: Granulomatous skin inflammation Granulomatous inflammation is defined by the presence of mononuclear leukocytes, specifically histiocytes, appearing as epithelioid cells with round to oval nuclei, often with irregular contours and abundant granular eosinophilic cytoplasm with indistinct cell borders. They may also coalesce to form multinucleated giant cells.[25]

Neutrophilic infiltrate

Main conditions[1] Characteristics Micrograph Photograph
Urticaria, neutrophil predominant
  • Interstitial location[14]
  • Relatively dense infiltrate[14]
  • Mast cells are relatively sparse, potentially demonstrated with special stains, preferably tryptase stain.[14]
  • Extravasated erythrocytes are present in about 50% of the cases [14]
  • No vasculitis.[14]
Micrograph of neutrophilic urticarial dermatosis.jpg Neutrophilic urticarial dermatosis.jpg
Dermatitis herpetiformis
  • Subepidermal vesicles and blisters associated with accumulation of neutrophils at the papillary tips.[26]
  • Sometimes presence of eosinophils, giving an appearance similar to bullous pemphigoid.[26]
  • The histopathology is unspecific in approximately 35%–40% of the cases,[26] and direct immunofluorescence is needed, showing deposition of IgA in the papillary dermis in a granular or fibrillar pattern.[27]
Micrograph of dermatitis herpetiformis.jpg Dermatitis herpetiformis.jpg
Early linear IgA bullous dermatosis Subepidermal blister formation.[28] Micrograph of linear IgA bullous dermatosis.jpg Linear IgA bullous dermatosis.jpg
Early febrile neutrophilic dermatosis (Sweet's syndrome) Neutrophilic and lymphohistiocytic infiltrate and edema.[29] Sweet's syndrome pathology.jpg Sweet's syndrome Crohn's disease.gif
Connective tissue disorders
  • Usually associated with epidermal changes.[1] (Systemic lupus erythematosis pictured)
Histopathology of systemic lupus erythematosus.jpg Butterfly rash of lupus erythematosus.jpg
Cutaneous small-vessel vasculitis
  • Neutrophils with nuclear dust (dashed arrows in image), with high affinity for postcapillary venules.[30]
  • Features of vascular injury: fibrinoid necrosis (asterisks) and erytrocyt extravasation (solid arrows)
Micrograph of cutaneous small-vessel vasculitis.jpg Cutaneous small-vessel vasculitis.jpg
Acute inflammation (not otherwise specified)
  • Neutrophilic infiltrate not conforming to any of the above mentioned conditions.
Dermal edema in a case of cellulitis.

No visible pathology

In a referral with a rash or other suspicion of dermatitis, but no visible pathology is seen, generally do a fungal stain, as fungal infections may have no visible pathology on H&E stain.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. PAS is for evaluation of the epidermal basement membrane, blood vessels, and the presence of fungal organisms
  3. 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 In "not otherwise specified" cases, a description of the findings attained so far is generally enough as a diagnosis, but may mention when it can be consistent with a diagnosis that is clinically suspected according to the referral. A more comprehensive approach is to include a comment such as the following:
    "Differential diagnosis for this condition include: ____, ____ and ____. Clinical correlation is recommended.
  4. Parakeratotic mounds at the edge of follicular ostia.
  5. Pigmented purpuric dermatitis of Gougerot and Blum particularly have a tendency for lichenoid infiltrate.

Main page

References

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 1.23 1.24 1.25 1.26 1.27 1.28 1.29 1.30 1.31 1.32 1.33 1.34 1.35 Alsaad, K O (2005). "My approach to superficial inflammatory dermatoses ". Journal of Clinical Pathology 58 (12): 1233–1241. doi:10.1136/jcp.2005.027151. ISSN 0021-9746. 
  2. Page 678 in: Chhabra, Seema; Minz, RanjanaWalker; Saikia, Biman (2012). "Immunofluorescence in dermatology ". Indian Journal of Dermatology, Venereology, and Leprology 78 (6): 677. doi:10.4103/0378-6323.102355. ISSN 0378-6323. Archived from the original. . 
  3. Katarzyna Lundmark, Krynitz, Ismini Vassilaki, Lena Mölne, Annika Ternesten Bratel. Handläggning av hudprover – provtagningsanvisningar, utskärningsprinciper och snittning (Handling of skin samples - Instructions for sampling, cutting and incision. KVAST (Swedish Society of Pathology). Retrieved on 2019-09-09.
  4. ". Ochsner J 5 (2): 22–33. 2003. PMID 22826680. PMC: 3399331. Archived from the original. . 
    - With a "standard histologic examination" that, in addition to the lesion, only includes one section from each side along the longest diameter of the specimen.
    - It also shows an example of circular coverage, with equal coverage distance in all four directions.
    - The entire specimen may be submitted if the risk of malignancy is high.
  5. 5.0 5.1 5.2 Mowafak Hamodat. Skin inflammatory (nontumor) > Spongiotic, psoriasiform and pustular reaction patterns > Seborrheic dermatitis. PathologyOutlines.com. Topic Completed: 1 August 2011. Revised: 26 March 2019
  6. 6.0 6.1 6.2 6.3 6.4 6.5 Unless else specified in boxes, reference is: Alsaad, K O (2005). "My approach to superficial inflammatory dermatoses ". Journal of Clinical Pathology 58 (12): 1233–1241. doi:10.1136/jcp.2005.027151. ISSN 0021-9746. 
  7. Lisa K Pappas-Taffer. Lichen Sclerosus. Medscape. Updated: May 17, 2018
  8. Mowafak Hamodat. Skin inflammatory (nontumor) > Lichenoid and interface reaction patterns > Lupus: systemic lupus erythematosus (SLE). PathologyOutlines. Topic Completed: 1 August 2011. Revised: 26 March 2019
  9. 9.0 9.1 9.2 Gorouhi, Farzam; Davari, Parastoo; Fazel, Nasim (2014). "Cutaneous and Mucosal Lichen Planus: A Comprehensive Review of Clinical Subtypes, Risk Factors, Diagnosis, and Prognosis ". The Scientific World Journal 2014: 1–22. doi:10.1155/2014/742826. ISSN 2356-6140. 
    - Attribution 3.0 Unported (CC BY 3.0)
  10. "Generalized lichen nitidus ". Pediatr Dermatol 22 (2): 158–60. 2005. doi:10.1111/j.1525-1470.2005.22215.x. PMID 15804308. 
  11. Shenoi, SD; Balachandran, C; Mehta, VandanaRai; Salim, T (2005). "Lichen amyloidosus: A study of clinical, histopathologic and immunofluorescence findings in 30 cases ". Indian Journal of Dermatology, Venereology and Leprology 71 (3): 166. doi:10.4103/0378-6323.16230. ISSN 0378-6323. 
  12. "Cytokines and cytokine profiles in human autoimmune diseases and animal models of autoimmunity ". Mediators of Inflammation 2009: 1–20. 2009. doi:10.1155/2009/979258. PMID 19884985. 
  13. "Diagnosis and classification of psoriasis ". Autoimmunity Reviews 13 (4–5): 490–5. January 2014. doi:10.1016/j.autrev.2014.01.008. PMID 24434359. 
  14. 14.0 14.1 14.2 14.3 14.4 14.5 14.6 Barzilai, Aviv; Sagi, Lior; Baum, Sharon; Trau, Henri; Schvimer, Michael; Barshack, Iris; Solomon, Michal (2017). "The Histopathology of Urticaria Revisited—Clinical Pathological Study ". The American Journal of Dermatopathology 39 (10): 753–759. doi:10.1097/DAD.0000000000000786. ISSN 0193-1091. 
  15. Giang, Jenny; Seelen, Marc A. J.; van Doorn, Martijn B. A.; Rissmann, Robert; Prens, Errol P.; Damman, Jeffrey (2018). "Complement Activation in Inflammatory Skin Diseases ". Frontiers in Immunology 9. doi:10.3389/fimmu.2018.00639. ISSN 1664-3224. 
  16. Guarner, J.; Brandt, M. E. (2011). "Histopathologic Diagnosis of Fungal Infections in the 21st Century ". Clinical Microbiology Reviews 24 (2): 247–280. doi:10.1128/CMR.00053-10. ISSN 0893-8512. 
  17. 17.0 17.1 17.2 17.3 17.4 Stephen Lyle. Pigmented purpuric dermatoses. Dermpedia.org. Retrieved on 2019-11-05.
  18. 18.0 18.1 . Histology of erythema annulare centrifugum. DermNet NZ. Retrieved on 2019-11-05.
  19. Giang, Jenny; Seelen, Marc A. J.; van Doorn, Martijn B. A.; Rissmann, Robert; Prens, Errol P.; Damman, Jeffrey (2018). "Complement Activation in Inflammatory Skin Diseases ". Frontiers in Immunology 9. doi:10.3389/fimmu.2018.00639. ISSN 1664-3224. 
  20. "Assessment of diagnostic strategy for early recognition of bullous and nonbullous variants of pemphigoid. ". JAMA Dermatol 155 (2): 158–165. December 2018. doi:10.1001/jamadermatol.2018.4390. PMID 30624575. 
  21. Celiker, Hande; Toker, Ebru; Ergun, Tulin; Cinel, Leyla (2017). "An unusual presentation of ocular rosacea ". Arquivos Brasileiros de Oftalmologia 80 (6). doi:10.5935/0004-2749.20170097. ISSN 0004-2749. 
  22. Assoc Prof Patrick Emanuel (2013). Syphilis pathology. Dermnet NZ.
  23. 23.0 23.1 Wilson, Thomas C.; Legler, Allison; Madison, Kathi C.; Fairley, Janet A.; Swick, Brian L. (2012). "Erythema Migrans ". The American Journal of Dermatopathology 34 (8): 834–837. doi:10.1097/DAD.0b013e31825879be. ISSN 0193-1091. 
  24. Soyer, H. Peter; Jakob, Lena; Metzler, Gisela; Chen, Ko-Ming; Garbe, Claus (2011). "Non-AIDS Associated Kaposi's Sarcoma: Clinical Features and Treatment Outcome ". PLoS ONE 6 (4): e18397. doi:10.1371/journal.pone.0018397. ISSN 1932-6203. 
  25. Shah, Kabeer K.; Pritt, Bobbi S.; Alexander, Mariam P. (2017). "Histopathologic review of granulomatous inflammation ". Journal of Clinical Tuberculosis and Other Mycobacterial Diseases 7: 1–12. doi:10.1016/j.jctube.2017.02.001. ISSN 24055794. 
  26. 26.0 26.1 26.2 Antiga, Emiliano; Caproni, Marzia (2015). "The diagnosis and treatment of dermatitis herpetiformis ". Clinical, Cosmetic and Investigational Dermatology: 257. doi:10.2147/CCID.S69127. ISSN 1178-7015. 
  27. Huma A. Mirza; Amani Gharbi; William Gossman.. Dermatitis Herpetiformis. StatPearls at National Center for Biotechnology Information. Last Update: July 11, 2019.
  28. Saleem, Maryam; Iftikhar, Hassaan (2019). "Linear IgA Disease: A Rare Complication of Vancomycin ". Cureus. doi:10.7759/cureus.4848. ISSN 2168-8184. 
  29. Casarin Costa, Jose Ricardo; Virgens, Anangelica Rodrigues; de Oliveira Mestre, Luisa; Dias, Natasha Favoretto; Samorano, Luciana Paula; Valente, Neusa Yuriko Sakai; Festa Neto, Cyro (2017). "Sweet Syndrome: Clinical Features, Histopathology, and Associations of 83 Cases ". Journal of Cutaneous Medicine and Surgery 21 (3): 211–216. doi:10.1177/1203475417690719. ISSN 1203-4754. 
  30. Giang, Jenny; Seelen, Marc A. J.; van Doorn, Martijn B. A.; Rissmann, Robert; Prens, Errol P.; Damman, Jeffrey (2018). "Complement Activation in Inflammatory Skin Diseases ". Frontiers in Immunology 9. doi:10.3389/fimmu.2018.00639. ISSN 1664-3224. 
    • "Figures - available via license: CC BY 4.0"

Image sources


Benign non-inflammatory skin conditions

Author: Mikael Häggström [note 1]
These are aberrations that do not display signs of suspected malignant excisions or dermatitis. These may present as skin cysts.

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Gross processing

Gross pathology processing of skin lesions with benign appearance, by lesion size:[1]
<4 mm 4 - 8 mm 9 - 15 mm

Tissue selection from skin excision with lesion less than 4 mm with benign appearance.png

Tissue selection from skin excision with lesion 4-8 mm with benign appearance.png

Tissue selection from skin excision with lesion 9-15 mm with benign appearance.png

In table above, each top image shows recommended lines for cutting out slices to be submitted for further processing. Bottom image shows which side of the slice that should be put to microtomy. Dashed lines here mean that either side could be used. Further information: Gross processing of skin excisions

Microscopic evaluation

The primary objective is to determine the location, and then the most likely cell type of the aberration:

Epidermis

Dermis

Fatty tissue

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. ". Ochsner J 5 (2): 22–33. 2003. PMID 22826680. PMC: 3399331. Archived from the original. . 
    - With a "standard histologic examination" that, in addition to the lesion, only includes one section from each side along the longest diameter of the specimen.
    - It also shows an example of circular coverage, with equal coverage distance in all four directions.
    - The entire specimen may be submitted if the risk of malignancy is high.
  2. Sato, Toshitsugu; Tanaka, Masaru (2014). "Linear sebaceous hyperplasia on the chest ". Dermatology Practical & Conceptual. doi:10.5826/dpc.0401a16. ISSN 21609381. 
  3. Rabello, FB; Souza, CD; Farina Jr, JA (2014). "Update on hypertrophic scar treatment ". Clinics 69 (8): 565–573. doi:10.6061/clinics/2014(08)11. ISSN 18075932. 

Image sources


Keloid

Author: Mikael Häggström [note 1]

Gross processing

Gross pathology processing of skin lesions with benign appearance, by lesion size:[1]
<4 mm 4 - 8 mm 9 - 15 mm

Tissue selection from skin excision with lesion less than 4 mm with benign appearance.png

Tissue selection from skin excision with lesion 4-8 mm with benign appearance.png

Tissue selection from skin excision with lesion 9-15 mm with benign appearance.png

In table above, each top image shows recommended lines for cutting out slices to be submitted for further processing. Bottom image shows which side of the slice that should be put to microtomy. Dashed lines here mean that either side could be used. Further information: Gross processing of skin excisions

Microscopic evaluation

A keloid is characterized by wide bands of collagen with large, brightly eosinophilic, glassy fibers, parallel to fibroblasts and myofibroblasts.
Keloid versus hypertrophic scar - Typical findings
Keloid Hypertrophic scar
Histopathology of a keloid.jpg Histopathology of a hypertrophic scar, medium magnification.jpg
Flattening of the overlying epidermis No Yes
Scarring of the papillary dermis No Yes
Collagen Thick hyalinized bundles Whorl-like or nodular arrangements
Vertically oriented blood vessels Yes No
Prominent disarray of fibrous fascicles/nodules Yes No
Tongue-like advancing edge underneath normal-appearing epidermis and papillary dermis Yes No
Horizontal cellular fibrous band in the upper reticular dermis Yes No
Prominent fascia-like fibrous band Yes No

Reporting

Example report:

Skin, left earlobe, excision:
- Keloid

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. ". Ochsner J 5 (2): 22–33. 2003. PMID 22826680. PMC: 3399331. Archived from the original. . 
    - With a "standard histologic examination" that, in addition to the lesion, only includes one section from each side along the longest diameter of the specimen.
    - It also shows an example of circular coverage, with equal coverage distance in all four directions.
    - The entire specimen may be submitted if the risk of malignancy is high.

