LONG-TERM CHANGES IN NODULAR GOITER - A 5-YEAR PROSPECTIVE RANDOMIZEDTRIAL OF LEVOTHYROXINE SUPPRESSIVE THERAPY FOR BENIGN COLD THYROID-NODULES

We studied for 5 yr a homogeneous group of 83 patients randomly assign ed to a levothyroxine (L-T-4) suppressive therapy or to a control grou p to evaluate changes in nodule or thyroid size, appearance of new nod ules, and correlations with clinical parameters. In the control group, mean nodule volume increased significantly after 5 yr (2.12 +/- 1.46 us. 1.46 +/- 0.77 mt), whereas in the treatment group it decreased, al though not significantly (1.45 +/- 1.17 mt vs. 1.53 +/- 0.61 mt). Base line nodule volume was not different in the two groups, but a signific ant difference was observed at 5 yr. After 5 yr, sonograms detected 12 new nodules in the control group (28.5%) and 3 (7.5%) in the treatmen t group. Nodule shrinkage was more frequent in patients with complete TSH suppression, but no correlation was found with other parameters. A significant increase in thyroid size was observed in the control grou p. In conclusion, long term TSH suppression induced volume reduction i n only a subgroup of thyroid nodules, but effectively prevented the ap pearance of new lesions and increases in nodule and thyroid volume. As the changes in the natural history of nodular goiter are related to p rolonged TSH suppression, which can induce unfavorable side-effects, L -T-4 suppressive therapy should be reserved for small nodules in young er patients.