Clinical presentation and treatment of hyperthyroidism associated with thyroid cancer.

Objective: Hyperthyroidism apparently does not protect the patients from thyroid cancer as believed before. In contrast, hyperthyroidism with concurrent thyroid cancer can be diagnosed after pathological examination of unsuspect nodules. The aim of this study was to evaluate the coexistence of hyperthyroidism and thyroid carcinoma and to discuss the advantages of total thyroidectomy in such cases.
Methods: Between January 2002 and October 2004, 120 hyperthyroid patients underwent surgical treatment in our clinic. All patients with hyperthyroidism in this study underwent fine-needle aspiration biopsy and cytologic examination. Frozen section evaluation was performed in all of these patients during the operation.
Results: Among these patients 10 had concurrent thyroid cancer. Only one of these patients was examined by fine needle aspiration biopsy prior to operation, while the rest of malignancies was diagnosed from unsuspect nodules.
Conclusions: The selection of appropriate operation procedure appears very important to find out and treat concurrent thyroid cancers. We diagnosed 90 % of thyroid cancers incidentally. If there are no technical difficulties, we prefer total thyroidectomy for the patients with toxic multinodular goiter and Graves' disease with nodules.