Image sources


Hypertrophic scar

Author: Mikael Häggström [note 1]

Gross processing

Gross pathology processing of skin lesions with benign appearance, by lesion size:[1]
<4 mm 4 - 8 mm 9 - 15 mm

Tissue selection from skin excision with lesion less than 4 mm with benign appearance.png

Tissue selection from skin excision with lesion 4-8 mm with benign appearance.png

Tissue selection from skin excision with lesion 9-15 mm with benign appearance.png

In table above, each top image shows recommended lines for cutting out slices to be submitted for further processing. Bottom image shows which side of the slice that should be put to microtomy. Dashed lines here mean that either side could be used. Further information: Gross processing of skin excisions

Microscopic evaluation

A hypertrophic scar is characterized by replacement of the papillary and reticular dermis by scar tissue with prominent vertically oriented blood vessels.[2]
Keloid versus hypertrophic scar - Typical findings
Keloid Hypertrophic scar
Histopathology of a keloid.jpg Histopathology of a hypertrophic scar, medium magnification.jpg
Flattening of the overlying epidermis No Yes
Scarring of the papillary dermis No Yes
Collagen Thick hyalinized bundles Whorl-like or nodular arrangements
Vertically oriented blood vessels Yes No
Prominent disarray of fibrous fascicles/nodules Yes No
Tongue-like advancing edge underneath normal-appearing epidermis and papillary dermis Yes No
Horizontal cellular fibrous band in the upper reticular dermis Yes No
Prominent fascia-like fibrous band Yes No

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. ". Ochsner J 5 (2): 22–33. 2003. PMID 22826680. PMC: 3399331. Archived from the original. . 
    - With a "standard histologic examination" that, in addition to the lesion, only includes one section from each side along the longest diameter of the specimen.
    - It also shows an example of circular coverage, with equal coverage distance in all four directions.
    - The entire specimen may be submitted if the risk of malignancy is high.
  2. Rabello, FB; Souza, CD; Farina Jr, JA (2014). "Update on hypertrophic scar treatment ". Clinics 69 (8): 565–573. doi:10.6061/clinics/2014(08)11. ISSN 18075932. 

Image sources


Arteries

Author: Mikael Häggström [note 1]

Presentations

Gross processing

A minimal gross processing of arteries includes a longitudinal dissection and inspection of tunica intima.

Consecutive cross-sections allows for a detection and estimation of atherosclerotic stenosis.

Plaque at different degrees of atherosclerotic stenosis.

Microscopic examination

  • Confirm that it is actually an artery (may be a vein, and a neuron may look grossly like a small artery).
  • Look for atherosclerosis and thrombosis.
  • Classify atherosclerosis as mild, moderate or severe.
  • If cross-sections were made, estimate the maximum percentage of occlusion for each artery.
Evaluate for giant cell arteritis at least upon request. It is characterized by a granulomatous inflammation of arteries with discontinuous and fragmented internal elastic lamina.[2]

Microscopy report

  • Classify any atherosclerosis as mild, moderate or severe.
  • If cross-sections were made, state the maximum percentage of stenosis for each artery.

Example:

Sections of the three main coronary arteries reveal << mild / moderate / severe>> atherosclerosis, with approximately __%, __% and __% stenosis of the left anterior descending, left circumflex coronary artery and right coronary artery, respectively.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. 1.0 1.1 1.2 1.3 1.4 Yang, Wen Jie; Fisher, Mark; Zheng, Lu; Niu, Chun Bo; Paganini-Hill, Annlia; Zhao, Hai Lu; Xu, Yun; Wong, Ka Sing; et al. (2017). "Histological Characteristics of Intracranial Atherosclerosis in a Chinese Population: A Postmortem Study ". Frontiers in Neurology 8. doi:10.3389/fneur.2017.00488. ISSN 1664-2295. 
  2. Nat Pernick, M.D.. Eye - Orbit & optic nerve - Temporal arteritis. PathologyOutlines. Last author update: 1 February 2014. Last staff update: 29 December 2020

Image sources


Thrombus

Author: Mikael Häggström [note 1]

Composition of a fresh thrombus.

Microscopic evaluation

An organizing thrombus.[1]

Look for presence of fibroblasts or myofibroblasts, conferring a diagnosis of an organizing thrombus.

Reporting

Example:

Right profunda femoris artery clot, excision: Organizing thrombus.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Picture from:Pantanowitz, Liron; Duke, Wayne H (2008). "Intravascular lesions of the hand ". Diagnostic Pathology 3 (1): 24. doi:10.1186/1746-1596-3-24. ISSN 1746-1596. 
    - "Figure- available via license: Creative Commons Attribution 2.0 Generic"

Image sources


Aneurysm

Author: Mikael Häggström [note 1]

Cross-section of an arterial aneurysm, showing most of the area consisting of organized mural thrombus (tan-brown area).

Gross processing

  • Describe the shape (generally either fusiform or saccular).
  • Measure the length and diameter

Make several cross-sections and look for any dissection in the wall.

Gross report

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))
(( A. Labeled -left upper extremity aneurysm. The specimen is received in formalin and consists of a segment of)) fusiformly dilated vessel measuring 11.5 cm in length and the diameter is 6.5 (x 6.5 cm). Upon sectioning, <<most \ (( __ %))>> of the area is occupied by tan-yellow to tan-red non-homogenous surface, consistent with an organized mural thrombus. (No visible wall dissection.)

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References


Image sources


Soft tissues

Tophus/gout

Author: Mikael Häggström [note 1]

Preparation

A tophus specimen should be sent dry to the pathology department, and not be put in formalin.[note 2]

Gross processing

A large tophus.

Preferably make a touch prep for polarized light microscopy. At least if urate crystals are not initially detected, take sections to be put in 100% alcohol and tell the histology lab to prepare it as per gout protocol.[note 2] With characteristic crystals on a touch prep, sections may possibly be submitted in formalin.[note 2]

Microscopy evaluation

On a touch prep, look for needle-shaped crystals of urate. On polarized light, these will have negative birefriengence.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. 2.0 2.1 2.2 Formalin dissolves the crystals.

Main page

References

  1. Bruce M Rothschild. Gout and Pseudogout Workup. Medscape. Updated: Jun 30, 2020

Image sources


Peripheral nerve sheath tumor

  1. REDIRECT Soft tissue tumor

Lipomatous tumor

Author: Mikael Häggström [note 1]

Lipomatous tumor.

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Gross processing

  • Perform consecutive slicing of the entire specimen.
  • Look for signs of liposarcoma: Mainly by firm volumes.[1] Color varies from yellow to white (and firm) depending on the proportion of adipocytic, fibrous and/or myxoid content.[2] Areas of fat necrosis are common in larger lesions. Rarely, infiltrative growth is seen.[2]
  • Submit slices from any suspicious parts, or at least one representative slice from the specimen.[3] (A more comprehensive practice is to submit 1 section per centimeter, and 2 sections per cassette.[4])

Gross report

  • Color
  • Even absence of hemorrhage or necrosis.

Example:

Mass ((weighing 121 grams)) and measuring 10 x 6,5 x 3,5 cm. ((The surgical margin is intact.)) Cut sections show homogenous yellow color, with no hemorrhage or necrosis. ((The specimen is serially sectioned, and representative sections are submitted for microscopic examination in __ cassettes.))
  See also: General notes on gross processing

Microscopic evaluation

A pedunculated lipomatous skin tumor may be a pedunculated lipofibroma:

For atypical cases and as a non-subspecialist in soft tissue pathology, generally seek expert opinion, including further workup.

Microscopy/Histopathology report

For lipomas: (Absence of signs of malignancy.)

Histopathology of lipoma.jpg
(Chest wall, left lateral, excision:)
  • Lipoma.
  • (Negative for malignancy)

((Microscopic description: Tissue composed of univacuolar fat cells and delicate and inconspicuous fibrous septa.))

  See also: General notes on reporting

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Monica Dahlgren, Janne Malina, Anna Måsbäck, Otto Ljungberg (1997-02-13). Lilla utskärningen.
  2. 2.0 2.1 Andreas F Mavrogenis, Panayiotis J Papagelopoulos (2013-02-01). Soft Tissues: Well-differentiated liposarcoma. Atlas of Genetics and Cytogenetics in Oncology and Haematology.
  3. Pathology Department at NU Hospital Group, Sweden, 2019-2020.
  4. . Lipoma. Gross Pathology Manual - By The University of Chicago Department of Pathology. Retrieved on 2020-08-26.
  5. . Lipoma Variant: Fibrolipoma. Stanford University School of Medicine. Retrieved on 2020-02-10.
  6. Vijay Shankar. Soft tissue - Adipose tissue tumors - Lipoma and variants - Angiolipoma. Pathology Outlines. Topic Completed: 1 August 2012. Minor changes: 20 March 2019
  7. Michael R. Clay, M.D.. Liposarcoma. PathologyOutlines. Topic Completed: 1 November 2017. Minor changes: 11 May 2021
  8. Michael R. Clay. Soft tissue - Adipose tissue - Myxoid liposarcoma. PathologyOutlines. Topic Completed: 1 January 2018. Revised: 20 March 2019

Image sources


Hernia sac

Author: Mikael Häggström [note 1]

Gross pathology of a hernia sac.

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Fixation

Generally 10% neutral buffered formalin.

Gross processing

A gross inspection is almost always enough, and tissue generally does not need to be submitted except in unique circumstances.[1] ((Still you may submit 1 cassette of one or more representative sections for an inguinal hernia sac in a patient aged up to 16 years of age, or in case of hernia sacs from other regions than inguinal.))

Gross report
((A. Labeled - ___. The specimen is received in formalin and consists of)) __ fragment(s) of pink-tan fibromembranous tissue, measuring ___ cm in greatest dimension and ___ cm in greatest thickness. The surfaces are smooth. There are no sections submitted for microscopic examination. (Representative sections are submitted for microscopic examination in __ cassettes.)

Microscopic report

Mesothelial lining of a hernia sac.

In case of a gross only examination, the microscopic report may still be given as a formality:

Right inguinal region, herniorrhaphy:
Hernia sac, gross examination only.

When microscopy slides of the case are available, you may screen the sample at low magnification to rule out obvious pathology:

Umbilical hernia sac, hernia repair:
Connective tissue lined by mesothelium, consistent with hernia sac.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Chesley PM, Black GE, Martin MJ, Johnson EK, Maykel JA, Steele SR (2015). "The utility of pathologic evaluation of adult hernia specimens. ". Am J Surg 209 (5): 783-6; discussion 786. doi:10.1016/j.amjsurg.2014.12.019. PMID 25725504. Archived from the original. . 

Image sources


Oral

Jaw cysts

Author: Mikael Häggström [note 1]
Cystic changes in the jaw bones or around teeth:

Microscopic examination

Attempt to characterize the lining of the cyst. Look for important signs:

Signs

Any keratinization of the lining.

Any signs of malignancy. Further information: Evaluation of suspected malignancies

Diagnoses

Relative incidence of odontogenic cysts.[3]

All the following are odontogenic cyst, and in case of inability to specify further, may be simply diagnosed as such:

Cyst type Lining epithelium Other characteristics Image
Periapical (radicular) cyst Stratified squamous epithelium of variable thickness, except when originating in a maxillary sinus where there is respiratory epithelium (pseudostratified ciliated columnar epithelium).[1]
  • A fibrous capsule of varying thickness, with chronic inflammatory cells, wherein a plasma cells may be abundant.[1]

They sometimes have the following features:[1]

  • Cholesterol clefts in the cyst lining.
Histopathology of a periapical cyst, with metaplastic changes of mucous secreting cells (B), and ciliated cells (C).[4]
Non-inflamed dentigerous cyst
  • 2 - 4 layers of cuboidal epithelium, devoid of superficial keratinization.[2]
  • Sometimes partially a thin, fragmented layer of eosinophilic columnar cells or low cuboidal epithelium[2]
Typically:[2]
  • Fibrous to fibromyxoid connective tissue
  • No rete ridges, flat interface

They occasionally have:

  • Dystrophic calcifications
Histopathology of dentigerous cyst.jpg
Inflamed dentigerous cyst Hyperplastic non-keratinized epithelium[2] Typically:[2]
  • Fibrous connective tissue
  • Chronic inflammatory cells

Sometimes:[2]

  • Elongated interconnecting rete ridges
  • Cholesterol clefts, possibly cholesterol granuloma

They occasionally have:[2]

  • Dystrophic calcifications
Residual cyst Stratified squamous epithelium:[5]
  • May demonstrate exocytosis, spongiosis, and/or hyperplasia
  • May be discontinuous in part and range in thickness from 1 to 50 cell layers, but usually 6 - 20 cell layers

In early cysts, the epithelial lining tend to be proliferative and arcading, with an intense inflammation.
Established cysts tend to rather have fairly regular lining with a higher degree of differentiation, resembling a simple stratified squamous epithelium

Cyst lumen may demonstrate fluid and cellular debris.[5]

All types above can occasionally have scattered mucous or ciliated cells, as well as Rushton bodies, which are amorphic, eosinophilic, linear to crescent-shaped bodies in the cyst epithelium.[4][1][2][5]

Report

  • Type of lining
  • Other visible features
  • At least the most probable type of cyst.
  • Even absence of signs of malignancy

Example:

Histopathology of a periapical cyst, with metaplastic changes of mucous secreting cells, and ciliated cells.jpg
Parts of a cyst, lined by stratified squamous epithelium, with foci of mucous cells and ciliated cells. The underlying fibrous capsule contains cholesterol clefts and inflammation. No signs of malignancy.
- Benign odontogenic cyst of periapical type.
  See also: General notes on reporting

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. 1.0 1.1 1.2 1.3 1.4 Annie S. Morrison, Kelly Magliocca. Mandible & maxilla - Odontogenic cysts - Periapical (radicular) cyst. Pathology Outlines. Topic Completed: 1 March 2014. Revised: 13 December 2019
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 Kelly Magliocca, Annie S. Morrison. Mandible & maxilla - Odontogenic cysts - Dentigerous. Pathology Outlines. Topic Completed: 1 October 2013. Revised: 2 December 2019
  3. Leandro Bezerra Borges; Francisco Vagnaldo Fechine; Mário Rogério Lima Mota; Fabrício Bitu Sousa; Ana Paula Negreiros Nunes Alves (2012). "Odontogenic lesions of the jaw: a clinical-pathological study of 461 cases. ". Revista Gaúcha de Odontologia 60 (1). Archived from the original. . 
  4. 4.0 4.1 Tsesis, I; Rosen, E; Dubinsky, L; Buchner, A; Vered, M (2016). "Metaplastic changes in the epithelium of radicular cysts: A series of 711 cases ". Journal of Clinical and Experimental Dentistry: 0–0. doi:10.4317/jced.52846. ISSN 19895488. 
    - "Fig 2- available via license: Creative Commons Attribution 2.5 Generic"
  5. 5.0 5.1 5.2 Annie S. Morrison, Kelly Magliocca. Mandible & maxilla - Odontogenic cysts - Residual cyst. Pathology Outlines. Topic Completed: 1 April 2014. Revised: 13 December 2019

Image sources


Verrucous oral lesions

Author: Mikael Häggström [note 1]

Verrucous hyperplasia.

Verrucous oral lesions have hypergranulosis and/or hyperkeratosis as the most conspicuous finding.

Microscopic evaluation

Look for signs of koilocyte-like changes, which may indicate verrucous squamous cell carcinoma, and which typically only has low atypia:[1]

Verrucous squamous cell carcinoma (images are from penis).

If uncertain, perform immunohistochemistry for Ki67 and p53.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Initially copied from: Paolino, Giovanni; Donati, Michele; Didona, Dario; Mercuri, Santo; Cantisani, Carmen (2017). "Histology of Non-Melanoma Skin Cancers: An Update ". Biomedicines 5 (4): 71. doi:10.3390/biomedicines5040071. ISSN 2227-9059. 
    "This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/)."

Image sources


Tonsil

Author: Mikael Häggström [note 1]

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Gross processing

Gross pathology of a hypertrophic tonsil.

First look at the requisition form ((and in the medical records)) for the following suspicions:

  • Suspected infection: Confirm that a sample has been taken for microbiology. If not, take a sample from within the specimen when you gross it.
  • Possible lymphoma: Make a touch prep and take sample(s) for flow cytometry. If you have bilateral tonsils, and they look grossly similar, you may combine a small sample of each tonsil into one container for flow cytometry.
  • Suspected tumor: Ink the external surfaces before sectioning. Otherwise inking is not needed. Further information: Tumor

Inspect the tonsils for any significant gross focal changes. A representative section of the grossly most abnormal part from each tonsil is generally enough.

Example gross report
((A. Labeled - ___. The specimen is received in formalin and consists of)) one rubbery, ovoid, pink-tan tonsil(s) measuring ____. The mucosal surfaces are unremarkable. On sectioning, the tissue is tan-white and homogenous, with no gross lesions. (Representative sections are submitted for microscopic examination in __ cassettes.)

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References


Image sources


Salivary glands

Author: Mikael Häggström, M.D. [note 1]
The major salivary glands are the parotid, submandibular, and sublingual glands.

