Hurthle Cell Carcinoma of the Thyroid
Hurthle Cell Carcinoma of the Thyroid
CASE OF THE MONTH
PRESENTED BY
THE THYROID SURGERY CENTER OF TEXAS, P.A.
1927 Lohmans Crossing Road, Suite 201, Austin, TX 78734
www.thyroidcancer.com
512-608-9595; Fax-512-608-9833
Hurthle Cell Carcinoma of the Thyroid
The patient is a 54 y/o white female referred to The Thyroid Surgery Center of Texas for a very large thyroid gland that was enlarging rapidly and causing significant compression symptoms on both the trachea and esophagus. She was known to be hypothyroid and was taking thyroid hormone supplement. She had been told in Houston that she had Hashimoto's thyroiditis, but her TPO antibodies were negative at that time.
She had undergone a needle biopsy in Houston as well, but as is so often the case it was non-diagnostic, not helpful, and even unnecessary as the patient was going to undergo thyroidectomy regardless of the FNA report. Indeed, the FNA report said only that "the differential diagnosis includes follicular adenoma, well differentiated (encapsulated) follicular carcinoma, follicular variant of papillary carcinoma and cellular adenomatous nodule". This type of "shotgun" differential diagnosis is simply not useful or informative. What's more to the point, not a single Hurthle cell was identified in a Hurthle cell cancer almost the size of a baseball.
A pre-operative ultrasound revealed a 4.1 cm complex mass with some calcification within the thyroid gland. (It grew much larger by the time of her operation). Her thyroglobulin levels were greater than 900; interestingly her thyroglobulin antibodies were positive on one test and negative on yet another.
The patient underwent an uneventful outpatient subtotal thyroidectomy. The frozen section diagnosis at that procedure returned as "follicular cells with extensive Hurthle cell change". The final pathology report, however, called the tumor a Hurthle cell cancer. It was described as minimally invasive and confined to the thyroid, but there were two (2) foci of capsular and lymphovascular invasion. Because of the rarity of Hurthle cancer we sent the slides to Dr. Mario Luna at MD Anderson for evaluation. We have been blessed to have Dr. Luna available to consult with us on our most difficult and unusual thyroid cancer cases for over 30 years now. He confirmed the diagnosis of Hurthle cell Ca and with that information the patient was then scheduled to undergo completion thyroidectomy and bilateral paratracheal and pretracheal lymph node dissection to remove any remaining thyroid tissue or foci of regional metastatic disease.
The accompanying photos demonstrate the patient's surgical procedures. The final pathology report from the second operation showed two (2) remnants of thyroid tissue both of which were negative for tumor but positive for chronic lymphocytic thyroiditis (which is interesting since her pre-operative antibodies for Hashimoto's disease were negative). A total of fourteen (14) lymph nodes were removed in the operative specimen and all were negative for metastatic disease. We did lose some parathyroid tissue, as anticipated, in this aggressive paratracheal lymph node dissection, but I was able to transplant the two superior parathyroid glands into their respective sternocleidomastoid muscles, and the patient has remained normocalcemic since her surgery.
Hurthle cell carcinoma of the thyroid is a disease that requires an aggressive surgical approach, not just because of its propensity to spread to regional lymph nodes (especially paratracheal) but because these tumors, as a rule, do not often uptake 1-131, thus limiting the benefits of this treatment modality for distant disease. Some of these tumors do, however, take up iodine, and for that reason, especially in cases where there is documented lymphatic or vascular invasion, its use should be strongly considered. Notwithstanding costs, the risk/benefit ratio in such cases would strongly lean toward an ablative dose of I-131.
A recent paper out of the University of California San Francisco suggested that there have been only about 400 reported cases of documented Hurthle cell cancer of the thyroid in the last 75 years. Certainly, there have been others but this underscores the rarity of this disease. Our patient will be undergoing 1-131 treatment in the next few weeks and then be seen in virtually indefinite follow up through both our office and the office of her thyroid endocrinologist.
“…Thyroid surgery…it’s all we do…”