Prof Ahmed M Badheeb

Professor of Medical Oncology & internal Medicine

Badheebdr@gmail.com

Hürthle cells: benign or malignant?

A monomorphous cell population of

Hürthle cells arranged in loosely

cohesive clusters and single cells. The

cells are polyhedral and have abundant

granular cytoplasm with well-defined

cell borders. The nuclei are enlarged

and have a central prominent

macronucleolus.Some investigators

believe that this condition is distinct

from other follicular cell neoplasms.

Hürthle cells are observed in both

neoplastic and nonneoplastic

conditions of the thyroid gland

(eg, Hashimoto thyroiditis, nodular

and toxic goiter).

Oncocytic cells in the thyroid are often called Hürthle cells

Hürthle cell carcinoma of the thyroid

• It is rare

• 3-10% of all differentiated thyroid cancers

• WHO: variant of follicular ( follicular

carcinoma, oxyphilic)

Hürthle cells are also found in other tissues

• salivary gland

• Parathyroid gland

• Esophagus

• Pharynx

• Larynx

• trachea

• Kidney

• Pituitary

• Liver

Controversy exists about the origin of Hürthle cells, which generally are thought to derive from the follicular epithelium.

A Hürthle cell adenoma or CA ?

FNA : useless is based on:

• vascular or capsular invasion• Extra-thyroidal spread & lymph node & systemic mets.

A Hürthle cell CA : Behavior

• 33% mets potential

• More aggressive than follicular

• overall mortality rates ranging from 9-28%.

A Hürthle cell CA : predictors of adverse outcome

• invasion

• Tumor size> 4cm

• extrathyroidal extension

• Initial nodal or distant mets

Hürthle cell cancer : the highest incidence of metastasis

• Hürthle cell cancer has the highest incidence of metastasis among the

differentiated thyroid cancers. Metastatic disease is reported at the time of

initial diagnosis in 10-20% of patients and in 34% of the patients overall.

• Metastasis usually occurs hematogenously (RET negative)

• The lungs, bones, and CNS are the most prevalent sites of metastases.

• Local spread ( RET +ve)

• papillary variant of Hürthle cell cancer (ie, Hürthle cell papillary thyroid CA

A Hürthle cell CA : Management

• Excision (total if invasive ,mets, pt’s

preferences)

• Postop iodine-131 scan (4-6 weeks post-op)

• No thyroid hormone in the interim.

• If uptake occurs, a treatment dose of iodine-131 (131 I) is administered, and another total body scan is obtained 4-7 days later.

A Hürthle cell CA : 131 iodine • Hürthle cell cancer has a lower avidity for131 I;

• ~10% of mets take up radioiodine, compared with 75% of follicular

mets ;

• Followed by thyroxin