Amiodarone-induced thyrotoxicosis and thyroid cancer: clinical, immunohistochemical, and molecular genetic studies of a case and review of the literature.

Amiodarone-induced thyrotoxicosis (AIT) is a well-known complication of amiodarone treatment found in 3% to 12% of patients. Two types of AIT have been described, each associated with a distinct histologic pattern of thyroid involvement. Type 1, which typically develops in the background of pre-existing thyroid disease, is due to iodine-induced excess thyroid hormone synthesis, whereas type 2 is due to destructive thyroiditis. The prevalence of thyroid cancer in patients with AIT is unknown. We report a case of papillary thyroid carcinoma associated with type 2 AIT.