Evaluation

Look for the most common tumors:

Cytology

Reporting=

Example report:

Right parotid mass, biopsy:
– Pleomorphic adenoma.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. 1.0 1.1 Steve C Lee, MD, PhD. Salivary Gland Neoplasms. Medscape. Updated: Jan 13, 2021}}
    Diagrams by Mikael Häggström, MD
  2. Image by Mikael Häggström, MD. Reference for description: Bin Xu, M.D., Ph.D.. Pleomorphic adenoma. Pathology Outlines. Last author update: 30 July 2021. Last staff update: 6 February 2023
  3. Image by Mikael Häggström, MD. Reference for description: Bin Xu, M.D., Ph.D.. Pleomorphic adenoma. Last author update: 30 July 2021. Last staff update: 5 August 2021
  4. Image by Mikael Häggström, MD. References for entries:
    - Köybaşioğlu FF, Önal B, Han Ü, Adabağ A, Şahpaz A (2020). "Cytomorphological findings in diagnosis of Warthin tumor ". Turk J Med Sci 50 (1): 148-154. doi:10.3906/sag-1901-215. PMID 31769640. PMC: 7080357. Archived from the original. . 
    Binucleation:
    - Dr.S. Malliga (2006-10-18). A correlative cytological and histopathological study on lesions of salivary gland.
    - Chan MKM, McGuire LJ: Cytodiagnosis of Lesions Presenting as Salivary Gland Swellings: A Report of Seven Cases. Diagn Cytopathol 8: 439-443, 1992b.
  5. Adriana Handra-Luca, M.D., Ph.D., Jen-Fan Hang, M.D.. Warthin tumor. Pathology Outlines. Last author update: 1 September 2012. Last staff update: 28 June 2022

Image sources


Thyroid

Fixation

Generally 10% neutral buffered formalin. Fix all thyroids at least overnight to avoid artifactual nuclear atypia.[1]

  See also: General notes on fixation

Removal during autopsy

Parathyroid glands (white arrow), next to the thyroid gland.

Sharply dissect the thyroid from the cartilage, starting at the posterior end of each lobe & working forward. Do not cut the isthmus. Try to find parathyroids.

Gross processing of thyroidectomy

  • Weigh.[2] Up to 30 g versus over 30 g grams is an accepted cutoff between normal and increased weight of the thyroid gland.[3]
  • Measure each lobe and isthmus in 3 dimensions, respectively.[2]
  • Ink outer surface,[2] at least if malignancy is suspected.[4]

((In addition, use different ink colors on the anterior versus posterior “capsular” or "peripheral" surface.))

Serially section the specimen at 3-4mm intervals,[5] such as follows:[2]

  See also: General notes on gross processing

Papillary thyroid carcinoma

A papillary thyroid carcinoma is characterized by:

Also, it typically has nuclei with:[11]

  • Enlargement, elongation, overlapping
  • Chromatin with clearing, margination, glassy / ground glass texture
  • Nuclear membrane with irregular contour

Other thyroid tumors

Reporting

For cancers, generally include a synoptic report, such as per College of American Pathologists (CAP) protocols at cap.org/protocols-and-guidelines.

  See also: General notes on reporting


Thyroid cytology

Author: Mikael Häggström [note 1]

Adequacy

A minimum number of 6 clusters with 10 cells each has been arbitrary established to assume adequacy for a definitive diagnosis.[13] The presence of characteristic cells may still confer a definitive diagnosis, but otherwise, the report will simply state inadequate number of cells.

Risk stratification

Papillary thyroid carcinoma, with typical features shown. Pap stain.

Look at least for the following imaged features, and classify findings as per the Bethesda system:

Bethesda system
Category Description[14] Example report
I Non diagnostic/unsatisfactory
II Benign (colloid and follicular cells) Thyroid aspiration, right upper pole:
Negative for malignant cells.
Clusters of benign follicular epithelial cells and colloid. Findings are consistent with a benign hyperplastic nodule. (Bethesda category II)
III Atypia of undetermined significance (AUS) or follicular lesion of undetermined significance (FLUS) (follicular or lymphoid cells with atypical features) Thyroid aspiration, right mid pole:
Clusters of atypical follicular cells of undetermined significance (Bethesda category III).
IV Follicular nodule/suspicious follicular nodule (cell crowding, micro follicles, dispersed isolated cells, scant colloid)
V Suspicious for malignancy
VI Malignant

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. . Gross Pathology Manual By The University of Chicago Department of Pathology. Updated 2-14-19 NAC.
  2. 2.0 2.1 2.2 2.3 . Gross Pathology Manual By The University of Chicago Department of Pathology. Updated 2-14-19 NAC.
  3. Shamim, A; Monira, K; Manowara, B; Sabiha, M; Alim, A; Nurunnabi, ASM (1970). "Weight of the Human Thyroid Gland – A Postmortem Study ". Bangladesh Journal of Medical Science 9 (1): 44–48. doi:10.3329/bjms.v9i1.5230. ISSN 2076-0299. 
    - In turn citing: Langer P. Discussion about the limit between normal thyroid and goiter: mini review. Endocrine regulations. 1999 March; 33(1): 39-45.
  4. Monica Dahlgren, Janne Malina, Anna Måsbäck, Otto Ljungberg. Stora utskärningen. KVAST (Swedish Society of Pathology). Retrieved on 2019-09-26.
  5. . THYROID. Royal College of pathologists of Australia. Retrieved on 2019-12-17.
  6. Swati Satturwar, M.D., F. Zahra Aly, M.D., Ph.D.. Thyroid & parathyroid - Hyperplasia / goiter - Multinodular goiter. PathologyOutlines. Last author update: 11 June 2021. Last staff update: 18 November 2021
  7. Sheren Younes, M.D.. Thyroid & parathyroid Benign thyroid neoplasms. Follicular adenoma.. Pathology Outlines. Last author update: 1 November 2014. Last staff update: 8 March 2022
  8. Cameselle-Teijeiro JM, Eloy C, Sobrinho-Simões M (2020). "Pitfalls in Challenging Thyroid Tumors: Emphasis on Differential Diagnosis and Ancillary Biomarkers. ". Endocr Pathol 31 (3): 197-217. doi:10.1007/s12022-020-09638-x. PMID 32632840. PMC: 7395918. Archived from the original. . 
    "This article is licensed under a Creative Commons Attribution 4.0 International License"
  9. Image by Mikael Häggström, MD. Reference for findings: Rachel Jug, M.B.B.Ch., B.A.O., David Poller, M.D., Xiaoyin "Sara" Jiang, M.D.. NIFTP. Pathology Outlines. Last author update: 10 May 2018
  10. Shuanzeng (Sam) Wei, M.D., Ph.D.. Thyroid & parathyroid - Other thyroid carcinoma - Main- Oncocytic (Hürthle cell) tumors. Pathology Outlines. Last author update: 1 October 2017. Last staff update: 21 July 2021
  11. Bin Xu, M.D., Ph.D.. Thyroid & parathyroid - Papillary thyroid carcinoma - Papillary thyroid carcinoma overview. Pathology Outlines. Topic Completed: 8 January 2020. Minor changes: 28 May 2021
  12. Shuanzeng (Sam) Wei, M.D., Ph.D.. Thyroid & parathyroid - Other thyroid carcinoma - Follicular. Pathology Outlines. Last author update: 1 August 2017. Last staff update: 24 May 2022
  13. Michael, Claire W.; Pang, Yijun; Pu, Robert T.; Hasteh, Farnaz; Griffith, Kent A. (2007). "Cellular adequacy for thyroid aspirates prepared by ThinPrep: How many cells are needed? ". Diagnostic Cytopathology 35 (12): 792–797. doi:10.1002/dc.20768. ISSN 87551039. 
  14. "The bethesda system for reporting thyroid cytopathology: interpretation and guidelines in surgical treatment ". Indian Journal of Otolaryngology and Head and Neck Surgery 64 (4): 305–311. December 2012. doi:10.1007/s12070-011-0289-4. PMID 24294568. 
  15. Diagram by Mikael Häggström, MD. Source data: Arul P, Masilamani S (2015). "A correlative study of solitary thyroid nodules using the bethesda system for reporting thyroid cytopathology. ". J Cancer Res Ther 11 (3): 617-22. doi:10.4103/0973-1482.157302. PMID 26458591. Archived from the original. . 
  16. Ayana Suzuki, C.T., Andrey Bychkov, M.D., Ph.D.. Thyroid & parathyroid - Follicular neoplasm. Last author update: 21 April 2022. Last staff update: 12 May 2022
  17. Costigan DC, Shaar M, Frates MC, Alexander EK, Barletta JA, Cibas ES (2020). "Defining thyroid spherules: A benign cytomorphologic feature that mimics microfollicles. ". Cancer Cytopathol 128 (3): 171-176. doi:10.1002/cncy.22219. PMID 31856389. Archived from the original. . 
  18. Image by Mikael Häggström, MD. References for findings:
    - Ayana Suzuki, C.T., Andrey Bychkov, M.D., Ph.D.. Hürthle cell neoplasm. Pathology Outlines. Last author update: 7 May 2020. Last staff update: 12 May 2022
    - Shawky M, Sakr M (2016). "Hurthle Cell Lesion: Controversies, Challenges, and Debates. ". Indian J Surg 78 (1): 41-8. doi:10.1007/s12262-015-1381-x. PMID 27186039. PMC: 4848220. Archived from the original. . 

Image sources

  1. . 4. 2021. Archived from Sharma Avishesh Singh , Ajay Sahu the original. . 
    - "This is an Open Access article that uses a funding model which does not charge readers or their institutions for access and distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0)"

Lungs

Author: Mikael Häggström [note 1]

Basic microscopic screening

For screening of lung autopsies, see Lung autopsy

Mainly look for carcinoma. Further information: Lung tumor

If granulomas are seen, generally stain for acid-fast bacteria and fungi.

Common findings

Active searching for them is not mandatory.

Other pertinent findings

For fungi not conforming to the two main forms above, a general pathologist may attempt to get input by readily available expertise locally, but if it cannot be readily speciated, then it's generally acceptable to simply report as fungi present.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Madea, B (2014). Handbook of forensic medicine . Hoboken, N.J: Wiley-Blackwell. ISBN 978-1-118-57062-3. OCLC 872114659. 
  2. Error on call to Template:cite web: Parameters url and title must be specified. . Wellcome Collection. Retrieved on 2024-02-21. License: CC0 1.0 Universal
  3. Lee JH, Hyun JS, Kang DY, Lee HJ, Park SG (2016). "Rare complication of bronchoesophageal fistula due to pulmonary mucormycosis after induction chemotherapy for acute myeloid leukemia: a case report. ". J Med Case Rep 10: 195. doi:10.1186/s13256-016-0991-7. PMID 27423701. PMC: 4947348. Archived from the original. . 
    - "This article is distributed under the terms of the Creative Commons Attribution 4.0 International License"

Image sources


Lung tumor

Gross processing

As per presentation above.

Microscopic evaluation

Lung cancers by relative incidence.

Medical imaging provides a major clue as to whether a lung tumor is benign or malignant, where lesions smaller than 2 cm are likely to be benign, whereas lesions larger than 2 cm are malignant (that is, lung cancer) in 85% of cases.[1]

Benign tumors

Subsequently distribution of benign tumors and lung cancers, respectively, are as follows:[1]

Minute pulmonary meningothelial-like nodules (MPMNs) are interstitial nodular proliferations of small oval or spindle-shape cells in nests,[2] and do not need reporting.[image 1]

Benign lung tumors:

  • Hamartomas - 76%
  • Benign fibrous mesothelioma/solitary fibrous tumor (SFT) - 12.3%
  • Inflammatory pseudotumor (IPT) - 5.4%
  • Lipoma - 1.5%
  • Leiomyoma - 1.5%
  • Other - 3.3%

Lung cancers

TTF-1 needs to have nuclear staining on immunohistochemistry to count as positive. Cytoplasmic staining is disregarded for diagnostic purposes.[5]

Whereas large cell carcinoma is more often histologically distinct, adenocarcinoma and SCC may look alike. In such cases, an immunohistochemistry panel of TTF1, CK5/6, and p63 can be used to distinguish the two.[6][7]

Further workup

edit
For primary lung non-small cell carcinoma (NSCLC) stages IB - IV (such as being more than 3 cm in size), generally perform full next generation sequencing panel (DNA and RNA) with PDL-1 immunostaining. For an advanced stage NSCLC that is not a candidate for biopsy or re-biopsy, a viable alternative is “liquid biopsy” on peripheral blood for circulating tumor DNA.[8]

Notes


Main page

References

  1. 1.0 1.1 Alain C. Borczuk (2008). "Benign Tumors and Tumorlike Conditions of the Lung ". Archives of Pathology & Laboratory Medicine 132 (7). Archived from the original. . 
  2. Kuroki, Masaomi; Nakata, Hiroshi; Masuda, Toshifumi; Hashiguchi, Norihisa; Tamura, Shozo; Nabeshima, Kazuki; Matsuzaki, Yasunori; Onitsuka, Toshio (2002). "Minute Pulmonary Meningothelial-like Nodules: High-Resolution Computed Tomography and Pathologic Correlations ". Journal of Thoracic Imaging 17 (3): 227–229. doi:10.1097/00005382-200207000-00008. ISSN 0883-5993. 
  3. Dr Nicholas Turnbull, A/Prof Patrick Emanual (2014-05-03). Squamous cell carcinoma pathology. DermNetz.
  4. Image by Mikael Häggström, MD. Source for findings: Caroline I.M. Underwood, M.D., Carolyn Glass, M.D., Ph.D.. Lung - Small cell carcinoma. Pathology Outlines. Last author update: 20 September 2022}}
  5. Image by Mikael Häggström, MD. Source for significance: Bejarano PA, Mousavi F (2003). "Incidence and significance of cytoplasmic thyroid transcription factor-1 immunoreactivity. ". Arch Pathol Lab Med 127 (2): 193-5. doi:10.5858/2003-127-193-IASOCT. PMID 12562233. Archived from the original. . 
  6. Inamura K (2018). "Update on Immunohistochemistry for the Diagnosis of Lung Cancer. ". Cancers (Basel) 10 (3). doi:10.3390/cancers10030072. PMID 29538329. PMC: 5876647. Archived from the original. . 
  7. Affandi KA, Tizen NMS, Mustangin M, Zin RRMRM (2018). "p40 Immunohistochemistry Is an Excellent Marker in Primary Lung Squamous Cell Carcinoma. ". J Pathol Transl Med 52 (5): 283-289. doi:10.4132/jptm.2018.08.14. PMID 30235512. PMC: 6166010. Archived from the original. . 
  8. . National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines in Oncology (NCCN Guidelines) - Non-Small Cell Lung Cancer. Version 3.2024. Section: Principles of molecular and biomarker analysis (2024-03-12).

Image sources

Lung wedge resection and lobectomy

Author: Mikael Häggström [note 1]

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))
Other legend

<< Decision needed between alternatives separated by / signs >>
{{Common findings / In case of findings}}
[[Comments]]
Link to another page

Intraoperative consultation

Perform:

  • Tumor microscopy on frozen sectioning if there is intermediate risk of cancer (if frozen section does not show cancer, the surgeon may not need to perform lymph node dissection)
  • Margin assessment: A gross distance from tumor to the parenchymal is generally sufficient, unless a suspected malignancy is close enough to confer a significant risk of extension to the margin, in which case the closest parenchymal margin should be frozen en face[note 2]. For lobectomies, generally perform frozen section on the bronchial and vascular margin en face[note 2].

Grossing

Surgical margin sampling of a lobectomy for intraoperative consultation.

Perform the following:[1]

  • Measure the specimen in 3 dimensions.
  • (Weigh lobectomies.).
  • Describe pleural surface, including color, and any presence of granularity, adhesions, retraction, or tumor.
  • Palpate for any tumors.
  • Ink the surgical margin and cut it away just below any sutures or staples. If the margin is substantially stapled (and their removal would be either too tissue-damaging or otherwise inconvenient), ink and use another section of the tissue underneath it for frozen sectioning.
  • In intraoperative consultations use a section that is presumably closest to a tumor for frozen sectioning, with the tissue en face[note 2], for radicality. This is generally enough to report intraoperatively to the surgeon, unless otherwise requested.
  • ((Sample the entire surgical margin for standard processing.))
  • Cut open the bronchi of the specimen with a pair of scissors, as far as they can fit within the lumina. Attempt to cut so as to be able to take a section that includes both any tumor and nearest bronchus. Palpate for tumors intermittently. Describe the cut surface, including color and consistency, and any focal lesions.
  • Turn the specimen to the side with least cuts so far, and serially section it. Palpate for tumors intermittently.
Initial measurements when
triaging fresh lobectomies
  • Size of lobe in 3 dimenstions
  • Size of tumor (in 3 dimensions)
  • (Weight)
  • Distance from tumor to closest
    parenchymal, bronchial and vascular margins
  • Measure tumor size as a maximum diameter (or 3 dimensions)
  • Determine location: Which lobe if applicable, and if it is peripheral, central or hilar.
  • Margin length to pleura and hilum/surgical margin.
  • Any involvement of major bronchi or blood vessels.
  • Describe any lymph nodes, including location, range of sizes and appearance of cut surface.

