This document discusses Hürthle cells and Hürthle cell carcinoma of the thyroid gland. It notes that Hürthle cells can be found in both benign and malignant thyroid conditions. Hürthle cell carcinoma accounts for 3-10% of differentiated thyroid cancers. It has a higher risk of metastasis than other differentiated thyroid cancers, with metastatic disease found in 10-20% of patients at diagnosis and 34% overall. Management of Hürthle cell carcinoma involves surgical excision followed by iodine-131 scanning and potentially radioactive iodine treatment, though the cancer has lower avidity for iodine than other differentiated thyroid cancers.

1. Prof Ahmed M Badheeb
Professor of Medical Oncology & internal Medicine
Badheebdr@gmail.com

2. 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

3. Hürthle cell carcinoma of the thyroid
• It is rare
• 3-10% of all differentiated thyroid cancers
• WHO: variant of follicular ( follicular
carcinoma, oxyphilic)

4. 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.

5. A Hürthle cell adenoma or CA ?
FNA : useless
is based on:
• vascular or capsular invasion
• Extra-thyroidal spread & lymph node & systemic mets.

6. A Hürthle cell CA : Behavior
• 33% mets potential
• More aggressive than follicular
• overall mortality rates ranging from 9-28%.

7. A Hürthle cell CA : predictors of adverse outcome
•
•
•
•
invasion
Tumor size> 4cm
extrathyroidal extension
Initial nodal or distant mets

8. 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

9. 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.

10. A Hürthle cell CA : 131 iodine
lower avidity for131 I;
•
Hürthle cell cancer has a
•
~10% of mets take up radioiodine, compared with 75% of follicular
mets ;
• Followed by thyroxin