Association of Radioactive Iodine Treatment With Cancer Mortality in Patients With Hyperthyroidism

Abstract

In the United States, the prevalence of hyperthyroidism is 1.2% (0.5% overt and 0.7% subclinical), and most cases are due to Graves disease.¹ Radioactive iodine (RAI; sodium iodide I 131, or Na¹³¹I) has been extensively used to treat hyperthyroidism since the 1940s and has been the preferred first-line treatment by US physicians for uncomplicated Graves disease.^2,3 However, in recent decades, preference for RAI therapy as a primary treatment for Graves disease has declined in favor of antithyroid drugs, likely reflecting the increased awareness of an association between RAI and worsening of Graves ophthalmopathy as well as concerns about risks of radiation-induced cancer, whereas preference for initial surgical treatment has remained low.^3,4