Tissue selection

Vascular (inked yellow), bronchial (inked blue) and parenchymal (inked black) margins of a lobectomy, showing staple line of bronchial margin being removed with scissors to allow for tissue selection.
  • 1 from bronchial and vascular margins, en face[note 2], if present, ((differentially inked))
  • 1 from nearest parenchymal margin, en face
  • Sections of any tumor
  • Any other focal change
  • 1 from random non-neoplastic lung tissue

Gross report

((A. Labeled - ___. The specimen is received fresh for intraoperative consultation and consists of)) of a right upper lobe of lung which measures __ x __ x __ cm (and weighs __ g). The specimen includes a bronchial stump measuring __ cm in length and __ cm in diameter, which grossly appears unremarkable. The pleural surface is mottled tan-pink {{and slightly puckered on the __ aspect}}. There is a staple line representing the parenchymal margin measuring __ cm in length. The stapled margin is inked black. (On opening the bronchial tree, the mucosa is tan and smooth and the lumens are patent. The blood vessels are opened to reveal no blood clot or tumor.) {{Cut section show an irregular, gray-tan, rubbery firm mass measuring __ x __ x __ cm. The tumor is located __ cm from the bronchial and vascular margin and __ cm from the nearest surgical margin. The tumor abuts smaller bronchi and vessels.}} The remaining parenchyma is pink and spongy. (No lymph nodes are identified in the peribronchial region.) (Representative sections are submitted for microscopic examination in __ cassettes.)
  See also: General notes on gross processing

Microscopic evaluation

Look mainly for carcinoma. Further information: Lung tumor

Microscopy report

Lung synoptic reports contain information (number and station) on all lymph nodes received per accession. For example, if Parts A-D are mediastinal nodes (8 in total) and Part E is a lobectomy containing 2 additional peribronchial nodes, the synoptic report for Part E should document all 10 nodes, for example:

A. Lymph node, station 1:
Negative for carcinoma. (0/1, 2 etc)

B. Lymph node, station 2:
Negative for carcinoma. (0/1, 2 etc)

C. Lobectomy, RLL: Adenocarcinoma

Size:
Histologic type
Margins
  See also: General notes on reporting

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. 2.0 2.1 2.2 2.3 En face means that the section is tangential to the region of interest (such as a lesion) of a specimen. Further information: Gross_processing#Cutting

Main page

References

  1. Partially using the following procedure:. Pulmonary pathology grossing guidelines. Retrieved on 2021-03-17.

Image sources


Lymph nodes

Author: Mikael Häggström [note 1]

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Gross processing

If suspected lymphoma, before putting tissue in formalin, ensure that tissue is preserved in appropriate media for any special tests (usually flow cytometry). Further information: Lymphoma

In samples with tumors, slice through all included fat while palpating and looking for lymph nodes, and submit all that are found.

For lymph nodes taken for potential breast cancer metastasis, find out and report the procurement time and the time when put in formalin.[note 2]

Gross procedure

  • Measure the dimensions. For a lymph node with minimal surrounding fatty tissue, measure the greatest dimension (or 3 dimensions). For specimens with substantial amount of fatty tissue, measure the specimen in 3 dimensions, and measure the greatest dimension seen for individual lymph nodes therein after serial sectioning.
  • Find as many lymph nodes as you can in a specimen. Good locations to start include the presumed lymphatic drainage directions from a tumor, as well as when following the lymphatic directions from the vascular margins of a specimen. Serially section fatty tissue into slices that are thin enough to be palpated for small ovoid resistances. If you still have trouble finding enough lymph nodes, put fatty tissue in a vinegar and acetic acid solution made for the purpose of turning lymph nodes pale/white as well as making them more firm for palpation. Colon tumors are sometimes tattooed during endoscopy, and in such cases the tatoo ink often stains lymph nodes as well.
  • Section lymph nodes if needed. Lymph nodes less than 5 mm may be submitted whole, while larger lymph nodes may be sectioned at 2-3 mm intervals.[1]
  • Generally do not submit multiple sectioned lymph nodes in the same cassette, to allow exact counting of the number of involved lymph nodes on microscopy. If you will nevertheless submit multiple bisected lymph nodes in the same cassette, ink each lymph node differently.
Making a "touch prep": Press a glass slide against the cut surface of the lymph node, apply cytologic fixative solution immediately and stain with H&E.
  • If suspected lymphoma, such as an enlarged lymph node without any adjacent tumor or another almost certain cause, make a touch prep. Also, take a small fresh sample for flow cytometry:
  • For flow cytometry, aim for a tissue size of approximately 5 mm3. Put it in specific flow cytometry preservative medium (such as RPMI), and ensure it gets to the flow cytometry lab. If it is after normal hours and there is no one to ask to find such medium, you can put the specimen in normal sterile saline (enough to cover the tissue) in a fridge (2-8°C) until the next morning.[2] If you receive multiple lymph nodes for flow cytometry, still only sample one (unless the referral asks for separate flow cytometry studies, or there is a given history of one lymph node having high uptake and another having low uptake on PET scanning).

Definition of an enlarged lymph node

Long and short axis.png
  • By size, where lymphadenopathy in adults is often defined as a short axis of one or more lymph nodes is greater than 10mm.[3][4] However, there is regional variation as detailed in this table:
Upper limit of lymph node sizes in adults
Generally 10 mm[3][4]
Inguinal 10[5] – 20 mm[6]
Pelvis 10 mm for ovoid lymph nodes, 8 mm for rounded[5]
Neck
Generally (non-retropharyngeal) 10 mm[5][7]
Jugulodigastric lymph nodes 11mm[5] or 15 mm[7]
Retropharyngeal 8 mm[7]
  • Lateral retropharyngeal: 5 mm[5]
Mediastinum
Mediastinum, generally 10 mm[5]
Superior mediastinum and high paratracheal 7mm[8]
Low paratracheal and subcarinal 11 mm[8]
Upper abdominal
Retrocrural space 6 mm[9]
Paracardiac 8 mm[9]
Gastrohepatic ligament 8 mm[9]
Upper paraaortic region 9 mm[9]
Portacaval space 10 mm[9]
Porta hepatis 7 mm[9]
Lower paraaortic region 11 mm[9]

Lymphadenopathy of the axillary lymph nodes can be defined as solid nodes measuring more than 15 mm without fatty hilum.[10] Axillary lymph nodes may be normal up to 30 mm if consisting largely of fat.[10]

In children, a short axis of 8 mm can be used.[11] However, inguinal lymph nodes of up to 15 mm and cervical lymph nodes of up to 20 mm are generally normal in children up to age 8–12.[12]

Lymphadenopathy of more than 1.5 cm - 2 cm increases the risk of cancer or granulomatous disease as the cause rather than only inflammation or infection.[13]

Urgency

The processing of lymph nodes is preferably rushed when the H&E stain will determine whether immunohistochemistry will be performed, especially when a lymph node is submitted together with a separate specimen that may be solved without immunostains. This rushing allows you to have the immunostained slides by a similar time as the rest of the case.[14] Examples of cases that are preferably rushed for such reasons include those that may be stained by CK AE1/AE3 in order to visualize otherwise occult lymph node involvement if you don't see any involvement on the H&E stain, mainly in cases when one or more sentinel lymph nodes are submitted together with any of the following:

Rushing is not necessary for non-sentinel lymph nodes.

Gross report

Individual lymph node, example
((A. Labeled - ___. The specimen is received in formalin and consists of)) __ fragment(s) of soft pink-tan tissue, measuring __ cm in greatest dimension (or __ x __ x __(. (Representative sections are submitted for microscopic examination in __ cassettes.)
Multiple lymph nodes
((A. Labeled - ___. The specimen is received fresh and consists of)) 2 irregular fragments of yellow-tan fatty and fibrous soft tissue measuring __ and ___ cm in greatest dimension. Within the adipose tissue are multiple tan-brown lymph nodes measuring up to __ cm in greatest dimension. The cut surfaces display no gross lesions. The lymph nodes are entirely submitted for microscopic examination (in 10 cassettes).
KEY TO SECTIONS:
  • A1–A3– one lymph node, serially section
  • A4-A5– one lymph node, serially sectioned
  • A6– one lymph node, bisected
  • A7– one lymph node, bisected
  • A8– two lymph nodes, each bisected, differentially inked
  • A9– one lymph node, bisected
  • A10– multiple lymph nodes.
Additional information
  • If potential breast cancer metastasis: The specimen was procured at __ AM/PM on (date), 2020. The specimen was placed in formalin at __ AM/PM on (date), 2020.
  • If lymphoma workup: A touch prep is made, and a minor part of the specimen is submitted for flow cytometry. The remainder of the specimen is submitted for microscopic examination in one cassette.

Microscopic examination

Defining a lymph node

For counting lymph nodes, each should have a discernible capsule around lymphoid cells. Also count larger free-standing lymphoid aggregates. However, the definition of what constitutes a lymph node is largely subjective.[15] Also strive to keep a consistency with the gross description. In addition, any cancer involvement is in itself a relative indication of being a lymph node.

General screening

Look for:

  • Whatever pathology is indicated by the referral, or findings in other submitted specimens.
  • Enlargement, as preferably measured during grossing, but can possibly be made on the microscopy slide. If present, see separate section below.

Microscopy of enlarged lymph nodes

Look at any other slides for the same case first, in order to find any pathology that may be reflected in in the lymph nodes as well, mainly cancer metastasis or reactive lymph nodes from inflammation.

Look primarily at the overall architecture, with main findings being:

  • Paracortical hyperplasia: Paracortical hyperplasia of a reactive lymph node shows expansion of paracortical areas by a mixed infiltrate, often having a mottled appearance, and it usually has a concomitant reactive follicular hyperplasia.[17] A T-cell lymphoma should be suspected if there is obliteration or marked diminution of the B-cell cortical region, or highly irregular or hyperchromatic nuclei.[17]
  • Unspecific hyperplasia: An unspecific pattern of lymph node enlargement, without atypical cells, in the lymphatic drainage direction from an inflamed area, may simply be diagnosed as "benign reactive lymph node".

Workup of cancerous lymph nodes

If cancer is detected in a lymph node:

  • Attempt to specify a specific cancer diagnosis'. If the patient has a known carcinoma or sarcoma etc, it is generally enough to confirm that it is consistent with a metastasis thereof.
  • Measure the size of involvement.
  • Look for extranodal extension.

Reporting

A non-involved lymph node in a patient with cancer can be reported for example as:

Sentinel lymph node #1, left axilla, (excision):
One benign lymph node((, negative for malignancy (0/1))).

Cancerous lymph nodes with patients with known consistent cancer primary can be reported as metastatic,, such as:

Sentinel lymph node #2, left axilla, (excision):
Macrometastatic carcinoma involving one of one (1/1) lymph node.
Metastatic carcinoma measures 0.4 cm in greatest dimension.
(Negative for extranodal extension).

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. The duration that a specimen has been without formalin affects mainly the reliability of estreogen and progesteron receptor testing:
    - Pekmezci, Melike; Szpaderska, Anna; Osipo, Clodia; Erşahin, Çağatay (2012). "The Effect of Cold Ischemia Time and/or Formalin Fixation on Estrogen Receptor, Progesterone Receptor, and Human Epidermal Growth Factor Receptor-2 Results in Breast Carcinoma ". Pathology Research International 2012: 1–7. doi:10.1155/2012/947041. ISSN 2090-8091. 

Main page

References

  1. . Protocol for the Examination of Biopsy Specimens From Patients With Melanoma of the Skin. College of American Pathologists. Version: Melanoma Biopsy 4.1.0.0 Protocol Posting Date: August 2019
  2. . Specimen Information and Requirements for Flow Cytometry Testing. Lifelabs. Doc #8218 Ver: 7.0 Current Issued: 13-Apr-2018
  3. 3.0 3.1 Ganeshalingam, Skandadas; Koh, Dow-Mu (2009). "Nodal staging ". Cancer Imaging 9 (1): 104–111. doi:10.1102/1470-7330.2009.0017. ISSN 1470-7330. PMID 20080453. 
  4. 4.0 4.1 Schmidt Júnior, Aurelino Fernandes; Rodrigues, Olavo Ribeiro; Matheus, Roberto Storte; Kim, Jorge Du Ub; Jatene, Fábio Biscegli (2007). "Distribuição, tamanho e número dos linfonodos mediastinais: definições por meio de estudo anatômico ". Jornal Brasileiro de Pneumologia 33 (2): 134–140. doi:10.1590/S1806-37132007000200006. ISSN 1806-3713. PMID 17724531. 
  5. 5.0 5.1 5.2 5.3 5.4 5.5 "Current concepts in lymph node imaging ". Journal of Nuclear Medicine 45 (9): 1509–18. September 2004. PMID 15347718. 
  6. . Assessment of lymphadenopathy. BMJ Best Practice. Retrieved on 2017-03-04. Last updated: Last updated: Feb 16, 2017
  7. 7.0 7.1 7.2 Page 432 in: Luca Saba (2016). Image Principles, Neck, and the Brain . CRC Press. ISBN 9781482216202. 
  8. 8.0 8.1 Sharma, Amita; Fidias, Panos; Hayman, L. Anne; Loomis, Susanne L.; Taber, Katherine H.; Aquino, Suzanne L. (2004). "Patterns of Lymphadenopathy in Thoracic Malignancies ". RadioGraphics 24 (2): 419–434. doi:10.1148/rg.242035075. ISSN 0271-5333. PMID 15026591. Archived from the original. . 
  9. 9.0 9.1 9.2 9.3 9.4 9.5 9.6 Dorfman, R E; Alpern, M B; Gross, B H; Sandler, M A (1991). "Upper abdominal lymph nodes: criteria for normal size determined with CT. ". Radiology 180 (2): 319–322. doi:10.1148/radiology.180.2.2068292. ISSN 0033-8419. PMID 2068292. 
  10. 10.0 10.1 Page 559 in: Wolfgang Dähnert (2011). Radiology Review Manual . Lippincott Williams & Wilkins. ISBN 9781609139438. 
  11. Page 942 in: Richard M. Gore, Marc S. Levine (2010). High Yield Imaging Gastrointestinal HIGH YIELD in Radiology . Elsevier Health Sciences. ISBN 9781455711444. 
  12. Laurence Knott. Generalised Lymphadenopathy. Patient UK. Retrieved on 2017-03-04. Last checked: 24 March 2014
  13. "Lymphadenopathy and malignancy ". American Family Physician 66 (11): 2103–10. December 2002. PMID 12484692. 
  14. Chandler IP, Oommen R, Lawson CW (2003). "Invasive lobular carcinoma and cytokeratin immunohistochemistry: an audit. ". J Clin Pathol 56 (3): 240. doi:10.1136/jcp.56.3.240. PMID 12610108. PMC: 1769908. Archived from the original. . 
  15. Parkash V, Bifulco C, Feinn R, Concato J, Jain D (2010). "To count and how to count, that is the question: interobserver and intraobserver variability among pathologists in lymph node counting. ". Am J Clin Pathol 134 (1): 42-9. doi:10.1309/AJCPO92DZMUCGEUF. PMID 20551265. Archived from the original. . 
  16. Egan, Caoimhe; Jaffe, Elaine S. (2018). "Non-neoplastic histiocytic and dendritic cell disorders in lymph nodes ". Seminars in Diagnostic Pathology 35 (1): 20–33. doi:10.1053/j.semdp.2017.11.002. ISSN 07402570. 
  17. 17.0 17.1 Weiss, Lawrence M; O'Malley, Dennis (2013). "Benign lymphadenopathies ". Modern Pathology 26 (S1): S88–S96. doi:10.1038/modpathol.2012.176. ISSN 0893-3952. 

Image sources


Liver

Author: Mikael Häggström [note 1]

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Tissue sampling

Fixation

Generally 10% neutral buffered formalin. Non–formalin-fixed tissue may be needed for tests such as microbiological analysis or copper quantification studies.[1]

Gross processing in autopsy

  • ((Measure the distance from the liver edge to the right costal margin.))
  • Inspect the color and texture of the surfaces, including external and cut surfaces. Potential pathologies:
  • Look for any focal change in the liver volume, mainly any tumor. If found: Further information: Liver tumor
  • Determine liver weight. The standard reference range for men is 970–1,860 g (2.14–4.10 lb)[2] and for women 600–1,770 g (1.32–3.90 lb).[3]
  • Make consecutive liver slices, such as in the sagittal or coronal plane.

