Thyroid gland
The thyroid gland is an important little endocrine organ in the anterior neck. It is frequently afflicted by cancer... but the common cancer has such a good prognosis there is debate about how aggressively it should be treated. The cytopathology of the thyroid gland is dealt with in the thyroid cytology article.
The gland frustrates a significant number of pathologists, as the criteria for cancer are considered a bit wishy-washy.
Thyroid specimens
They come in three common varieties
- FNA (fine needle aspiration).
- Done to triage patients/rule-out malignancy - discussed in the article thyroid cytopathology.
- Hemithyroid.
- Done to get a definitive diagnosis.
- May be a "completion" - removal of the other half following definitive diagnosis.
- Total thyroid.
- Done for malignancy or follicular lesion.
Gross pathology
- White nodules - think:
- Lymphoid tissue.
- Papillary thyroid carcinoma - may be calcified.[1]
Diagnoses
Common
- Nodular hyperplasia -- most common.
- Lymphocytic thyroiditis.
- Papillary thyroid carcinoma (PTC) -- most common cancer.
- Parathyroid tissue.
Pitfalls/weird stuff
- Thyroid tissue lateral to the jugular vein (often referred to as lateral aberrant thyroid tissue) is generally considered metastatic thyroid carcinoma (papillary thyroid carcinoma) even if it looks benign.[2]
- This dictum is disputed.[3]
- The level VI and VII lymph nodes are medial to the jugular.
- Hashimoto's disease may have so many lymphocytes that it mimics a lymph node -- may lead to misdiagnosis of PTC.
- Parasitic nodule: clump of thyroid that is attached by a thin thread... but looks like a separate nodule; may lead to misdiagnosis of PTC.
Image:
Diagnostic keys
The following should prompt careful examination:[5]
- Architecture: microfollicular, trabecular, solid, insular.
- Thick capsule.
- Necrosis - rare in the thyroid.
Thyroid IHC - general comments
- Not really useful.
- Papers with very small sample sizes abound.
Follicular thyroid carcinoma vs. papillary thyroid carcinoma
- CD31 more frequently positive in follicular lesions.[6]
- CD31 is a marker for microvessel density.
- Galectin-3 thought to be positive in papillary carcinoma.[6]
- HBME-1 thought to be positive in papillary lesions.[7]
Thyroid lesions per WHO
- Adapted from the Washington Manual of Surgical Pathology.[8]
Adenoma
- Follicular adenoma.
- Hyalinizing trabecular tumour.
Carcinoma
- Papillary carcinoma.
- Follicular carinoma.
- Medullary carcinoma.
- Undifferentiated (anaplastic) carcinoma.
- Poorly differentiated carcinoma.
- Squamous cell carcinoma.
- Mucoepidermoid carcinoma.
- Sclerosing mucoepidermoid carcinoma with eosinophilia.
- Mucinous carcinoma.
- Mixed medullary and follicular carinoma.
- Spindle cell tumour with thymus-like differentiation.
- Carcinoma showing thymus-like differentiation.
Others
- Teratoma.
- Lymphoma.
- Ectopic thymoma.
- Angiosarcoma + other soft tissue lesions.
- Paraganglioma.
- Solitary fibrous tumour.
- Follicular dendritic cell tumour.
- Langerhans cell histiocytosis.
- Metastasis.
Parathyroid glands
- May make an appearance in the context of thyroid surgery.
Benign
Solid cell nest of the thyroid gland
- AKA solid cell nest of thyroid.
General
- Embryonic remnants endodermal origin.[9]
- Incidental finding.
Note:
- Hypothesized to have some relation to mucoepidermoid carcinoma of the thyroid gland;[10] however, another study suspects a relationship with papillary thyroid carcinoma.[11]
Microscopic
Features:[9]
- Cellular solid or cystic cluster of variable size with:
- Cuboidal cellular morphology.
- May have columnar morphology.
- Moderate-to-scant eosinophilic cytoplasm.
- Round/ovoid nuclei with finely granular chromatin.
- Cuboidal cellular morphology.
