Diagnosis and management of large toxic multinodular goiters.

Toxic multinodular goiters, estimated weight 100 g or more, occurred in 35 patients between 1961 and 1984. All but two were older than 50; 32 were females. Twenty had goiters of 100-130 g; four of 140-200 g; and 11 were massive. Radioiodine uptakes were 30% or less for 22. Seven of 17 with both T4 and T3 data had T4 toxicosis. Thirty-two patients received radioiodine therapy, delivering 200 microCi per gram when possible. Doses were 25-30 mCi for 17 patients; 50-100 mCi for 12 patients, and 150-200 mCi for three patients. Hyperthyroidism was eliminated with one dose in 25 patients (78%); five patients required two doses. Twenty-two patients were euthyroid after radioiodine; 25 of 28 had persistent goiters. Two patients were treated successfully surgically. One refused surgery and radioiodine, and has been maintained on antithyroid drugs for 10 yr. Two patients died within a few months of an unsuccessful initial dose of radioiodine. Large dose radioiodine therapy is simple, safe, and effective for most patients with large toxic multinodular goiters.