LAUSR

Key Points Question Is radioactive iodine (RAI) therapy for hyperthyroidism associated with an increased cancer risk? Findings This systematic review and meta-analysis, including 12 observational studies and 479 452 participants, found that RAI therapy was not associated with a significant increase in overall cancer risk or site-specific cancer incidence or mortality, except for thyroid cancer. However, a linear radiation dose-response association between RAI therapy and solid cancer mortality was observed, based on 2 studies with information on RAI administered dose. Meaning Considering the global use of RAI therapy for hyperthyroidism, further studies are needed to provide quantitative estimates of site-specific cancer risks associated with RAI therapy, particularly at higher doses.