Gross report in autopsy

  • ((Distance from the liver edge to the right costal margin.))
  • Weight. If abnormally low or high, preferably include the reference range.
  • Color and texture of cut surfaces
  • Any focal change

Example:

Minimal More comprehensive Normal ranges
The liver weighs ___g. The liver is << of normal size / {{enlarged}}, at ___g. [[Men: 970-1860 g.[2] Women 600-1770g.[3].]]

The liver surface is <<smooth ((and glistening)) {{/deformed by small and large nodules}}((, and is <<light tan / dark brown>> in color)). << Normal/ {{/ firm}} consistency. Cut surface[note 2] is normal / << (shows normal homogeneous brown parenchyma) / {{Yellowish color, indicating steatosis}} / {{dark nutmeg similar paths, indicating congestion}}. (No focal changes.)((The liver edge is _cm below the right costal margin.))

Microscopic evaluation

Pathologies can be topographically classified by liver zones. P: portal tract. V: central vein.

A general screening includes (with further information in sections below):

  • Looking at the referral/requisition form (and looking at the medical records) for particular conditions to look for or evaluate. (Perform a severity grading of previously known liver diseases.)
  • Commonly, this includes to quantify any cirrhosis, at least if the patient had alcohol abuse.
  • Steatosis is also common.
  • Signs of acute liver failure.
  • Signs of malignancy. If a tumor is found: Further information: Liver tumor
  • Signs of congestive hepatopathy (indicating heart failure).
  • Signs of inflammation at least around the portal triads.

Cirrhosis

Further information: Cirrhosis

Steatosis

At least classify steatosis by severity:

Steatosis grading: a: none. b: mild. c: moderate. d: severe.

Signs of acute liver failure

Congestive hepatopathy

Histopathology of congestive hepatopathy, with sinusoidal dilation in zone 3. As the severity of the lesion increases, the sinusoids around the central vein become distended with extravasated red cells and there is adjacent hepatocyte plate atrophy.[6]
  • Acute hepatic congestion shows dilated sinusoidal capillaries predominantly in zone 3 of the hepatic acinus.[7]
  • Typical findings of chronic hepatic congestion are atrophy of hepatocytes in zone 3, perisinusoidal edema, thrombosis and hemorrhage. Chronic congestion typically displays perivenous and perisinusoidal fibrosis, with fibrous septa that bridge central hepatic veins. In contrast, other causes of distortion and cirrhosis typically have fibrous septa predominantly between portal triads. However, nonalcoholic steatohepatitis also may show perisinusoidal fibrosis in early stages; in later stages, the fibrosis tends to be in the portal triad. Cirrhosis develops in the final stages of congestive hepatopathy. Regenerating hepatocytes tend to grow in a sleevelike pattern along portal tracts, resulting in a nodular liver with preserved portal triads and obliterated or fibrosed hepatic veins, a pattern called "reverse lobulation". This pattern can also be seen in venous obstruction due to Budd-Chiari syndrome.[8]

Hemosiderin

Report

  • Presence of any liver disease
  • (Quantification of its severity.)
  • ((Even absence of hepatitis, malignancy, congestive hepatopathy and/or steatosis.))

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. "Cut surface shows..." may alternatively be expressed as "On sectioning, the parenchyma is..."

Main page

References

  1. 1.0 1.1 1.2 1.3 Boyd, Alexander; Cain, Owen; Chauhan, Abhishek; Webb, Gwilym James (2020). "Medical liver biopsy: background, indications, procedure and histopathology ". Frontline Gastroenterology 11 (1): 40–47. doi:10.1136/flgastro-2018-101139. ISSN 2041-4137. 
    • "This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0) license"
  2. 2.0 2.1 Standard reference range: Molina, D. Kimberley; DiMaio, Vincent J.M. (2012). "Normal Organ Weights in Men ". The American Journal of Forensic Medicine and Pathology 33 (4): 368–372. doi:10.1097/PAF.0b013e31823d29ad. ISSN 0195-7910. 
  3. 3.0 3.1 Standard reference range: Molina, D. Kimberley; DiMaio, Vincent J. M. (2015). "Normal Organ Weights in Women ". The American Journal of Forensic Medicine and Pathology 36 (3): 182–187. doi:10.1097/PAF.0000000000000175. ISSN 0195-7910. 
  4. Ciobanu AO, Gherasim L (2018). "Ischemic Hepatitis - Intercorrelated Pathology. ". Maedica (Bucur) 13 (1): 5-11. PMID 29868133. PMC: 5972787. Archived from the original. . 
  5. Xue, Ran; Zhu, Yueke; Liu, Hui; Meng, Qinghua (2019). "The clinical parameters for the diagnosis of hepatitis B virus related acute-on-chronic liver failure with sepsis ". Scientific Reports 9 (1). doi:10.1038/s41598-019-38866-3. ISSN 2045-2322. 
    -"This article is licensed under a Creative Commons Attribution 4.0 International License"
  6. Shah, Shailja C.; Sass, David A. (2015). "“Cardiac Hepatopathy”: A Review of Liver Dysfunction in Heart Failure ". Liver Research - Open Journal 1 (1): 1–10. doi:10.17140/LROJ-1-101. ISSN 23794038. 
    -"This is an open access article distributed under the Creative Commons Attribution 4.0 International License (CC BY 4.0),"
  7. . Acute Hepatic Congestion. Pathway Medicine. Retrieved on 2020-03-06.
  8. Wells, Michael L.; Fenstad, Eric R.; Poterucha, Joseph T.; Hough, David M.; Young, Phillip M.; Araoz, Philip A.; Ehman, Richard L.; Venkatesh, Sudhakar K. (2016). "Imaging Findings of Congestive Hepatopathy ". RadioGraphics 36 (4): 1024–1037. doi:10.1148/rg.2016150207. ISSN 0271-5333. 
  9. . The Internet Pathology Laboratory for Medical Education. The University of Utah Eccles Health Sciences Library. Retrieved on 2020-12-18.

Image sources


Liver tumor

Author: Mikael Häggström [note 1]

Tissue sampling

  • Liver biopsy
  • Autopsy: Further information: Autopsy

Gross examination

Note the following:[1]

  • Whether the tumor is sell demarcated from surrounding tissue
  • Whether there is visible infiltration or invasion into surrounding tissue
  • Any necrosis or bleeding

Microscopic evaluation

A bile duct hamartoma is also very common.[2] This image shows typical features:[3]
- Small to medium sized, irregularly shaped bile ducts lined by bland cuboidal epithelium (may also be flattened).
- Prominent intervening collagenous stroma.
- Bile ducts containing eosinophilic debris (may also contain inspissated bile)

Further information: Evaluation of suspected malignancies

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. . General oncology. Amboss. Retrieved on 2020-01-29.
  2. Yang, Xiao-Yu; Zhang, Hai-Bo; Wu, Bin; Li, Ai-Jun; Fu, Xiao-Hui (2017). "Surgery is the preferred treatment for bile duct hamartomas ". Molecular and Clinical Oncology 7 (4): 649–653. doi:10.3892/mco.2017.1354. ISSN 2049-9450. 
  3. Upasana Joneja, M.D.. Liver & intrahepatic bile ducts - Developmental anomalies / cysts - Von Meyenburg complex. Pathology Outlines. Topic Completed: 23 November 2020. Minor changes: 23 November 2020
  4. Table 37.2 in: Sternberg, Stephen (2012). Sternberg's diagnostic surgical pathology . Place of publication not identified: LWW. ISBN 978-1-4511-5289-0. OCLC 953861627. 
  5. Figure 7 from Bioulac-Sage, Paulette; Sempoux, Christine; Possenti, Laurent; Frulio, Nora; Laumonier, Hervé; Laurent, Christophe; Chiche, Laurence; Frédéric Blanc, Jean; et al. (2013). "Pathological Diagnosis of Hepatocellular Cellular Adenoma according to the Clinical Context ". International Journal of Hepatology 2013: 1–13. doi:10.1155/2013/253261. ISSN 2090-3448. 
    - Attribution 3.0 Unported (CC BY 3.0) license

Image sources


Adrenals

Author: Mikael Häggström [note 1]

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Main targets

Autopsy

Autopsy processing

In autopsy:

  • Make a couple of cuts through the adrenal glands, such as transversal ones, and look mainly for adrenal tumors.
  • ((Remove the adrenals, trim them from excessive adherent fat, and weight them. Their combined weight in an adult human ranges from 7 to 10 grams.[1]))

Autopsy report

Normal status can be described as either:

  • Adrenal glands are normal bilaterally.
  • (Adrenal glands are ordinarily configured and with no definable focal changes on cut surfaces.)
  • ((The adrenals are normal in size, shape and consistency, with a weight of __ grams on the right and __ grams on the left. The cortices are orange with <normal / increased / decreased thickness>. The medullae are <grey / autolyzed>.))

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. O'Hare, A. Munro Neville, Michael J. (1982). The Human Adrenal Cortex Pathology and Biology – An Integrated Approach . Springer London. pp. Chapter 4: Structure of the adult cortex. ISBN 9781447113171. 
  2. Page 120 in: Rutty, Guy (2001). Essentials of autopsy practice . London New York: Springer. ISBN 978-1-85233-541-0. OCLC 44769560. 

Image sources


Adrenal tumors

Incidences and prognoses of adrenal tumors.[1]

Adenoma versus carcinoma

The most common adrenal tumors are adrenocortical adenomas and carcinomas. These are most commonly distinguished by the Weiss system,[2] as follows:[3]

Characteristic[3] Score
High nuclear grade (enlarged, oval to lobated, with coarsely granular to hyperchromatic chromatin and easily discernible, prominent nucleoli)[4] 1
More mitoses than 5/50 high power fields 1
Atypical mitoses 1
Eosinophilic cytoplasm in >75% of tumor cells 1
Diffuse architecture of >33% of tumor 1
Necrosis 1
Venous invasion 1
Sinusoidal invasion (no smooth muscle in wall) 1
Capsular invasion 1

Total score indicates:[3]

  • 0-2: Adrenocortical adenoma
  • 3: Undetermined
  • 4-9: Adrenocortical carcinoma

Other adrenal tumors

Reporting

For cancers, generally include a synoptic report, such as per College of American Pathologists (CAP) protocols at cap.org/protocols-and-guidelines.

Kidney with tumor

{{Renal tumor - entire article}

Urinary tract stone

Author: Mikael Häggström [note 1]
When sent to the pathology department, these are generally sent for stone analysis to determine the chemical composition.

Gross processing

Abide by local practices for what container to use and where to leave stone specimens. Generally submit the entire specimen, or as much as you can conveniently fit in the container.

Example report:

The specimen is received dry and consists of __ irregular fragment(s) of {{tan}} calculus measuring up to __ cm in maximum dimension. The entire specimen is submitted for spectrographic analysis.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Data and references for pie chart are located at file description page in Wikimedia Commons.
  2. Wang, Cuiping; Sun, Yang; Wu, Huanwen; Zhao, Dachun; Chen, Jie (2014). "Distinguishing adrenal cortical carcinomas and adenomas: a study of clinicopathological features and biomarkers ". Histopathology 64 (4): 567–576. doi:10.1111/his.12283. ISSN 03090167. 
  3. 3.0 3.1 3.2 Aye, Than Than; Myint, Phone; Myint, Kyar Nyo Soe (2015). "Adrenocortical Oncocytoma Presenting with Gynaecomastia ". Journal of the ASEAN Federation of Endocrine Societies 30 (1): 27–30. doi:10.15605/jafes.030.01.08. ISSN 08571074. 
  4. Tito Fojo. Adrenocortical Cancer. Retrieved on 2020-07-02.
  5. 5.0 5.1 Gupta S, Melendez J, Khanna A (2010). "Deoxycorticosterone producing tumor as a cause of resistant hypertension. ". Case Rep Med 2010: 372719. doi:10.1155/2010/372719. PMID 20671982. PMC: 2909735. Archived from the original. . 
    - "This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited."

Image sources

Pancreas

Author: Mikael Häggström [note 1]

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))
Upper limits of pancreas weight[1][notes 1]
Patient age Men Women
<20 years 115g 80g
21-30 years 115g 125g
31-40 years 155g 140g
41-50 years 155g 110g
51-60 years 175g 125g
>60 years 160g 110g
Overall 160g 120g

In autopsy

Inspect the pancreas regarding color and consistency. ((Separate it and measure its dimensions.))

Cut it in consecutive short axis slices.[notes 2] Note the appearance of the parenchyma (and the size of the duct).

Microscopic examination

Look for pancreatic intraepithelial neoplasia and pancreatic tumors.

Notes

  1. Upper limit is calculated as mean plus 2 standard deviations.
  2. The pancreas may also be cut in the longitudinal plane.
  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Kin, Tatsuya; Murdoch, Travis B.; Shapiro, A. M. James; Lakey, Jonathan R. T. (2017). "Estimation of Pancreas Weight from Donor Variables ". Cell Transplantation 15 (2): 181–185. doi:10.3727/000000006783982133. ISSN 0963-6897. 
  2. Hackeng WM, Hruban RH, Offerhaus GJ, Brosens LA (2016). "Surgical and molecular pathology of pancreatic neoplasms. ". Diagn Pathol 11 (1): 47. doi:10.1186/s13000-016-0497-z. PMID 27267993. PMC: 4897815. Archived from the original. . 
    - "This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/)"
    - Image title and optimization: Mikael Häggström, M.D.

Image sources


Pancreatic tumor

Microscopic evaluation

If a biopsy has been processed both for histology and cytology, make sure that their results are not contradictory.

Cancer type Relative incidence[3] Microscopy findings[3] Micrograph
Pancreatic ductal adenocarcinoma (PDAC) 90% Glands and desmoplasia Histopathology of pancreatic ductal adenocarcinoma.jpg
Pancreatic acinar cell carcinoma (ACC) 1% to 2% Granular appearance Histopathology of acinar cell carcinoma of the pancreas.jpg
Solid pseudopapillary tumor Discohesive tumor nests surrounded by thin fibrous bands. Histopathology of solid pseudopapillary tumor.png
Low and high magnification[4]
Adenosquamous carcinoma 1% to 4%[5] epithelial cells. Histopathology of adenosquamous carcinoma of the pancreas.jpg
Pancreatic neuroendocrine tumor 5% Multiple nests of tumor cells
Gastrinoma.jpg
Gastrinoma
Pre-cancer below for comparison:
Precancer:
Intraductal papillary mucinous neoplasm (IPMN)
3% Mucinous epithelial cells.[6] Growth within the pancreatic ducts.[7] Histopathology of pancreatobiliary intraductal papillary mucinous neoplasm in the pancreas.jpg

Staging

edit
Stage pancreatic cancers as follows:[8]

Tumor (T) Criteria
TX The primary tumor cannot be evaluated.
T0 No evidence of cancer was found in the pancreas.
Tis Carcinoma in situ. This includes:
  • High-grade pancreatic intraepithelial neoplasia (PanIn-3)
  • Intraductal papillary mucinous neoplasm with high-grade dysplasia
  • Intraductal tubulopapillary neoplasm with high-grade dysplasia
  • Mucinous cystic neoplasm with high-grade dysplasia.
T1 The tumor is in the pancreas only, and is ≤2 cm in greatest dimension
- T1a Tumor ≤0.5 cm in greatest dimension
- T1b Tumor >0.5 cm and <1 cm in greatest dimension
- T1c Tumor 1–2 cm in greatest dimension
T2 The tumor is in the pancreas only, and it is >2 cm and ≤4 cm in greatest dimension
T3 Tumor >4 cm in greatest dimension
T4 Tumor involves celiac axis, superior mesenteric artery, and/or common hepatic artery, regardless of size
Node (N) Criteria
NX The regional lymph nodes cannot be evaluated.
N0 Cancer was not found in the regional lymph nodes.
N1 Metastasis in 1 to 3 regional lymph nodes.
N2 Metastasis in 4 or more regional lymph nodes.
Metastasis (M) Criteria
M0 No distant metastasis
M1 Distant metastasis, including distant lymph nodes. Pancreatic cancer most commonly spreads to the liver, the peritoneum, and the lungs.


Cornea

Author: Mikael Häggström [note 1]

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))

Gross processing

  • Inspect
  • Measure
  • Serially section in 3-4 mm wide slices.

Example gross report:

(Labeled: ___. The specimen is received in formalin and consists of an) << opaque / translucent>> corneal disc measuring __ cm in diameter and __ cm in thickness. The specimen is serially sectioned and entirely submitted for microscopic examination in one cassette.

