PROSPECTIVE, RANDOMIZED, DOUBLE-BLIND-STUDY ABOUT EFFECTIVENESS OF LEVOTHYROXINE SUPPRESSIVE THERAPY IN PREVENTION OF RECURRENCE AFTER OPERATION - RESULT AT THE 3RD YEAR OF FOLLOW-UP

Background. Levothyroxine has often been given to patients operated on for nodular goiter to prevent recurrence. The rationale is that suppr ession of thyroid-stimulating hormone (TSH), considered to be the main growth factor in this disease, can be obtained by administration of l evothyroxine. Methods. Sixty patients undergoing operation for nontoxi c nodular goiter were randomized in two groups: (1) thirty-two were ad ministered levothyroxine at substitutive dosage (100 micrograms) or pl acebo and (2) twenty-eight were given levothyroxine at suppressive dos age (2.2 to 3 mug/kg/day). Levels of thyroid hormones and TSH were eva luated every 6 months. Recurrences detected by echography were then co nsidered. Results. After a 3-year follow-up we observed 25 of 32 recur rences in group 1 and 6 of 28 in group 2 (p < 0.005). Subjects with en demic goiter problems responded better to therapy. Patients with a mul tinodular goiter responded better than patients with a uninodular goit er. No difference was found regarding the type of surgical treatment ( subtotal thyroidectomy vs lobectomy) . Conclusions. The results confir med suppressive therapy as actually being effective in preventing recu rrences at least in iodine-deficient regions like Italy. Thus for thes e patients it may be suggested as a prophylactic treatment after opera tion.