- +/-Goblet cells (~30% of cases).[12]
DDx:[9]
- C-cell hyperplasia.
- Medullary carcinoma.
- Squamous lesions.
Images
www:
IHC
Features:[9]
- p63 +ve.
- -ve in clear cells.
- CEA +ve (polyconal).[12]
- +ve also in clear cells.
- Chromogranin A +ve ~45% of cases.[12]
Sign out
Solid cell nests of the thyroid gland are usually not reported.
Thyroid gland nodular hyperplasia
- AKA nodular hyperplasia.
- AKA adenomatoid nodule.
Follicular thyroid adenoma
Graves disease
Idiopathic granulomatous thyroiditis
- AKA granulomatous thyroiditis - non-specific term; granulomas may be due a number of causes.
- AKA subacute thyroiditis.
- AKA de Quervain thyroiditis.
- Should not be confused with de Quervain's disease (AKA gamer's thumb) something completely unrelated to the thyroid.
General
- Women > men.
- Etiology: possibly viral.[13]
Clinical:
- Tenderness.[14]
Management:
- Medical.
- Rarely surgery.[15]
Microscopic
- Granulomas with multinucleated giant cells - usu. with engulfed colloid.
- Lymphocytes.
- Plasma cells.
- +/-Fibrosis.
DDx:
- Infectious granulomatous disease (fungal, microbacterial).
- Palpation thyroiditis.
- Sarcoidosis (classically intrafollicular distribution).
Images
Stains
- ZN -ve.
- GMS -ve.
Palpation thyroiditis
General
- Granulomatous inflammation due to palpation.
- Incidence of granulomas higher in surgical thyroid specimens than autopsies.[13]
Microscopic
Features:[13]
- Granulomas involving the follicle.
- Histiocytes within the colloid.
DDx:
- Idiopathic granulomatous thyroiditis.
- Sarcoidosis.
- Infectious granulomatous thyroiditis.
Stains
- ZN -ve.
- GMS -ve.
Riedel thyroiditis
General
Clinical features:[17]
- Extremely rare.
- Women > men.
- Usually smokers.
- May be associated with retroperitoneal fibrosis.
- May be hypothyroid.
- +/-Obstructive symptoms.
Microscopic
Features:
- Fibrosis.
- Specimen often fragmented as it was difficult to remove.
DDx:
- Anaplastic carcinoma, spindle cell variant.
Hashimoto thyroiditis
General
- This is a clinical diagnosis.
- The histomorphologic findings, generally, are not diagnostic.
Etiology:
- Autoimmune disease leading to hypothyroidism.
- Often genetic/part of a syndrome.
Clinical
Serology:[18]
- Antimicrosomal (antithyroid peroxidase) +ve.
- Antithyroglobulin +ve.
- Normal: <4.0 IU/mL.[19]
Associated pathology:[18]
- Increased risk of B-cell lymphoma; these are classically:[20]
- MALT lymphoma.
- Diffuse large B cell lymphoma (DLBCL).
Microscopic
Features:
- Lymphocytic infiltrate - key feature.
- Nuclear clearing common.
- May confuse with papillary thyroid carcinoma.
- Polymorphous lymphoplasmacytic infiltrate with germinal centres.[21]
- +/-Oncocytic metaplasia.
Notes:
- Histologically often not possible to separate from "non-specific" thyroiditis.[22]
DDx:
IHC
- Panel to exclude lymphoma may be required, e.g. CD3, CD20, CD10, BCL6, BCL2, kappa, lambda.
Molecular
- Occasionally done to exclude lymphoma - see MALT lymphoma and DLBCL.
C-cell hyperplasia
- Abbreviated CCH.
Malignant neoplasm
There are a bunch of 'em. The most common, by far, is papillary.
Papillary thyroid carcinoma
- Abbreviated PTC.
Insular carcinoma
Follicular thyroid carcinoma
- AKA follicular carcinoma.
Medullary thyroid carcinoma
- Abbreviated MTC.
Poorly differentiated thyroid carcinoma
Anaplastic thyroid carcinoma
Lymphomas of the thyroid
General
- Rare.
