Purpose of review: Hyperthyroidism is a commonly encountered clinical issue. Radioactive iodine is one of the treatment modalities employed over the last 80 years. Prior studies are conflicting as to whether radioactive iodine is associated with an increased risk of subsequent malignancy and associated mortality. The present article reviews recent publications on this subject.
Recent findings: Two recent studies make meaningful contributions to the existing literature; however, data remain inconsistent. The first, conducted using the Clalit Health Services database, evaluated solid tumor incidence after radioactive iodine and found no association with increased risk of solid tumor malignancy. The second, which is an updated analysis of the Cooperative Thyrotoxicosis Therapy Follow-up Study, concluded that there is a dose-dependent increased risk of solid tumor mortality using a novel method of estimating organ-specific radiation exposure.
Summary: In patients with hyperthyroidism, radioactive iodine is a popular and effective treatment option. Prior studies reach conflicting conclusions on the potential relationship between radioactive iodine and both subsequent cancer incidence and mortality. We review recent publications that add to our understanding of this important clinical question.