Radioiodine therapy for multinodular toxic goiter

Abstract

Background: Radiolabeled iodine 131 therapy is used for treatment of multinodular toxic goiter, but long-term follow-up studies are lacking. Methods: A prospective study of 130 consecutive patients (115 women) treated with 131I for multinodular toxic goiter and followed by evaluation of thyroid volume (determined using ultrasound) and thyroid function variables. Results: The patients were observed for a median of 72 months (range, 12-180 months). Sixty-six patients received antithyroid drug pretreatment; 64 did not. Iodine 131 treatment (3.7 MBq/g thyroid tissue corrected to a 100% 24- hour 131I uptake) was given as a single dose in 81 patients, 2 doses in 38, and 3 to 5 doses in 11. One or 2 treatments cured 119 patients (92%), and 68 (52%) became euthyroid within 3 months after 1 131I treatment. The median 131I dose was 370 MBq (range, 93-1850 MBq). Forty-nine patients needing more than 1 131I dose had a reduction in median thyroid volume from 56 mL (range 21-430 mL) to 44 mL (range, 15-108 mL), representing a 24% reduction related to the insufficient 131I dose. In all patients, the initial median thyroid volume of 44 mL (range, 16-430 mL) decreased to 25 mL (range, 8-120 mL) (P