- Increased risk with chronic inflammatory conditions.
- Fit in the the greater category of MALT lymphoma.
Microscopic
Features:
- Lymphoepithelial lesion - key feature.
- Plasma cells.
- "Overgrowth" - thyroid parenchyma displaced by lymphocytes.
Weird stuff
Hyalinizing trabecular tumour
- AKA hyalinizing trabecular adenoma.
- Abbreviated HTT.
General
- Considered by some (e.g. Silvia Asa) to be a variant of papillary thyroid carcinoma.[23]
- Behaviour similar to papillary thyroid carcinoma - indolent.
Microscopic
Features:
- Trabecular arrangement of cells.
- May have "curved" trabeculae.
- Extracellular space has hyaline material - key feature.
- Cytoplasm mimics hyaline material in the extracellular space.
DDx:
- Papillary thyroid carcinoma (if one believes this is a separate entity).
- Medullary thyroid carcinoma - not trabecular, nuclei not PTC-like.
- Paraganglioma.[24]
Images
www:
IHC
- Thyroglobulin +ve.
- NSE +ve.
Hürthle cell neoplasm
- AKA oncocytic neoplasm.
- Also spelled Hurthle cell neoplasm.
General
- Incidence: uncommon.
- This is a general category - includes:
- Hürthle cell adenoma.
- Hürthle cell carcinoma.
- Some advocate total thyroidectomy for all Hürthle cell neoplasms, as it is difficult to reliably differentiate adenomas and carcinomas.[27]
- It can be understood as a special type of follicular neoplasm (including follicular thyroid adenoma and follicular thyroid carcinoma).[28]
Adenoma vs. carcinoma
Suggestive for carcinoma:[27]
- Male.
- >4 cm
- Adenomas usu. <3 cm.
Definite for carcinoma:[27]
- Lymphovascular invasion.
- Capsular invasion.
Gross
- Yellow.
- Encapsulated.
Microscopic
Features:[28]
- Oncocytes >= 75% of cells:
- Abundant granular, eosinophilic cytoplasm.
- Round regular nucleus +/- prominent nucleolus.
- +/-Degenerative changes.
Negatives:
- Lack nuclear features of papillary thyroid carcinoma.
- Lack features of medullary thyroid carcinoma.
DDx:[29]
- Papillary thyroid carcinoma oncocytic variant.
- Medullary thyroid carcinoma oncocytic variant.
- Others.
Minocycline associated thyroid pigmentation
- AKA minocycline thyroid.
General
- Benign pigmentation of the thyroid due to minocycline, an antibiotic.
- Reported at other sites, e.g. heart valves,[30] skin,[31] coronary arteries.
Gross
- Black thyroid.[32]
Images:
- Pigmented thyroid gland (rheumatology.org).
- Minocycline thyroid - gross and microscopic (archivesofpathology.org).[33]
Microscopic
Features:
- Granular yellow blobs:
- Location:
- Intracytoplasmic in the follicule-lining cells, i.e. follicular cells.
- Intrafollicular.
- Variable size ~0.5-4 micrometers.
- Location:
Notes:
- Pigment described as lipofuscin-like.[34]
Images
Stains
See also
References
- ↑ BEC. 20 October 2009.
- ↑ JOHNSON, RW.; SAHA, NC. (Jun 1962). "The so-called lateral aberrant thyroid.". Br Med J 1 (5293): 1668-9. PMC 1958877. PMID 14452106. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1958877/.
- ↑ Escofet, X.; Khan, AZ.; Mazarani, W.; Woods, WG. (Jan 2007). "Lessons to be learned: a case study approach. Lateral aberrant thyroid tissue: is it always malignant?". J R Soc Promot Health 127 (1): 45-6. PMID 17319317.
- ↑ URL: http://radiopaedia.org/articles/lymph-node-levels-of-the-neck. Accessed on: 5 November 2012.
- ↑ SR. 17 January 2011.
