Role of levothyroxine suppressive therapy for benign cold nodules of thyroid: a randomized, double-blind, placebo-controlled clinical trial

Introduction: There is no consensus on the appropriate management of benign cold nodules of the thyroid gland. This study addresses the problem in an iodine-deficient area, evaluating the efficacy of levothyroxine suppression therapy on a 2-year course. Methods: A total of 58 patients affected with benign cold nodules of the thyroid were enrolled. With a double-blind placebo-controlled design, levothyroxine (1.5–2 μg/kg/day) was delivered to the 31 cases over 2 years. The consequences of this treatment were compared with 27 controls. Nodule size was measured with high-resolution ultrasonography. Results: In the treatment group, the mean volume on baseline was 12.8 ± 11.9 ml and changed to 9.4 ± 9.8, 12.4 ± 16.7 and 10.8 ± 9.7 ml in months 6, 12 and 24, respectively. In the placebo group, these figures were 13.0 ± 10.2, 11.5 ± 8.0, 11.7 ± 13.6 and 11.6 ± 8.5 ml, respectively. No significant difference between the two groups was observed. Conclusion: Thyroid-stimulating hormone suppression with levothyroxine for 2 years was not effective in reducing the size of benign cold nodules of the thyroid gland.