Long-term results of treatment of toxic goiter with radioactive 131I

Abstract

The study included 103 patients with toxic goiter, among whom 75 patients were diagnosed as having Graves' disease (GD) and 28 had thyroid functional autonomy (FA) that was presented with toxic multinodular goiter in most cases. All the patients received ¹³¹I therapy, then they were followed up; the duration of the follow-up of the patients in whom euthyroidism was preserved at the moment this paper was being written was 18 [10; 28] months. The treatment of GD in 86.7% of the cases ended either with hypothyroidlsm (53.4%), recurrent thyrotoxlcosls (33.3%), or with euthyroidism (13.3%). In FA, recurrent thyrotoxlcosls developed statistically less frequently (10.7%; p = 0.041) and a euthyrold state was statistically more frequent (46.4%; p < 0.001). It was concluded that the optimal purpose of ¹³¹I therapy for GD was to destroy the thyroid gland and to achieve persistent hypothyroidlsm, but, in FA, to achieve either euthyroidism or hypothyroidlsm. The use the relatively low activities of ¹³¹I (on the basis of the estimated absorbed dose of 100-200 Gy) was demonstrated to be accompanied by a high (33.33%) risk for recurrent thyrotoxlcosls. The volume of the thyroid gland is the major predictor of the late outcome of ¹³¹I therapy; but the high level of free T₄ after 1 month of ¹³¹I therapy and/or the necessity of temporary use of thyrostatlc therapy Involve a high risk for recurrent thyrotoxlcosis.