ABSTRACT
OBJECTIVE: The purpose of this study was to clarify the efficacy of radioiodine (RI) therapy in Japanese patients with autonomously functioning thyroid nodules (AFTNs). METHODS: We performed a retrospective analysis to assess the management of AFTN patients. Thyroid lobectomy was performed to treat toxic adenoma (TA) patients, and total thyroidectomy to treat toxic multinodular goiter (TMNG) patients. RI therapy was administered in the form of a single dose (500 MBq) of isotope in the outpatient clinic. Percutaneous ethanol injection therapy (PEIT) was performed under ultrasound guidance. RESULTS: Of the total 205 patients, consisting of 159 TA and 46 TMNG patients, 99 underwent surgery, 50 received RI therapy, and 56 received PEIT. Remission of thyrotoxicosis was achieved in all of the patients who were treated surgically. Hypothyroidism was documented in six of the 72 patients who were treated surgically other than by total thyroidectomy. Remission of thyrotoxicosis was observed in 43 of the 50 patients who were treated by RI therapy. Nine TA patients developed hypothyroidism during the follow-up period after RI therapy. Several PEIT sessions were required to achieve a remission of thyrotoxicosis. Remission of thyrotoxicosis was achieved in 29 of the 56 patients treated by PEIT, and thyrotoxicosis recurred in 17 these 56 patients. CONCLUSION: Surgery is the treatment of choice for large nodules and nodules that are resistant to other treatments, because it allows prompt control of thyrotoxicosis. RI therapy is a safe and effective means of controlling thyrotoxicosis in AFTN patients. We conclude that RI therapy is the treatment of choice for definitive treatment of AFTN patients who do not have local compression symptoms.
