Is routine thyroxine treatment to hinder postoperative recurrence of nontoxic goiter justified?

Previous reports regarding the efficacy of levo-T4 (L-T4) in preventing postoperative recurrence of nontoxic goiter have been controversial. This study was designed to evaluate the influence of long-term L-T4 treatment on thyroid volume after thyroidectomy for nontoxic goiter. We studied 202 consecutive patients operated on for benign nontoxic goiter and followed them for a minimum of 12 months (median, 10 yr; range, 1-14 yr). Three months after thyroidectomy, patients were randomized to L-T4 treatment (group A, n = 100) with an initial dose of 150 microg daily and to no treatment (group B, n = 102). All were clinically and biochemically euthyroid, and preoperatively none were taking any thyroid and/or antithyroid medication. Standard thyroid function variables and ultrasonically determined thyroid volume (normal range, 9-28 mL) were determined before and 3 and 12 months after randomization and yearly thereafter. Recurrence was defined as an ultrasonically enlarged thyroid gland. Clinical data were similar between the two groups. Incidence of recurrence in group A was 19/100 (21%; 95% CL 0-42%; life-table analysis) and in group B 27/102 (35%; CL 7-64%) (P = 0.16) and was related to removed amount, remnant size, and pathoanatomical diagnosis but not type of operation or postoperative level of serum TSH and T4. L-T4 dose had to be reduced in 36 of 100 patients because of side effects of the treatment. In conclusion, the possible benefits of L-T4 treatment should be weighed against the possible side effects. Our study does not support the routine postoperative use of L-T4.