Microscopic examination

Corneal subepithelial acute inflammation, seen as the presence of neutrophils, as well as chronic inflammation, seen as plasma cells and lymphocytes. There is an associated neovascularization. Bowman's membrane is disrupted. The findings are non-specific.

Look for integrity of Bowman's and Descemet's membranes.

For corneal opacities, look for the most common causes, which generally manifest as:[9]

  • Inflammation and edema
  • Traumatic injury

Reporting

Example:

Histopathology of corneal acute and chronic inflammation.jpg

(Right eye cornea, excision:
Cornea with)
patchy acute and chronic inflammation, nonspecific, with disrupted Bowman's membrane and associated neovascularization.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Hackeng WM, Hruban RH, Offerhaus GJ, Brosens LA (2016). "Surgical and molecular pathology of pancreatic neoplasms. ". Diagn Pathol 11 (1): 47. doi:10.1186/s13000-016-0497-z. PMID 27267993. PMC: 4897815. Archived from the original. . 
    - "This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/)"
    - Image title and optimization: Mikael Häggström, M.D.
  2. Diagram by Mikael Häggström, M.D.
    Source data: Wang Y, Miller FH, Chen ZE, Merrick L, Mortele KJ, Hoff FL (2011). "Diffusion-weighted MR imaging of solid and cystic lesions of the pancreas. ". Radiographics 31 (3): E47-64. doi:10.1148/rg.313105174. PMID 21721197. Archived from the original. . 
  3. 3.0 3.1 Unless otherwise specified in boxes, reference is: "Therapeutic Implications of Molecular Subtyping for Pancreatic Cancer ". Oncology 31 (3): 159–66, 168. March 2017. PMID 28299752. Archived from the original. . 
  4. Image by Mikael Häggström, MD.
    Reference for features: Pooja Navale, M.D., Omid Savari, M.D., Joseph F. Tomashefski, Jr., M.D., Monika Vyas, M.D.. Solid pseudopapillary neoplasm. Last author update: 4 March 2022
  5. "Adenosquamous carcinoma of the pancreas: a case report ". Cases Journal 3 (1): 41. February 2010. doi:10.1186/1757-1626-3-41. PMID 20205828. 
  6. Diana Agostini-Vulaj. Pancreas – Exocrine tumors / carcinomas – Intraductal papillary mucinous neoplasm (IPMN). Pathology Outlines. Topic Completed: 1 July 2018. Revised: 9 March 2020
  7. "Pathologic Evaluation and Reporting of Intraductal Papillary Mucinous Neoplasms of the Pancreas and Other Tumoral Intraepithelial Neoplasms of Pancreatobiliary Tract: Recommendations of Verona Consensus Meeting ". Annals of Surgery 263 (1): 162–77. January 2016. doi:10.1097/SLA.0000000000001173. PMID 25775066. 
  8. Amin, Mahul (2017). AJCC cancer staging manual (8 ed.). Switzerland: Springer. ISBN 978-3-319-40617-6. OCLC 961218414. 
    - For access, see the Secrets chapter of Patholines.
    - Copyright note: The AJCC, 8th Ed. is published by a company in Switzerland, and the tables presented therein are Public Domain because they consist of tabular information without literary or artistic innovation, and therefore do not fulfil the inclusion criterion of the Swiss Copyright Act (CopA) which applies to "literary and artistic intellectual creations with individual character" (see Federal Act on Copyright and Related Rights (Copyright Act, CopA) of 9 October 1992 (Status as of 1 January 2022)). edit
  9. Michael Woods (2018). Corneal Opacity. Winchester Hospital, MA.

Image sources


Nasal cavity

  1. REDIRECT Nasal cavity and paranasal sinuses

Parathyroid glands

Author: Mikael Häggström [note 1]

Presentations

Intraoperative consultation

Necessary components are:

  • Weight of the parathyroid gland or fragment thereof. Generally, there should not be any subjective description of "enlarged" or similar.[note 2]
  • Presence of parathyroid tissue upon frozen section. In particular, exclude sampling from the thyroid. It is not necessary to specify any particular parathyroid pathology on intraoperative consultation (which in case of hyperparathyroidism relies on imaging and intraoperative parathyroid hormone levels rather than the histopathology)[1].

Autopsy

Optionally for a comprehensive autopsy, or where there is suspicion of parathyroid pathology, an effort is made to find the parathyroid glands, and inspect them for general or focal hyper-/neoplasia.

Microscopic evaluation

The main conditions to look for and distinguish are:

  • Parathyroid hyperplasia: Typically involves all 4 glands with diffuse enlargement.[2]
  • Parathyroid adenoma: Typically nodular growth with compressed rim of normal tissue.[2]

Either is indicated by a decreased amount of intra-gland adipose tissue, and increased weight. A weight of 35-160 mg is above average but not in itself "enlarged" in the absence of other findings.[note 2]

Microscopy report

Example for an intraoperative consultation:

A. Left inferior parathyroid, excision:
24 mg of parathyroid tissue.

C. Right superior parathyroid, excision:
14 mg of parathyroid tissue.

Whenever possible, make a single report for multiple fragments from the same location. Example of final report, including additional fragments from the same locations:

A,B. Left inferior parathyroid gland, excision:
Hypercellular parathyroid gland (121 mg aggregate weight), consistent with parathyroid hyperplasia.

C,D. Right superior parathyroid gland, excision:
Parathyroid gland (94 mg aggregate weight) without significant histopathologic changes.

E. Left superior parathyroid gland, excision:
Hypercellular parathyroid gland (142 mg aggregate weight), consistent with parathyroid hyperplasia.

F. Right inferior parathyroid gland, excision:
Hypercellular parathyroid gland (85 mg aggregate weight), consistent with parathyroid hyperplasia.

Normal example in autopsy:

Sections show <<1, 2, 3, 4>> parathyroid glands with no focal changes or signs of hyperplasia.


Urinary bladder

Author: Mikael Häggström [note 1]

Urinary bladder biopsy

Usually performed as a transuretral resection of the bladder (TURB).

Gross reporting of transurethral resections

  • Generally submit all material. (It may be sufficient to submit representative sections that include the muscular layer, if grossly identified. Yet, many departments require submission of the entire specimen regardless, so if unsure, that is the safe choice.)
  • If transported or processed together with other cases, put the samples in thin-mesh cassettes or tissue bags to limit contamination.[note 3]

Example report:

Container A. Labeled "bladder tumor". The specimen is received in formalin and consists of multiple fragments of tan-gray, friable soft tissue measuring about __ x __ x __ cm in aggregate. The specimen is entirely submitted for microscopic examination in __ cassettes.

Microscopy

Mainly look for urothelial carcinoma (also called transitional cell carcinoma), which constitutes 95% of bladder cancers.[4]

Other possibilities:

Notes

  1. 1.0 1.1 For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. 2.0 2.1 The average weight of each parathyroid gland is about 30 mg in men and 35 mg in women,A but with a great variability: 90% of normal parathyroid glands weight less than 100g, and 96% less than 160g.B Thus, by weight alone, a pathologists generally can't tell whether a parathyroid is enlarged, or whether it is of its normal weight, such as being one of the 4% that are normally over 160g.
    - A. Johnson, S J (1 April 2005). "Best Practice No 183: Examination of parathyroid gland specimens ". Journal of Clinical Pathology 58 (4): 338–342. doi:10.1136/jcp.2002.002550. PMID 15790694. 
    - B. Yao, Kathy; Singer, Frederick R.; Roth, Sanford I.; Sassoon, Aaron; Ye, Cynthia; Giuliano, Armando E. (2004). "Weight of Normal Parathyroid Glands in Patients with Parathyroid Adenomas ". The Journal of Clinical Endocrinology & Metabolism 89 (7): 3208–3213. doi:10.1210/jc.2003-031184. ISSN 0021-972X. 
  3. Urothelial carcinoma is a promiscuous contaminant of other tissues.
    - Carll T, Fuja C, Antic T, Lastra R, Pytel P (2022). "Tissue Contamination During Transportation of Formalin-Fixed, Paraffin-Embedded Blocks. ". Am J Clin Pathol 158 (1): 96-104. doi:10.1093/ajcp/aqac014. PMID 35195717. Archived from the original. . 

Main page

References

  1. Naik AH, Wani MA, Wani KA, Laway BA, Malik AA, Shah ZA (2018). "Intraoperative Parathyroid Hormone Monitoring in Guiding Adequate Parathyroidectomy. ". Indian J Endocrinol Metab 22 (3): 410-416. doi:10.4103/ijem.IJEM_678_17. PMID 30090736. PMC: 6063190. Archived from the original. . 
  2. 2.0 2.1 Diana Murro Lin. Thyroid & parathyroid - Parathyroid nonmalignant - Parathyroid adenoma. Pathology Outlines. Topic Completed: 27 October 2020. Minor changes: 2 June 2021.
  3. Piciucchi, Sara; Barone, Domenico; Gavelli, Giampaolo; Dubini, Alessandra; Oboldi, Devil; Matteuci, Federica (2012). "Primary Hyperparathyroidism: Imaging to Pathology ". Journal of Clinical Imaging Science 2: 59. doi:10.4103/2156-7514.102053. ISSN 2156-7514. 
    - This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
  4. . Types of Bladder Cancer: TCC & Other Variants. CTCA.
  5. Monika Roychowdhury. Bladder, ureter & renal pelvis - Urothelial neoplasms - noninvasive - Inverted urothelial papilloma. Pathology Outlines. Topic Completed: 1 December 2014. Minor changes: 3 December 2020

Image sources


Urine cytology

Author: Mikael Häggström [note 1]

Normal urothelial cells.

Clinical information

It is not necessary to look through more than readily available reports from previous urine cytologies.

Evaluation

Mainly look for:

The Paris System for reporting urine cytology, version 2.0.[2]

The N/C ratios apply to the finding of any cells meeting the criteria, and not the average among atypical cells (in the majority of obviously positive cases, N/C/ratio averages 0.5).[2] When there are obvious features of malignancy, there is no need to hunt for cells that fulfil all criteria to make such diagnosis.[2]

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Wang Y, Auger M, Kanber Y, Caglar D, Brimo F (2018). "Implementing The Paris System for Reporting Urinary Cytology results in a decrease in the rate of the "atypical" category and an increase in its prediction of subsequent high-grade urothelial carcinoma. ". Cancer Cytopathol 126 (3): 207-214. doi:10.1002/cncy.21958. PMID 29278461. Archived from the original. . 
  2. 2.0 2.1 2.2 - Image by Mikael Häggström. Reference: Wojcik EM, Kurtycz DFI, Rosenthal DL (2022). "We'll always have Paris The Paris System for Reporting Urinary Cytology 2022. ". J Am Soc Cytopathol 11 (2): 62-66. doi:10.1016/j.jasc.2021.12.003. PMID 35094954. Archived from the original. . 

Image sources


Digit

Author: Mikael Häggström [note 1]
For an amputated toe or finger:

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))
Other legend

<< Decision needed between alternatives separated by / signs >>
{{Common findings / In case of findings}}
[[Comments]]
Link to another page

Intitial processing

  • Measure length and average diameter
  • Determine the anatomic location of the cut (proximal to the distal phalanx, middle phalanx, metatarsal phalangeal joint etc).
  • Look at soft tissue margins whether they look viable or necrotic.
  • Look at the skin surface. For any lesion such as ulcerated or necrotic one, measure the distance to the nearest soft tissue margin.
  • Ink the surgical margins differently for soft tissue and bony margin(, including if the bony margin is a joint surface ("cartilaginous margin").)
Amputated finger after longitudinal split.
  • Split the digit longitudinally, either in the midline or at the closest margin between any ulcer and the soft tissue margin.
  • Let the tissue fix in formalin and then use a relatively strong decalcifying agent, usually at least 5-6 hours.

Tissue selection

Sections for microscopy are taken as follows:

For amputations disarticulated at the joint:

  • Perpendicular sections of the articular cartilage and adjacent bone. State which bone in key of sections.

For amputations resected by cutting across bone:

  • Ink the bone at the proximal margin, submit perpendicular section of bony margin.

Gangrene and/or suspected osteomyelitis:

  • Submit cross sections of each bone with associated ulcer and/or gangrene if appropriate, generally sagittal/longitudinal. Attempt to include the longitudinal distance from potential osteomyelitis to the proximal bony/cartilaginous margin.
  • Skin and soft tissues at proximal margin.
  • If margin is close to gangrene: perpendicular sections
  • If far, submit en face[note 2]
  • If you receive a separate thin or discoid bone slice, it is generally an additional bone margin. Preferably, have this decalcified and processed promptly, so that it may be used to make a preliminary report as to whether it is involved even before the main specimen is processed.

At least if osteomyelitis is suspected, ink all proximal (and/)or distal cut surfaces (differentially) of each slice, so that the pieces can be oriented, and the distance between osteomyelitis and the surgical margin can be estimated. The exception is where pieces can most definitely be anatomically oriented, such as the presence of a nail distally.

Gross report

Example:

(A. Labeled - ___. The specimen is received in formalin and consists of an amputated toe/finger.) The digit measures ___ cm in length and ___ cm in average diameter. The digit is resected ___ [[location]]. {{The proximal ___ cm of the specimen is not covered by skin and soft tissue.}} The skin and soft tissue margins appear <viable / necrotic>. The skin surface of the digit appears ___ {{and displays an (ulcerated/necrotic/gangrenous) lesion, cm from the cutaneous margin}}. The nail is <color/thickened/absent/necrotic>. The soft tissue surgical margin is inked blue [[for example]], and the <<bony surgical / cartilaginous>> margin of the ___ [[specific bone involved]] is inked green [[for example]]. On cut sections, the bone subjacent to the ulcer shows no gross abnormalities. Representative sections are submitted for microscopic examination in ___ cassettes following decalcification.
Key to sections:
  1. Longitudinal section through distal phalanx
  2. Longitudinal section through proximal phalanx, including <<bony surgical / cartilaginous>> margin
  3. Skin and soft tissues at proximal margin, submitted en face

Microscopic examination

Mainly, detect the presence of:

Microscopic report

Example:

(A. Left third toe, amputation:)
Toe with ulcer, gangrene and osteomyelitis. Osteomyelitis involves the distal phalanx, middle phalanx and proximal phalanx.
Osteomyelitis is 2.0 cm from the proximal articular surface of the proximal phalanx.
(The skin and soft tissue at the surgical margin appear viable.)


Bone

Grossing

To submit slides for microscopy, generally gross as follows:

  • Split the bone in the plane of interest for microscopy slides.
  • Fix the bone in formalin.
  • Perform decalcification of the specimen. First, generally take at least a small piece to be kept separately in formalin, in case the main specimen becomes necrotic, so that you have at least one more chance to decalcify it more lightly. If the order and/or history is suspicious for metastasis, try to sample a part of the specimen that is soft enough to not need decalcification (to avoid the risk that decalcification will impair later immunohistochemistry or other testing).
  • Take the sections of interest.

Microscopic evaluation

Look for any of the following:

Metastasis

Highly suspicious prostate adenocarcinoma metastasis can be confirmed with NKX1, TTF1 and CDX2.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. En face means that the section is tangential to the region of interest (such as a lesion) of a specimen. Further information: Gross_processing#Cutting

Main page

References


Image sources


Pituitary

Author: Mikael Häggström [note 1]

Microscopic evaluation

  • Look for cellular expansions, which in the anterior pituitary confers a loss of normal cellular heterogeneity.
  • If present, distinguish it as hyperplasia or neoplasia. If uncertain, by using reticulin immunohistochemistry, hyperplasia will show a preserved reticulin meshwork, whereas pituitary adenomas have disruption of it.[1]
  • For adenomas, unless otherwise indicated by the medical history, will generally by definition be of the silent type. Basophilic or acidophilic staining may give a clue about the subtype, but immunohistochemistry is generally required.

Microscopy report

In normal autopsy:

Adenohypophysis and neurohypophysis with no focal changes.

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Al-Brahim, N Y Y; Asa, S L (2006). "My approach to pathology of the pituitary gland ". Journal of Clinical Pathology 59 (12): 1245–1253. doi:10.1136/jcp.2005.031187. ISSN 0021-9746. 
  2. Drummond, Juliana; Roncaroli, Federico; Grossman, Ashley B; Korbonits, Márta (2019). "Clinical and Pathological Aspects of Silent Pituitary Adenomas ". The Journal of Clinical Endocrinology & Metabolism 104 (7): 2473–2489. doi:10.1210/jc.2018-00688. ISSN 0021-972X. 
    - "This article has been published under the terms of the Creative Commons Attribution License (CC BY; https://creativecommons.org/licenses/by/4.0/)"
  3. Gaballa, Salem; Lindsay, Jane; AlJaf, Avan; Hlaing, Kyaw M; Patel, Kashyap (2020). "Acute Unilateral Oculomotor Nerve Palsy as the Initial Presenting Sign of Nonfunctioning Apoplectic Gonadotroph Adenoma ". Cureus. doi:10.7759/cureus.8819. ISSN 2168-8184. 
    - "This is an open access article distributed under the terms of the Creative Commons Attribution License CC-BY 4.0"

Image sources


Clinical pathology

Author: Mikael Häggström, M.D. [note 1]

Memorization-worthy:[note 2] For the most likely types of cases and/or questions that you may be responsible for, know where to find local policies and procedures, and have a good idea of whom to ask for further advice. Make sure you have access and/or contact details for whenever and wherever you are likely to need them.


