Is the thyorid malignancy associated with hyperthyroidism really so rare?

To appraise the risk of associated malignancy in patients designed for radioiodine therapy ultrasound guided fine needle biopsy of scintigraphically hot and representative cold nodules was performed in 102 hyperthyroid patients. The average patients' age was 64±11 years. 99mTc-pertechnetate and 131I scans, showed similar distribution of radioactivity: 44 solitary, 26 double and 32 multiple hot spots were delineated. Among them 138 nodules were examined. Cytologically atypism was found in four patients (3.9%). Two of these patients had follicular carcinomas, verified histologically and two suspect Huerthle cell tumors. Conclusion: because of significant incidence of malignancy in the autonomous goiter, fine needle biopsy is warranted in every patients before radioiodine therapy in all nodules irrespective of their scintigraphic or acoustic characteristics before radioiodine therapy. (orig.)