Difference between revisions of "Skin"

From patholines.org
Jump to navigation Jump to search
(→‎Microscopic evaluation: +seborrheic keratosis)
(31 intermediate revisions by the same user not shown)
Line 3: Line 3:
 
|author2=
 
|author2=
 
}}
 
}}
 
+
For skin specimens in general:
==Fixation==
+
{{Fixation - standard}}
*'''Generally''': Buffered 4% formaldehyde.<ref name=kvast>{{cite web|url=http://www.svfp.se/foreningar/uploads/L15178/kvast/hud/Handlaggning%20av%20hudprover%20%20provtagningsanvisningar%20utskarningsprinciper%20och%20snittning%2020150325.pdf|title=Handläggning av hudprover – provtagningsanvisningar, utskärningsprinciper och snittning (Handling of skin samples - Instructions for sampling, cutting and incision|author=Katarzyna Lundmark, Krynitz, Ismini Vassilaki, Lena Mölne, Annika Ternesten Bratel|accessdate=2019-09-09|website=KVAST (Swedish Society of Pathology)}}</ref>
+
{{Fixation - general notes}}
*Suspected '''immunologic disease''':<ref name="ChhabraMinz2012">Page 678 in: {{cite journal|last1=Chhabra|first1=Seema|last2=Minz|first2=RanjanaWalker|last3=Saikia|first3=Biman|title=Immunofluorescence in dermatology|journal=Indian Journal of Dermatology, Venereology, and Leprology|volume=78|issue=6|year=2012|pages=677|issn=0378-6323|doi=10.4103/0378-6323.102355|url=https://pdfs.semanticscholar.org/23d0/148dbe342a93e0bc65a6a2e31040a89113ba.pdf}}</ref> Fixation for immunofluorescence, with for example [[Michel's solution]].<ref name=kvast/> ''For details, see [[immunofluorescense of skin tissues]]''
+
*Suspected '''immunologic disease''':<ref name="ChhabraMinz2012">Page 678 in: {{cite journal|last1=Chhabra|first1=Seema|last2=Minz|first2=RanjanaWalker|last3=Saikia|first3=Biman|title=Immunofluorescence in dermatology|journal=Indian Journal of Dermatology, Venereology, and Leprology|volume=78|issue=6|year=2012|pages=677|issn=0378-6323|doi=10.4103/0378-6323.102355|url=https://pdfs.semanticscholar.org/23d0/148dbe342a93e0bc65a6a2e31040a89113ba.pdf}}</ref> Fixation for immunofluorescence, with for example [[Michel's solution]].<ref name=kvast>{{cite web|url=http://www.svfp.se/foreningar/uploads/L15178/kvast/hud/Handlaggning%20av%20hudprover%20%20provtagningsanvisningar%20utskarningsprinciper%20och%20snittning%2020150325.pdf|title=Handläggning av hudprover – provtagningsanvisningar, utskärningsprinciper och snittning (Handling of skin samples - Instructions for sampling, cutting and incision|author=Katarzyna Lundmark, Krynitz, Ismini Vassilaki, Lena Mölne, Annika Ternesten Bratel|accessdate=2019-09-09|website=KVAST (Swedish Society of Pathology)}}</ref> ''For details, see [[immunofluorescense of skin tissues]]''
{{Fixation}}
+
<noinclude>
 
 
 
==Presentations==
 
==Presentations==
===Dark skin focalities===
 
[[File:Dark skin focalities.jpg|thumb|center|Dark skin focalities (in this case, from top left and clockwise: Spitz nevus, seborrheic keratosis, elevated melanocytic nevus and melanoma)]]
 
Skin with one or more areas that are darker than the surroundings.
 
 
====Microscopic evaluation====
 
[[File:Pie chart of incidence and malignancy of pigmented skin lesions.png|thumb|370px|Various diagnoses of pigmented skin lesions, by relative incidence upon biopsy, and malignancy potential.]]
 
Evaluation is largely based on the relative incidence and malignancy of various differential diagnoses (see pie chart). Main approaches are:
 
*Direct pattern recognition
 
*Systematic
 
 
;Pattern recognition
 
 
<gallery>
 
<gallery>
File:Histopathology of melanocytic nevus.jpg|Melanocytic nevus
+
File:Dark skin focalities.jpg|link=Dark skin focalities|[[Dark skin focalities]]
File:Histopathology of melanoma, HE.jpg|Melanoma
+
File:Gross pathology of cystic nodular hidradenoma.jpg|link=Skin cysts|[[Skin cysts]]
File:Blue nevus (4 of 4) (2797064219).jpg|Blue nevus
 
File:Histopathology of seborrheic keratosis.jpg|Seborrheic keratosis
 
 
</gallery>
 
</gallery>
 +
===Most common requests===
 +
*[[Suspected malignant skin excisions]]
 +
:*[[Melanoma in situ]]
 +
:*[[Invasive melanoma of the skin]]
 +
:*[[Basal-cell carcinoma]]
 +
:*[[Squamous-cell carcinoma of the skin]]
 +
*[[Dermatitis]]
 +
*[[Benign non-inflammatory skin conditions]]
 +
:*[[Dysplastic nevus]]
 +
*[[Wound]]
 +
{{Gross processing of skin excisions}}
 +
</noinclude>
  
;Systematic
+
==Microscopic evaluation==
By their relative incidences, one practical approach is:
+
If the referral does not point to any particular request (see "[[#Most common requests|Most common requests]]" above), the following algorithm may be applied:
*Is it a dysplastic (melanocytic) nevus? If not:
+
*Is it a '''[[suspected malignant skin excisions|suspected malignant skin excision]]'''? If not:
*Is it a melanoma? If not:
+
*If primarily inflammatory, evaluate as '''[[dermatitis]]'''. If none of these, evaluate as:
*Compare to patterns of various other possibilities.
+
*'''[[Benign non-inflammatory skin conditions]]'''
  
</noinclude>
+
In '''intraoperative''' consultations by frozen section, it is generally sufficient to report clear margins if present, and specification of the type of tumor can be deferred to permanent sections.
 +
 
 +
==Reporting==
 +
''Preferably see specific articles from algorithm in section above.''
 +
*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/Least distance to a margin
 +
:*Perineural or vascular invasion if present
 
{{Bottom}}
 
{{Bottom}}

Revision as of 13:57, 4 March 2021

Author: Mikael Häggström [note 1]
For skin specimens in general:

Fixation

Generally 10% neutral buffered formalin.

  See also: General notes on fixation


Presentations

Most common requests

Gross processing of skin excisions

Gross pathologic processing of skin excisions[3][note 2]
Lesion size
<4 mm 4 - 8 mm 9 - 15 mm
Benign appearance

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

Suspected malignancy 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 referral does not point to any particular request (see "Most common requests" above), the following algorithm may be applied:

In intraoperative consultations by frozen section, it is generally sufficient to report clear margins if present, and specification of the type of tumor can be deferred to permanent sections.

Reporting

Preferably see specific articles from algorithm in section above.

  • 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/Least distance to a margin
  • Perineural or vascular invasion if 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.
  2. The excision examples show a normal mole (upper row, benign appearance) and a superficial basal cell carcinoma (lower row, suspected malignancy).

Main page

References

  1. 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. . 
  2. 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.
  3. 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.

Image sources