Blood bank

Author: Mikael Häggström [note 1]
If you expect to get questions regarding blood products, get a copy of the local cutoffs for approving transfusions of red blood cells, platelets and plasma, and keep it so that you can quickly look it up when needed.

Always consider if a blood product should be given as per a local precaution protocol (usually including regular check-ups of the patient).

Specific questions or requests

  • Generalized dosage in adults:
  • Plasma: Generally 10-15 ml/kg, and results in approximately 25-30% plasma volume replacement. Detailed calculation
  • Cryoprecipitate: 1 unit for every 7-10kg of body weight. 10 units generally replaces 100-150 mg/dl. Detailed calculation

Notes

  1. 1.0 1.1 For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. Further information on what is memorization-worthy or not: Learning pathology

Main page

References


Image sources


Blood compatibility testing

Author: Mikael Häggström [note 1]

Blood typing

ABO antigens and antibodies

Upon direct testing by adding antibodies against A, B and/or Rh to patient blood, agglutination means that the patient has the antigen tested. Upon indirect testing by adding A or B antigen to patient plasma, agglutination means absence of the antigen in the patient (and thus the patient produces antibodies against it).

Identification of non-ABO antibodies

In the antibody screening procedure, an individual's plasma is added to a panel of two or three sets of red blood cells which have been chosen to express most clinically significant blood group antigens. Agglutination of the screening cells by the plasma, with or without the addition of anti-human globulin, indicates that an unexpected blood group antibody is present. If this occurs, further testing using more cells (usually 10–11) is necessary to identify the antibody. By examining the antigen profiles of the red blood cells the person's plasma reacts with, it is possible to determine the antibody's identity as follows:

The image above shows the interpretation of an antibody panel used to detect antibodies towards the most relevant blood group antigens. Each row represents "reference" or "control" red blood cells of donors which have known antigen compositions and are ABO group O. A + means that the antigen is present on the reference red blood cells, and 0 means it is absent; nt means "not tested". The "result" column to the right displays reactivity when mixing reference red blood cells with plasma from the patient in 3 different phases: room temperature, 37°C and AHG (with anti-human globulin, by the indirect antiglobulin test).[1]

  • Step 1; Annotated in blue: starting to exclude antigens without reaction in all 3 phases; looking at the first reference cell row with no reaction (0 in column at right, in this case cell donor 2), and excluding (here marked by X) each present antigen where the other pair is either practically non-existent (such as for D) or 0 (presence is homozygous, in this case homozygous c).
    When both pairs are + (heterozygous cases), they are both excluded (here marked by X), except for C/c, E/e, Duffy, Kidd and MNS antigens (where antibodies of the patient may still react towards blood cells with homozygous antigen expression, because homozygous expression results in a higher dosage of the antigen).[2] Thus, in this case, E/e is not excluded in this row, while K/k is, as well as Jsb (regardless of what Jsa would have shown).[note 2]
  • Step 2: Annotated in brown: Going to the next reference cell row with a negative reaction (in this case cell donor 4), and repeating for each antigen type that is not already excluded.
  • Step 3: Annotated in purple. Repeating the same for each reference cell row with negative reaction.
  • Step 4: Discounting antigens that were absent in all or almost all reactive cases (here marked with \). These are often antigens with low prevalence, and while there is a possibility of such antibodies being produced, they are generally not the type that is responsible for the reactivity at hand.
  • Step 5: Comparing the remaining possible antigens for a most likely culprit (in this case Fya), and selectively ruling out significant differential antigens, such as with the shown additional donor cell type that is known to not contain Fya but contains C and Jka.

In this case, the antibody panel shows that anti-Fya antibodies are present. This indicates that donor blood typed to be negative for the Fya antigen must be used. Still, if a subsequent cross-matching shows reactivity, additional testing should be done against previously discounted antigens (in this case potentially E, K, Kpa and/or Lua).[1]

Hemagglutination inhibition[2]
Neutralizing substance Antigen cancelled
  • Hydatid cyst fluid
  • Pigeon eggs
P1
Saliva H, Lea
Breast milk I
Guinea pig urine Sda
Hemagglutination inhibition substances sound like they came from a witch brew!

When multiple antibodies are present, or when an antibody is directed against a high-frequency antigen, the normal antibody panel procedure may not provide a conclusive identification. In these cases, hemagglutination inhibition can be used, wherein a neutralizing substance cancels out a specific antigen.[2] Alternatively, the plasma may be incubated with cells of known antigen profiles in order to remove a specific antibody (a process termed adsorption); or the cells can be treated with enzymes such as ficain or papain which inhibit the reactivity of some blood group antibodies and enhance others (see table below).

Clinical implication

The following is a simplified classification for the main anti-erythrocyte antibodies, using mneumonics for the main involved antigen groups:

  • Anti-A/B antibodies: These will cause immediate hemolytic transfusion reaction if the red blood cells do not have compatible antigens, even if there is no previous exposure to the antigens. Therefore, blood transfusions must always be ABO compatible.
  • "Kickers"-class antibodies: Antibodies against Kidd, Kell, Rh, S and Duffy group antigens. These have a significant risk of causing hemolytic transfusion reactions when present, and therefore, patients with kickers-class antibodies should receive blood that is negative for the antigen, except for very critical situations where there is no time to find compatible blood.[3] Kickers-class antibodies generally need a previous exposure to the antigen to form, with transfusion reactions being possible upon subsequent transfusions.[2] Some patients first test positive and later test negative for a kickers-class antibody, but such patients must still be transfused with antigen-negative blood regardless.[4] They are generally of the IgG subtype, and are generally most active at 37°C.
  • "Limply"-class antibodies: Antibodies against Lutheran, Ii, M/N, P1, Lewis group antigens. These almost never cause clinically significant transfusion reactions (but anti-Ii antibodies are usually the type that causes cold agglutinin disease,[5] a form of autoimmune hemolytic anemia).[2] Hence, there is generally no need to find blood that is negative for the antigen for a limply-class positive patient. These antibodies are generally naturally occurring, that is, they don't require a previous exposure to the antigen to form. They are generally of the IgM class, and are generally not reactive at body temperature, but rather most active at room temperature and below.[6]

Following is a comparison of clinically relevant characteristics of antibodies against the main human blood group systems:[2]

ABO Rh Kell Duffy Kidd Lutheran MNS Lewis P Ii
Most common in immediate hemolytic transfusion reactions A Yes Fya Jka
Most common in delayed hemolytic transfusion reactions E,D,C Jka
Most common in hemolytic disease of the newborn Yes D,C Yes
Commonly produce intravascular hemolysis Yes Yes Yes
Reactive at room temperature Yes M,N Lea, Leb P1
Nearly always clinically insignificant Yes M,N Yes P1
Naturally occurring Yes Yes M,N Yes Yes Yes
Enhanced by ficain[7] and papain[8] Yes Yes Yes Yes P1 Yes
Destroyed by ficain[7] and papain[8] Fya, Fyb Yes Yes
Displaying dosage Further information: Blood compatibility testing Cc, Ee Yes Yes Yes

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. Besides from C/c, E/e, Duffy, Kidd and MNS, clinically significant dosage effects is rare but not impossible for other antigens, which thus may still be considered if subsequent cross-matching is reactive.

Main page

References

  1. 1.0 1.1 Justin R. Rhees, M.S., MLS(ASCP)CM, SBBCM. Introduction to Antibody Identification. University of Utah, Medical Laboratory Sciences.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Mais, Daniel (2014). Quick compendium of clinical pathology . United States: American Society for Clinical Pathology Press. ISBN 978-0-89189-615-9. OCLC 895712380. 
  3. Pamela P. Goodell, Lynne Uhl, Monique Mohammed, Amy A. Powers (2010). "Risk of Hemolytic Transfusion Reactions Following Emergency-Release RBC Transfusion ". American Journal of Clinical Pathology 134 (2). doi:10.1309/AJCP9OFJN7FLTXDB. 
  4. Uhl, L (11 Jan 2021). Pretransfusion testing for red blood cell transfusion. UpToDate.
  5. "Autoimmune hemolytic anemia: current knowledge and perspectives ". Immunity & Ageing 17 (1): 38. November 2020. doi:10.1186/s12979-020-00208-7. PMID 33292368. 
  6. Ferdowsi S, Mohammadi S, Ahmadnezhad M, Herfat F, Rezvani A, Eshghi P (2022). "Anti-M antibody and ABO blood grouping discrepancy: a report of three cases with review of literature. ". Hematol Transfus Cell Ther 44 (2): 288-290. doi:10.1016/j.htct.2020.09.150. PMID 33358685. PMC: 9123591. Archived from the original. . 
  7. 7.0 7.1 Hill, Ben C.; Hanna, Courtney A.; Adamski, Jill; Pham, Huy P.; Marques, Marisa B.; Williams, Lance A. (2017). "Ficin-Treated Red Cells Help Identify Clinically Significant Alloantibodies Masked as Reactions of Undetermined Specificity in Gel Microtubes ". Laboratory Medicine 48 (1): 24–28. doi:10.1093/labmed/lmw062. ISSN 0007-5027. PMID 28007780. 
  8. 8.0 8.1 Eric Ching. Questions and Answers on Proteolytic Enzymes Used in Blood Group Serology. Canadian Society for Transfusion Medicine.

Image sources


Kleihauer–Betke test

Author: Mikael Häggström [note 1]
The Kleihauer–Betke test stains fetal red blood cells (cells containing HbF) dark reddish-pink, while adult red blood cells will be white to light pink.

Collection

EDTA-containing-tube.

Criteria for fetal cells

KB stain with green marks at cells counted as fetal (HbF) cells, and red marks at incompletely colored cells at top and a too small cell at right.

To count, a fetal blood cell should be:

  • Stained more than approximately half of what is seen in control.
  • Not be nucleated or too big (white blood cell are generally also stained).
  • Not be too small.

Semi-quantification

This is done for Rh-positive mothers to estimate the severity of a suspected feto-maternal hemorrhage, which can be suspected by various clinical findings (including neonatal anemia, stillbirth, intrauterine growth restriction, hydrops fetalis, decreased or absent fetal movements, non-reassuring fetal heart rate tracing, sinusoidal fetal tracing, and fetal tachyarrythmias, placenta previa with bleeding, and placental abruption)[1].

10HPFs (in 40x) are scanned, and fetal RBCs are counted (cells per 10 HPFs, not average per HPF), and classified as:

  • 0 - Negative
  • 1 - Rare
  • 2-5 - Few
  • 6-10 - Moderate
  • >10 - Abundant

Quantification

This is done for Rh-negative mothers to estimate the number of Rho(D) immune globulin vials to administer.

2000 cells are counted, in order to give a percentage calculated as:

  • Fetal RBCs (given in%) = (Fetal RBC count) / (Total cell count) *100

Alternatively, an acceptable estimation of at least 2000 cells can be done by using a micrograph (or a microscopy grid) to estimate the mean number of cells in a certain area, and using the same mean to estimate the number of cells in equally sized areas:
1. Count cells (both adult and fetal) until reaching 100 cells (including each cell in square by square if using a microscopy grid). Take note of how large micrograph area (or how many grid squares) were counted (here designated as x amount), and how many fetal RBCs were counted.
2. Pick another random location (you may randomize again if it is of a significantly different cell density, but do not let your decision be influenced by the number of fetal RBCs in the area or near its edge). Count the total number of cells in the same area size (or same x number of squares), and how many of them are fetal RBCs.
3. Pick another location again, and count the number of cells in the same area size, and how many of them are fetal RBCs.

  • If a count of 200-300 cells only shows 0 or 1 fetal RBC, there only needs to be 1 vial of 300 micrograms Rho(D) immune globulin, and the rest of the steps in this section can be skipped.
Standard
deviation
Count cells
in following
number of areas
Up to 6 3
7 4
8 5
9 6-7
10 8
11 10
12 12
  • Calculate how much the count for the second and third areas deviated from 100, and take the average thereof, which will be used as standard deviation.[note 2] If the standard deviation is higher than 12, count a total of 2000 cells regardless of areas and calculate as per formula above, and the rest of the steps can be skipped.
  • Use the table at right to estimate how many areas in total you need to count in order to have a mean number of cells per area with an acceptable confidence interval.

4. After having counted the needed number of areas, calculate the average of the number of cells per area (or per x number of squares), and assume that number for the rest of the counting.
5. Divide 2000 by the number of cells per area, and round that up to know the number of areas you need to perform the next step on in order to presumably have a total of 2000 cells (including previously counted areas).
6. In those additional areas, only count the number of fetal cells per area (or x number of squares), and add that to the fetal cells from previous areas.

Fetal RBCs (given in%) = (Fetal RBC count) / (Presumable total cell count) *100

Example:

The sum of all fetal RBCs in all areas in this example is 45. The presumable total cell count is 103 * 20 = 2060. Thus:

  • Fetal RBCs (given in%) = 45 / 2060 * 100 = 2.2%

Calculation of number of vials

Assuming that a vial of 300 micrograms of Rho(D) immune globulin will protect against 30 mL of fetal blood, the number of vials needed to compensate for the fetal-maternal transfusion is calculated as following, rounded up,[2] or rounded to the closest full number and then adding 1.[3]

Number of vials = Fetal RBCs in% * 1.7

For example, with 2.2% fetal RBCs, the number of vials would be 4[2] or 5[3].

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.
  2. 2.0 2.1 Technically, the standard deviation would be calculated as the average deviation from the mean of all areas, but the simplified calculation used in this resource can be regarded to be close enough for practical purposes.

Main page

References

  1. Solomonia N, Playforth K, Reynolds EW (2012). "Fetal-maternal hemorrhage: a case and literature review. ". AJP Rep 2 (1): 7-14. doi:10.1055/s-0031-1296028. PMID 23946896. PMC: 3653511. Archived from the original. . 
  2. 2.0 2.1 Diann M. Krywko. Kleihauer Betke Test. StatPearls, National Center for Biotechnology Information. Last update: Last Update: January 20, 2020.
  3. 3.0 3.1 Practice at Danbury Hospital, Danbury, Connecticut, New England.

Image sources


Peripheral blood smear

Author: Mikael Häggström [note 1]
Look at and comment separately on white blood cells, red blood cells and platelets. You generally don't need to aim for a perfect report, because for most purposes, a peripheral smear is a relatively simple screening test, and clinicians may opt to perform for example flow cytometry and/or a bone marrow biopsy if they want a better evaluation.

Comprehensiveness

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))
Other legend

<< Decision needed between alternatives separated by / signs >>
{{Common findings / In case of findings}}
[[Comments]]
Link to another page

Oil immersion microscopy

This is preferred for light microscopy of peripheral blood smears in order to achieve a very high magnification. First use low or medium power to center on suspicious cells, or where red or white blood cells are best appreciated. Put a drop of immersion oil on the location and switch to the immersion objective. Then, whenever there's oil on a slide, always think twice before switching between objectives so as to avoid getting oil on any of your dry objectives (which is a bit tedious to clean off).

Red blood cells

Automated values

When available, automatic quantification of mean corpuscular volume (MCV) and red blood cell (RBC) distribution width (RDW), usually as part of CBC panel, generally decides whether you will call the sample "normocytic" versus "microcytic"/"macrocytic" and/or "anisocytotic", even if it is not clearly visible in the microscope. If automated values are not available, compare RBC sizes to lymphocyte nuclei, which should normally be the same size. If mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) are normal, but you still see multiple RBCs with central pallor greater than 50% of the diameter, you can report it as "Increased central pallor", and you may add "indicating iron deficiency" if it is compatible with the clinical history.

