Hürthle cell carcinoma: a clinicopathological study of thirteen cases.

BACKGROUND: Hürthle cell carcinoma (HCC) of the thyroid is a variant of follicular cancer which has been considered by many as a more aggressive disease than the usual well-differentiated carcinoma of the thyroid.

AIM: To investigate the clinico-pathologic characteristics, treatment and outcome of Hürthle cell carcinoma.

MATERIAL AND METHODS: During a 7-year period, 13 patients (seven male, six female; mean age at diagnosis 48.4+/-13.2 years) with HCC were treated and monitored at the Ankara University. The measured diameter of the tumours varied from 1 to 6 cm in diameter with pathological examination. Three of the HCC had extra thyroid invasion, five had intrathyroid invasion, and five were encapsulated. One of the patients had a history of low-dose external radiation to the head and neck in childhood. Treatment consisted of a total thyroidectomy in 12 patients, and a near total thyroidectomy in one patient. At surgery, lymph node metastases were present in three patients and lymph node dissection were performed in these patients. Distant metastases were detected in only one patient (lung metastasis).

RESULTS: All patients had radioiodine ablation therapy for residual thyroid tissue. Twelve of the 13 patients were ablated with a single dose of 131 I (3.7-5.5 GBq). A second dose of radioiodine therapy was required in only one patient who had lung metastases and this patient is still being followed up. After a median follow-up period of 85 months, there was no recorded mortality due to the disease and 12/13 of the patients were categorized as disease free (criteria for ablation were a negative I whole-body scan and very low serum thyroglobulin levels).

CONCLUSION: We did not find higher incidences of local recurrences, distant metastases or mortality rates compared to well differentiated thyroid carcinomas. HCC of the thyroid and well differentiated thyroid carcinomas have similar biological behaviour. Their treatment should be similar, including total or near-total thyroidectomy plus modified cervical node dissection when there is lymph node involvement. Radioactive iodine therapy and suppressive laevothyroxin therapy should follow.