Thyroid gland
Other thyroid carcinoma
Hurthle cell (oncocytic) tumors

Author: Shahidul Islam, M.D., Ph.D. (see Authors page)

Revised: 26 October 2016, last major update March 2009

Copyright: (c) 2002-2016, PathologyOutlines.com, Inc.

PubMed Search: Hurthle cell [title]

Cite this page: Hurthle cell (oncocytic) tumors. PathologyOutlines.com website. http://pathologyoutlines.com/topic/thyroidhurthle.html. Accessed December 8th, 2016.
Definition / General
  • Follicular neoplasm in which 75% or more of follicular cells have oncocytic features and no chronic thyroiditis is present
  • Hurthle cells / oncocytes by themselves are nonspecific, and are seen in Hashimoto’s thyroiditis and other neoplasms
  • Tend to infarct after fine needle aspiration
  • Size is predictive; 2 cm or less - almost always adenoma; 6 cm or more - almost always carcinoma (World J Surg 2008;32:702)
  • Malignant if capsular or vascular invasion

Minimally invasive Hurthle cell carcinoma
  • 14% recur, recurrence associated with 4+ foci of vascular invasion, mitotic figures and solid/trabecular growth pattern (Cancer 2006;106:1669)
Terminology
Minimally invasive Hurthle cell carcinoma
  • Also called Encapsulated Hurthle cell carcinoma
Epidemiology
  • Usually adult women
Prognostic Factors
  • Carcinomas have 5 year survival of 60 - 80%, with metastases to lung, bone and regional lymph nodes
  • Poorer prognosis if higher N / C ratio, small cell pattern, p53+ / bcl2- (Am J Surg Pathol 1996;20:686); also metastatic lymph nodes or other metastases, high stage (Eur J Surg Oncol 2009;35:230)
Case Reports
Treatment
  • Adenomas are cured by excision
Gross Description
  • Solid, tan, encapsulated, lobulated, well vascularized
  • Invasion into adjacent tissue not apparent
Gross Images

Images hosted on PathOut server:
AFIP images

Adenoma with massive infarct

Carcinoma has focal capsular invasion

Carcinoma, courtesy of Mark R. Wick, M.D.

Micro Description
  • At least 75% of follicular cells are oncocytic with large size, distinct cell borders, deeply eosinophilic and granular cytoplasm, large nucleus with prominent nucleolus
  • Follicular, trabecular, solid or papillary growth patterns
  • Large follicles have adjacent fibrovascular septa that resemble papillae when cut tangentially
  • May have inspissated intraluminal colloid with concentric laminations that resemble psammoma bodies, usually in lumina
  • Nuclear atypia common but not anaplasia
  • Rarely has Kaposi-like endothelial proliferation with spindle cells containing plump nuclei and focal nesting pattern, focal red blood cell extravasation, but no mitotic figures; spindle cells positive for CD31 and factor VIII, negative for keratin and thyroglobulin, (Mod Pathol 1998;11:995)
Micro Images

Scroll to see all images:


Images hosted on PathOut server:

Courtesy of Andrey Bychkov, M.D., Ph.D.



Adenoma with atypia, courtesy of Mark R. Wick, M.D.

Carcinoma images courtesy of Mark R. Wick, M.D.



Adenoma (AFIP)

Oncocytic adenoma has follicular pattern

Cytoplasm has fine, homogeneously distributed granularity

Massive infarct due to fine needle biopsy

Pseudo-angiosarcomatous pattern

Well developed papillary growth pattern

Psammoma bodies in follicular lumina



Tumor has hyalinized area near capsule

Tumor has focal cells with large hyperchromatic nuclei

Focal papillary formations



Clear cell change (AFIP):

Sharp demarcation between clear and oncocytic cells

Gradual transition from oncocytic to clear cells

Both patterns exist in same cell



Carcinoma (AFIP)

Capsular invasion

Vascular invasion

Trabecular pattern



Multinodular pattern

Nesting pattern resembles insular carcinoma

Pseudopapillary formations due to tangential sectioning

Pulmonary metastasis of tumor with trabecular growth pattern



Minimally invasive Hurthle cell carcinoma

Fine needle biopsy induced necrosis (AFIP)



Images hosted on Flickr:

Hurthle cell adenoma, courtesy of Grace C. H. Yang, M.D.



Images hosted on other servers:

Psammoma bodies in
Hurthle cell neoplasm (figure 3)



Carcinoma

Capsular invasion

Oncocytes with abundant eosinophilic granular cytoplasm (far right pic is with intraluminal calcifications)

No capsular invasion evident



Tumor in internal jugular vein

Various images

Microfollicles

Cells have eosinophilic cytoplasm and prominent nucleoli

Metastasis to breast



Mixed oncocytic and mucinous secreting carcinoma

Ki-67- mucus secreting carcinoma

p53 - mucus secreting carcinoma



Minimally invasive Hurthle cell carcinoma

Intracapsular vascular invasion

Vascular invasion

Distant metastasis to femur

Cytology Description
  • Highly cellular, 75% or more Hurthle cells (abundant granular cytoplasm, round nuclei, often prominent nucleoli), often discohesive cells, some enlarged and pleomorphic with intracytoplasmic lumina (empty vacuoles with magenta [Diff-Quik] or green [Pap] or no material; also transgressing vessels (capillaries in clusters of Hurthle cells, Arch Pathol Lab Med 2001;125:1031)
  • No / rare colloid, lymphocytes, histiocytes, plasma cells or ordinary follicular cells
  • Cannot definitively diagnose malignancy based on cytologic material (Am J Clin Pathol 1993;100:231, Acta Cytol 2008;52:659) but malignant cases tend to have small or large cell dysplasia, nuclear crowding and discohesive cells (Diagn Cytopathol 2008;36:149)
  • Metastatic tumors may have bland cytologic features (Diagn Cytopathol 2007;35:439)
Cytology Images

Images hosted on Flickr:

Hurthle cell adenoma, 10x Diff-Quik

Hurthle cell adenoma, 2x pap stain

Hurthle cell adenoma, 10x pap stain



Images hosted on other servers:

Various images

Microfollicles of carcinoma

Positive Stains
Electron Microscopy Description
  • Numerous large mitochondria with morphologic abnormalities
Electron Microscopy Images

Images hosted on PathOut server:

Dilated mitochondria have reduced cristae (AFIP)

Carcinoma, courtesy of Mark R. Wick, M.D.

Cytoplasm packed
with large mitochondria
with myelin figures (AFIP)



Images hosted on other servers:

Cytoplasm is packed with mitochondria

Molecular / Cytogenetics Description
Differential Diagnosis
  • Benign thyroid lesions with prominent Hurthle cells: abundant colloid, follicular cells and histiocytes mixed with Hurthle cells
  • Papillary and medullary carcinoma may also have prominent Hurthle cells
Additional References