Automated values can be graded as follows:[1]

Interpretation Mild Moderate Marked
Microcytosis MCV : 70 - 79 MCV : 60 - 69 MCV <60
Macrocytosis MCV : 100 - 115 MCV : 115 - 125 MCV >125
Hypochromasia MCH : 23 - 26 MCH : 21 - 23 MCH <20
Anisocytosis RDW: 14.5[2] or 16[1] - 18 RDW : 18 - 22[1] or 26[2] RDW > 22[1] or 26[2]

Morphologic findings

Look for poikilocytosis (red blood cells of abnormal shapes). These are counted as a percentage of visible red blood cells:[1]

Image Rare/Occasional Moderate amount of Many/Abundant
Polychromasia Peripheral blood smear with polychromasia.jpg 3 - 5% 5 - 25% >25%
Spherocytes Micrograph of a spherocyte.jpg 1 - 5% 5 - 25% >25%
Schistocytes Micrograph of schistocytes.jpg up to 2% 2 - 25% >25%
Target cells (codocytes) Micrograph of a target cell.jpg up to 3% 3 - 25% >25%
Tear drop cells Micrograph of a tear drop cell (dacrocyte).jpg up to 2% 2 - 25% >25%
Burr cells (echinocytes) Micrograph of an echinocyte on a peripheral blood smear.jpg 1 - 3% 3 - 10% >10%
Sickle cells (drepanocytes) Micrograph of a sickle cell.jpg 3 - 5% 5 - 25% >25%
Elliptocytes Micrograph of an elliptocyte on a peripheral blood smear 02.jpg 1 - 5% 5 - 25% >25%
Basophilic stipplings Micrograph of a red blood cell with basophilic stippling.jpg up to 2% 2 - 25% >25%
Howell Jolly bodies Micrograph of a Howell–Jolly body in a red blood cell.jpg up to 1% 2 - 3 % >3%
Burr cells versus spur cells

Burr cells are distinguished from spur cells by having more equally distributed and rounded projections. They are usually artifactual. However, they may also be caused by renal insufficiency, so if this is present, a report may include "Occasional/Multiple echinocytes, consistent with renal insufficiency".

Intraerythrocytic findings

Platelets

If CBC is performed, use count to determine whether platelets are "normal in number" or whether there is "thrombocytopenia" or "thrombocytosis". If no CBC, count platelets within a high power oil immersed field, which should normally be 8 to 20.

A giant platelet.

Large platelets are those with a diameter greater than 4 microns. Giant platelets are those with a diameter greater than 7 microns (larger than a normal red blood cell).[3] Example report:

Numerous large and giant platelets(, suggesting an increased platelet turnover)(( such as in immune thrombocytopenic purpura. They may also be present in myeloproliferative neoplasms, myelodysplasia, and some congenital thrombocytopenia syndromes, including Bernard-Soulier syndrome and MYH9-related disorders.[3]))

In thrombocytopenia from automatic counting, look in particular for:

  • Clumping of platelets (which can cause a falsely low automatic platelet count). If present, check with the lab if it was sent in EDTA (which may cause artefactual clumping) and ask to have a blood sample sent in sodium citrate instead. Also, look for satellitosis (platelets attached around white blood cells).
  • Schistocytes among red blood cells.

White blood cells

Comparison of monoblast, promonocyte and monocyte. Further information: Suspected blasts on peripheral blood smear

Look for:

Report

Example report:

Normochromic normocytic red blood cells. Red blood cells show <normal morphology / anisopoikilocytosis with occasional ___>. [[If thrombocytopenia, also add "Schistocytes are not significantly increased" if applicable.]]

{{Leukocytosis with neutrophilia / lymphocytosis.}} White blood cells show no left shift or blasts.

Platelets show no evidence of clumping, and show normal granularity.

(Causes of the above findings include ___.)

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. 1.0 1.1 1.2 1.3 1.4 Unless otherwise specified in table, reference is:
    - . Hong Kong Medical Technology Association - Quality Assurance Programme - Haematology and Serology, Prepared by HKMTAQAP Haematology & Serology Panel on November 2002..
  2. 2.0 2.1 2.2 . High RDW level in the blood. MrLabTest. Last update: 12/01/2021
  3. 3.0 3.1 Teresa Scordino (2016-12-02). Giant platelets. American Society of Hematology.
  4. Glassy, Eric (1998). Color atlas of hematology : an illustrated field guide based on proficiency testing . Northfield, Ill: College of American Patholgists. ISBN 978-0-930304-66-9. OCLC 40976106. 
  5. . prolymphocytes in PLL. American Society of Hematology (2013-07-16).
  6. Fredrick L. Kiechle. Q & A. CAP Today. June 2010

Image sources


Platelet aggregation study

Author: Mikael Häggström [note 1]

On for example optical densitometry, a first and second wave of platelet aggregation is seen, in this case for an ADP-initiated aggregation.[1]

In a platelet aggregation study, the aggregation process is started by different agonists (ADP, epinephrine etc.) and the aggregation pattern can usually conform into any of the following patterns:

Platelet aggregation function by disorders and agonists
ADP Epinephrine Collagen Ristocetin
P2Y receptor defect[2] (including Clopidogrel) Decreased Normal Normal Normal
Adrenergic receptor defect[2] Normal Decreased Normal Normal
Collagen receptor defect[2] Normal Normal Decreased or absent Normal
  • Von Willebrand disease[3]
  • Bernard–Soulier syndrome[2]
Normal Normal Normal Decreased or absent
  • Glanzmann's thrombasthenia[2]
  • Afibrinogenemia
Decreased Decreased Decreased Normal or decreased
Storage pool deficiency[3] Absent second wave Partial
Aspirin or aspirin-like disorder Absent second wave Absent Normal

Further reading

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Jiang, L.; Xu, C.; Yu, S.; Liu, P.; Luo, D.; Zhou, Q.; Gao, C.; Hu, H. (2013). "A critical role of thrombin/PAR-1 in ADP-induced platelet secretion and the second wave of aggregation ". Journal of Thrombosis and Haemostasis 11 (5): 930–940. doi:10.1111/jth.12168. ISSN 15387933. PMID 23406164. 
  2. 2.0 2.1 2.2 2.3 2.4 Borhany, Munira; Pahore, Zaen; ul Qadr, Zeeshan; Rehan, Muhammad; Naz, Arshi; Khan, Asif; Ansari, Saqib; Farzana, Tasneem; et al. (2010). "Bleeding disorders in the tribe: result of consanguineous in breeding ". Orphanet Journal of Rare Diseases 5 (1). doi:10.1186/1750-1172-5-23. ISSN 1750-1172. 
  3. 3.0 3.1 . Why Perform Platelet Aggregation?. Helena Biosciences. 2015

Image sources


Bone marrow

Author: Mikael Häggström [note 1]

Bone marrow aspirate showing normal "trilineage hematopoiesis":
- Myelomonocytic cells: an eosinophil myelocyte marked
- Erythroid cells: an orthochromatic erythroblast marked
- Megakaryocytic cells.

Autopsy

Using pliers or similar tool, squeeze some bone marrow from a rib.

Microscopic evaluation

  • Confirm trilineage hematopoiesis (see image).
  • Look for apparent cellular atypia or decrease of cellular diversity.

Report

Example in a normal case:

Bone marrow from rib (or other location if applicable): Trilineage hematopoiesis. There is no evidence of malignancy.

Bone marrow biopsy

Gross processing

  • Ensure that the biopsy is properly fixed (generally at least 2 hours).
  • Measure length and diameter of each fragment.
  • If the biopsy is received in a zinc-containing fixative, rinse it for about 2 minutes, such as placing the cassette in a container under running water (and block any sink enough so that the cassette won't float away).
Histopathology of bone marrow with insufficient decalcification, wherein the bony trabeculae may get pushed by the microtome blade and plow away the cells of interest as displayed. To compensate, thicker sections may be taken, also making evaluation harder.
  • Put in decalcifying solution, preferably using a type that is optimal for performing subsequent immunohistochemistry. Generally decalcify the specimen for about 15 minutes initially, and palpate the specimen to check whether it is still firm. If it is, decalcify another 5-10 minutes and check again. Rather have it a little bit too soft than a little bit too firm. Be careful to follow grossing guidelines for bone marrows, since even a small aberration in the processing is likely to be noticed as creating artifacts.
Gross report example
The specimen is received in AZF solution and consists of __ core needle bone marrow biopsy fragment(s) measuring __ cm in length and 0.2 cm in diameter. The specimen is entirely submitted for microscopic examination in one cassette following decalcification.

Microscopic evaluation

Evaluate the following:

Bone marrow aspirate

Find a location where bone marrow cells can be seen individually, preferably with minimal peripheral blood among them. Sometimes it is between trabeculae and sometimes it is in the surrounding area. Perform a differential count by counting 500 cells[1] and dividing the numbers by 5 to get their percentages. Don't count cells that don't have a cytoplasm or nucleus. If you receive several slides, count about the same number of cells from each slide, but don't count cells from slides where the cell types are more indistinct.

  • Myeloid/erythroid ratio, usually defined as the ratio between the number of neutrophil granulocytes and precursors versus the number of erythroblasts. Depending on source, the lower limit of the normal range for this ratio bone marrow aspirate smears in adults is 1 to 2, and the upper limit is 5 to 8.[2] In histologic sections, the normal range is 1.5 – 3.0.[2] Some hematologists also include eosinophils, basophils and monocytes, as well as their precursors, in the myeloid number, but this has only a minor effect on the M:E ratio in normal individuals.[2] Still, if you are to calculate the value for a senior, check their preference first.

In a bone marrow count, nucleated red blood cells count into the total percentage of cells (but does not count into percentage of white blood cells in peripheral blood).

Bone marrow biopsy, H&E stain
  • Adequacy: There should preferably be 5 intertrabecular spaces.
  • Cellularity: This is a rather rough estimation of the area of hematopoietic cells divided by the area of all intertrabecular matter, which otherwise mainly consists of fat cells and a small interstitial space. Areas of bone, hemorrhage or artifacts are not counted. In patients 20-80 years, the percentage should be about 100 minus age, such as 40% in a 60 year old patient.
  • Thrombopoiesis: There are normally about 3 megakaryocytes per 40x field.
  • Look for any granuloma or cancer metastasis
Bone marrow biopsy, other stains

Generally including:

Ring sideroblast, defined by five or more perinuclear iron granules that encompass at least 1/3 of the nuclear circumference.[3]
  • Iron stain: Look at approximately 100 cells and semi-quantify the presence of any ring sideroblasts.
  • Reticulin to grade the amount of fibrosis.
  • CD3 and CD20 to highlight T and B cells, respectively.

Microscopic report

Example template:

On this resource, the following formatting is used for comprehensiveness:

  • Minimal depth
  • (Moderate depth)
  • ((Comprehensive))
Other legend

<< Decision needed between alternatives separated by / signs >>
{{Common findings / In case of findings}}
[[Comments]]
Link to another page

SOURCE:

Bone marrow aspirate and biopsy

CLINICAL INFORMATION:

{{Lymphocytosis / Pancytopenia / Anemia etc }}

DIAGNOSIS:
PERIPHERAL BLOOD:

{{Lymphocytosis / Pancytopenia / Anemia etc }}

BONE MARROW, {{POSTERIOR ILIAC CREST,}} ASPIRATE AND BIOPSY:

{{Chronic/Acute lymphocytic/myeloid leukemia.}}
See description and comment.

GROSS DESCRIPTION:

[[As per gross report above.]]

MICROSCOPIC DESCRIPTION:

PERIPHERAL SMEAR:

MORPHOLOGY:

  • Red Blood Cells: No significant abnormality.
  • White Blood Cells: No significant abnormality.
  • Platelets: No significant abnormality.

BONE MARROW ASPIRATE:

Left / RIGHT / UNDESIGNATED SITE

CELLULARITY ESTIMATE: Adequate. / Hypocellular and hemodilute. / Hypercellular. / Too few cells for morphologic evaluation.

MARROW DIFFERENTIAL

  • Erythroblasts: __%
  • Blasts: __%
  • Neutrophils/precursors: __%
  • Eosinophils: __%
  • Basophils: __%
  • Lymphocytes: __%
  • Monocytes: __%
  • Plasma Cells: __%
  • M:E ratio: __:__

ERYTHROPOIESIS: Maturing.

GRANULOPOIESIS: Maturing.

MEGAKARYOCYTES: Present.

LYMPHOCYTES: Mature.

PLASMA CELLS: Rare without atypia.

BONE MARROW TOUCH PREPARATION: _

BONE MARROW BIOPSY:

Left / RIGHT / UNDESIGNATED SITE

SPECIMEN ADEQUACY:

Satisfactory. / Limited. / Unsatisfactory.

CELLULARITY:_

_%: Normocellular / Hypercellular / Hypocellular for age. / Variable ( _ %- _ %, overall _ %) / Cannot assess cellularity due to small biopsy. {{With aspirative artifact.}}

Decalcified bone marrow biopsy demonstrates ____________________

BM Erythropoiesis _

BM Cellularity _

BM Megakaryocytes _

BM Myelopoiesis _

BONE MARROW IRON STAIN: Storage iron _/4 on aspirate smear with / without ring sideroblasts.

SPECIAL STAINS:

Reticulin Stain: ___ reticulin fibrosis (_+/3+)

FLOW CYTOMETRY:

No immunophenotypic evidence for abnormal myeloid maturation, an increase in blasts, or a lymphoproliferative disorder (see attached report).

COMMENT:

{{Cytogenetic study and next generation sequencing panel for myeloid neoplasm are pending.}}
All stains have functional controls.


Forensic pathology

Author: Mikael Häggström [note 1]

Estimation of time of death

An estimation of the time of death is made by postmortem changes of the body. A very approximate rule of thumb for estimating the postmortem interval is as follows:[4]

  • Warm and flaccid: less than 3 hours
  • Warm and stiff: 3 to 8 hours
  • Cold and stiff: 8 to 36 hours
  • Cold and flaccid: More than 36 hours.

Notes

  1. 1.0 1.1 For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. Abdulrahman AA, Patel KH, Yang T, Koch DD, Sivers SM, Smith GH (2018). "Is a 500-Cell Count Necessary for Bone Marrow Differentials?: A Proposed Analytical Method for Validating a Lower Cutoff. ". Am J Clin Pathol 150 (1): 84-91. doi:10.1093/ajcp/aqy034. PMID 29757362. Archived from the original. . 
  2. 2.0 2.1 2.2 BJ. Bain (2017-02-19). Chapter 5: Pathology of the marrow. Basicmedical Key.
  3. Salama M, Teruya-Feldstein J, Kremyankaya M. Atlas of Diagnostic Hematology. Philadelphia, PA: Elsevier; 2021.
  4. Senior, T (2018). Forensic ecogenomics : the application of microbial ecology analyses in forensic contexts . London, United Kingdom San Diego, CA: Academic Press. ISBN 978-0-12-809360-3. OCLC 1023028365. 

Image sources

  1. Image(s) by: Mikael Häggström et al. - using source images from multiple authors (full list is located at image page in Wikimedia Commons.
    Attribution 4.0 International license

Career choice

Author: Mikael Häggström [note 1]

Subspecialization

The most useful goal is arguably to become a subspecialist in a particular field within pathology, for which you can be a go-to person when other pathologists need help, and at the same time maintaining basic skills in handling general pathology, at least for the most common conditions where you are expected to practice. In either case, it is important to be able to extend beyond your comfort zone when needed, and at least try to solve cases that fall outside the official subspecialties of the pathologists at hand, even if you may need to search for someone to consult you for the case.

Judge subspecialties primarily by their presumed everyday work, and how well it fits with your personal strengths and weaknesses. As much as possible, base your evaluation on real life exposure to the practice, and put only minimal weight on how interesting the theoretical literature thereof is.

To some degree, consider whether you will want to live and work in (or commute to) a larger city (with more demand to dedicate yourself to a narrow-scoped subspecialty), or a relatively smaller town (with an increased demand for broader or otherwise generally needed subspecialties, mainly surgical pathology and cytopathology but mostly also hematopathology).

Notes

  1. For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References


Image sources


Teaching pathology

Strive to always begin with the real life situation in which the point you want to teach is relevant for improving the management of a patient. If you can't think of a situation where something would relevant, generally don't teach it. Also, present them with all pertinent information that you can readily look up or ask from fellow trainees.

If possible, teach by giving students tasks from real cases and present to you what they would do. Until you know a student better, assume that the person is uneducated enough to need to ask or look up how to do something, but at the same time smart enough to only study what is needed to perform the task, so a greater responsibility means a greater need to study.

When making MCQs, keep the presentation brief, with only little irrelevant and/or misleading information. Everyday pathology work offers enough practice in finding the relevant information among medical records, lab results etc.

Only expect memorization to what is memorization-worthy (see the Learning pathology chapter). Memorized does not mean teach-worthy; just because you've memorized something yourself doesn't automatically mean it's worthy of memorization for others.


Notes


References


Image sources