- ↑ 6.0 6.1 Rydlova, M.; Ludvikova, M.; Stankova, I. (Jun 2008). "Potential diagnostic markers in nodular lesions of the thyroid gland: an immunohistochemical study.". Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 152 (1): 53-9. PMID 18795075.
- ↑ Papotti, M.; Rodriguez, J.; De Pompa, R.; Bartolazzi, A.; Rosai, J. (Apr 2005). "Galectin-3 and HBME-1 expression in well-differentiated thyroid tumors with follicular architecture of uncertain malignant potential.". Mod Pathol 18 (4): 541-6. doi:10.1038/modpathol.3800321. PMID 15529186.
- ↑ Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 331. ISBN 978-0781765275.
- ↑ 9.0 9.1 9.2 9.3 Reis-Filho JS, Preto A, Soares P, Ricardo S, Cameselle-Teijeiro J, Sobrinho-Simões M (January 2003). "p63 expression in solid cell nests of the thyroid: further evidence for a stem cell origin". Mod. Pathol. 16 (1): 43–8. doi:10.1097/01.MP.0000047306.72278.39. PMID 12527712. http://www.nature.com/modpathol/journal/v16/n1/full/3880708a.html.
- ↑ Ozaki, O.; Ito, K.; Sugino, K.; Yasuda, K.; Yamashita, T.; Toshima, K.. "Solid cell nests of the thyroid gland: precursor of mucoepidermoid carcinoma?". World J Surg 16 (4): 685-8; discussion 688-9. PMID 1413837.
- ↑ Prichard, RS.; Lee, JC.; Gill, AJ.; Sywak, MS.; Fingleton, L.; Robinson, BG.; Sidhu, SB.; Delbridge, LW. (Feb 2012). "Mucoepidermoid carcinoma of the thyroid: a report of three cases and postulated histogenesis.". Thyroid 22 (2): 205-9. doi:10.1089/thy.2011.0276. PMID 22224821.
- ↑ 12.0 12.1 12.2 Mizukami Y, Nonomura A, Michigishi T, et al. (February 1994). "Solid cell nests of the thyroid. A histologic and immunohistochemical study". Am. J. Clin. Pathol. 101 (2): 186–91. PMID 7509563.
- ↑ 13.0 13.1 13.2 13.3 Lloyd, Ricardo V. (2002). Endocrine Diseases (AFIP Atlas of Nontumor Pathology). Toronto: American Registry of Pathology. ISBN 978-1881041733. http://www.amazon.com/Endocrine-Diseases-Atlas-Nontumer-Pathology/dp/1881041735.
- ↑ Szczepanek-Parulska, E.; Zybek, A.; Biczysko, M.; Majewski, P.; Ruchała, M. (2012). "What might cause pain in the thyroid gland? Report of a patient with subacute thyroiditis of atypical presentation.". Endokrynol Pol 63 (2): 138-42. PMID 22538753.
- ↑ Volpé, R. (1993). "The management of subacute (DeQuervain's) thyroiditis.". Thyroid 3 (3): 253-5. PMID 8257868.
- ↑ Mills, Stacey E; Carter, Darryl; Greenson, Joel K; Oberman, Harold A; Reuter, Victor E (2004). Sternberg's Diagnostic Surgical Pathology (4th ed.). Lippincott Williams & Wilkins. pp. 559. ISBN 978-0781740517.
- ↑ 17.0 17.1 Fatourechi, MM.; Hay, ID.; McIver, B.; Sebo, TJ.; Fatourechi, V. (Jul 2011). "Invasive fibrous thyroiditis (Riedel thyroiditis): the Mayo Clinic experience, 1976-2008.". Thyroid 21 (7): 765-72. doi:10.1089/thy.2010.0453. PMID 21568724.
- ↑ 18.0 18.1 Poropatich C, Marcus D, Oertel YC (1994). "Hashimoto's thyroiditis: fine-needle aspirations of 50 asymptomatic cases". Diagn. Cytopathol. 11 (2): 141–5. PMID 7813361. http://www3.interscience.wiley.com/journal/112701408/abstract?CRETRY=1&SRETRY=0.
- ↑ URL: http://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpretive/84382. Accessed on: 15 October 2015.
