Thyroid cancer with concurrent hyperthyroidism

Objective: To study the clinical manifestation, outcome, and factors predicting metastases in patients with thyroid cancer and concurrent hyperthyroidism. Design: Retrospective study of 37 thyrotoxic patients with differentiated carcinomas of the thyroid who were operated on between 1979 and 1995. The follow-up period ranged from 562 days to 14 years 9 months (mean ± SE, 2093 ± 201 days). Setting: University hospital with an annual performance rate of about 700 thyroid operations. Patients: Thyroidectomy was performed in 37 patients (31 women and 6 men), including 33 papillary carcinomas and 4 follicular carcinomas. The mean ± SE age of the patients was 38.6 ± 2.2 years. Results: The mean ± SE diameter of tumors was 13.2 ± 0.9 mm (range, 2-67 mm). The tumor size in 25 patients (68%) was 10 mm or smaller. Subtotal thyroidectomy (21 patients), total thyroidectomy (8 patients), near-total thyroidectomy (4 patients), and completion thyroidectomy (4 patients) were performed. Twenty-eight patients underwent postoperative sodium iodide 1131 (¹³¹I ablation for thyroid remnant. There was 1 local recurrence, 3 metastases to regional neck lymph nodes, and 3 distant metastases. A patient with follicular carcinoma died of metastases at 3 years 4 months after thyroidectomy. Age, sex, duration of thyrotoxic symptoms, tumor size, histopathological findings, type of goiter, extent of surgery, ¹³¹I ablation, and 6-week postoperative serum concentrations of thyroglobulin or thyrotropin were not significant factors in predicting metastases. Serum levels of triiodothyronine and thyroxine before antithyroid treatment in the patients with metastases were significantly higher than in those without metastases. Conclusion: The majority of patients with thyroid cancer and concurrent hyperthyroidism have small carcinomas.