Amiodarone-induced thyrotoxicosis with thyroid papillary cancer in multinodular goiter: case report.

Objective: To report a case of amiodarone-induced thyrotoxicosis (AIT) concomitant with thyroid cancer in multinodular goiter (MNG). Clinical Presentation and Intervention: A 61-year-old man treated with amiodarone for 5 years presented with mild sweating. He was found to have AIT simultaneously with thyroid papillary cancer and MNG. Administration of amiodarone was stopped, and he was treated with methimazole for AIT. Five weeks after the initial treatment, thyroid function normalized. Total thyroidectomy was considered to enable use of amiodarone again. Conclusion: This case showed that thyrotoxicosis, MNG and amiodarone may contribute to thyroid carcinogenesis. Amiodarone should be carefully commenced in cases with MNG.