Lymph nodes

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Author: Mikael Häggström [notes 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 cytometry).

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.[notes 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.
  • Serially section the specimen. Lymph nodes less than 5 mm may be submitted whole, while larger lymph nodes may be sectioned at 2-3 mm intervals.[1]
  • If you will submit multiple bisected lymph nodes in the same cassette, ink each lymph node differently, so that the number of lymph nodes involved by any pathology can be counted.

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.[2][3] However, there is regional variation as detailed in this table:
Upper limit of lymph node sizes in adults
Generally 10 mm[2][3]
Inguinal 10[4] – 20 mm[5]
Pelvis 10 mm for ovoid lymph nodes, 8 mm for rounded[4]
Neck
Generally (non-retropharyngeal) 10 mm[4][6]
Jugulodigastric lymph nodes 11mm[4] or 15 mm[6]
Retropharyngeal 8 mm[6]
  • Lateral retropharyngeal: 5 mm[4]
Mediastinum
Mediastinum, generally 10 mm[4]
Superior mediastinum and high paratracheal 7mm[7]
Low paratracheal and subcarinal 11 mm[7]
Upper abdominal
Retrocrural space 6 mm[8]
Paracardiac 8 mm[8]
Gastrohepatic ligament 8 mm[8]
Upper paraaortic region 9 mm[8]
Portacaval space 10 mm[8]
Porta hepatis 7 mm[8]
Lower paraaortic region 11 mm[8]

Lymphadenopathy of the axillary lymph nodes can be defined as solid nodes measuring more than 15 mm without fatty hilum.[9] Axillary lymph nodes may be normal up to 30 mm if consisting largely of fat.[9]

In children, a short axis of 8 mm can be used.[10] 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.[11]

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.[12]

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 __(.(The entire specimen is submitted for microscopic examination in one cassette.)
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

Look for:

  • Whatever pathology is indicated by the referral, or findings in other submitted specimens.
  • General screening:
Lymph node metastasis from a neuroendocrine tumor of the midgut.
  • Any metastasis, which usually looks similar to the primary tumor (neuroendocrine tumor in picture at right).
  • Enlargement, as preferably measured during grossing, but can possibly be made on the microscopy slide. If present, see section below:

Microscopy of enlarged lymph nodes

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

  • Paracortical hyperplasia: Reactive paracortical hyperplasia shows expansion of paracortical areas by a mixed infiltrate, often having a mottled appearance, and it usually has a concomitant reactive follicular hyperplasia.[14] 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.[14]
  • Unspecific hyperplasia: An unspecific pattern of lymph node enlargement, without atypical cells, next to an inflamed area, may simply be diagnosed as "benign reactive lymph node".

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. 2.0 2.1 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. 
  3. 3.0 3.1 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. 
  4. 4.0 4.1 4.2 4.3 4.4 4.5 "Current concepts in lymph node imaging ". Journal of Nuclear Medicine 45 (9): 1509–18. September 2004. PMID 15347718. 
  5. . Assessment of lymphadenopathy. BMJ Best Practice. Retrieved on 2017-03-04. Last updated: Last updated: Feb 16, 2017
  6. 6.0 6.1 6.2 Page 432 in: Luca Saba (2016). Image Principles, Neck, and the Brain . CRC Press. ISBN 9781482216202. 
  7. 7.0 7.1 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. . 
  8. 8.0 8.1 8.2 8.3 8.4 8.5 8.6 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. 
  9. 9.0 9.1 Page 559 in: Wolfgang Dähnert (2011). Radiology Review Manual . Lippincott Williams & Wilkins. ISBN 9781609139438. 
  10. Page 942 in: Richard M. Gore, Marc S. Levine (2010). High Yield Imaging Gastrointestinal HIGH YIELD in Radiology . Elsevier Health Sciences. ISBN 9781455711444. 
  11. Laurence Knott. Generalised Lymphadenopathy. Patient UK. Retrieved on 2017-03-04. Last checked: 24 March 2014
  12. "Lymphadenopathy and malignancy ". American Family Physician 66 (11): 2103–10. December 2002. PMID 12484692. 
  13. 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. 
  14. 14.0 14.1 Weiss, Lawrence M; O'Malley, Dennis (2013). "Benign lymphadenopathies ". Modern Pathology 26 (S1): S88–S96. doi:10.1038/modpathol.2012.176. ISSN 0893-3952.