- ↑ Ohye, H.; Fukata, S.; Hirokawa, M. (Nov 2007). "[Malignant lymphoma of the thyroid].". Nihon Rinsho 65 (11): 2092-8. PMID 18018576.
- ↑ Lefkowitch, Jay H. (2006). Anatomic Pathology Board Review (1st ed.). Saunders. pp. 672. ISBN 978-1416025887.
- ↑ Mills, Stacey E; Carter, Darryl; Greenson, Joel K; Oberman, Harold A; Reuter, Victor E (2004). Sternberg's Diagnostic Surgical Pathology (4th ed.). Lippincott Williams & Wilkins. pp. 560. ISBN 978-0781740517.
- ↑ Cheung CC, Boerner SL, MacMillan CM, Ramyar L, Asa SL (December 2000). "Hyalinizing trabecular tumor of the thyroid: a variant of papillary carcinoma proved by molecular genetics". Am. J. Surg. Pathol. 24 (12): 1622–6. PMID 11117782.
- ↑ URL: http://path.upmc.edu/cases/case465/dx.html. Accessed on: 17 January 2011.
- ↑ Baloch, ZW.; Puttaswamy, K.; Brose, M.; LiVolsi, VA. (2006). "Lack of BRAF mutations in hyalinizing trabecular neoplasm.". Cytojournal 3: 17. doi:10.1186/1742-6413-3-17. PMID 16867191.
- ↑ URL: http://www.ispub.com/journal/the-internet-journal-of-endocrinology/volume-2-number-1/hyalinizing-trabecular-neoplasm-of-the-thyroid-controversies-in-management.html. Accessed on: 1 January 2012.
- ↑ 27.0 27.1 27.2 Wasvary, H.; Czako, P.; Poulik, J.; Lucas, R. (Aug 1998). "Unilateral lobectomy for Hurthle cell adenoma.". Am Surg 64 (8): 729-32; discussion 732-3. PMID 9697901.
- ↑ 28.0 28.1 Thompson, Lester D. R. (2006). Endocrine Pathology: A Volume in Foundations in Diagnostic Pathology Series (1st ed.). Churchill Livingstone. pp. 104. ISBN 978-0443066856.
- ↑ Montone KT, Baloch ZW, LiVolsi VA (August 2008). "The thyroid Hürthle (oncocytic) cell and its associated pathologic conditions: a surgical pathology and cytopathology review". Arch. Pathol. Lab. Med. 132 (8): 1241–50. PMID 18684023.
- ↑ 30.0 30.1 Sant'Ambrogio, S.; Connelly, J.; DiMaio, D.. "Minocycline pigmentation of heart valves.". Cardiovasc Pathol 8 (6): 329-32. PMID 10615019.
- ↑ Geria AN, Tajirian AL, Kihiczak G, Schwartz RA (2009). "Minocycline-induced skin pigmentation: an update". Acta Dermatovenerol Croat 17 (2): 123–6. PMID 19595269.
- ↑ Noble, JG.; Christmas, TJ.; Chapple, C.; Katz, D.; Milroy, EJ. (Jan 1989). "The black thyroid: an unusual finding during neck exploration.". Postgrad Med J 65 (759): 34-5. PMC 2429157. PMID 2780449. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2429157/.
- ↑ 33.0 33.1 Raghavan, R.; Snyder, WH.; Sharma, S. (Mar 2004). "Pathologic quiz case: tumor in pigmented thyroid gland in a young man. Papillary thyroid carcinoma in a minocycline-induced, diffusely pigmented thyroid gland.". Arch Pathol Lab Med 128 (3): 355-6. doi:10.1043/1543-2165(2004)128355:PQCTIP2.0.CO;2. PMID 14987144.
- ↑ Gordon, G.; Sparano, BM.; Kramer, AW.; Kelly, RG.; Iatropoulos, MJ. (Oct 1984). "Thyroid gland pigmentation and minocycline therapy.". Am J Pathol 117 (1): 98-109. PMC 1900569. PMID 6435454. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1900569/.