Multi-level factors associated with more intensive use of radioactive iodine for low-risk thyroid cancer.

CONTEXT The use of radioactive iodine (RAI) for low-risk thyroid cancer is common, and variation in its use exists, despite the lack of benefit for low-risk disease and potential harms and costs. OBJECTIVE To simultaneously assess patient- and physician-level factors associated with patient-reported receipt of RAI for low-risk thyroid cancer. DESIGN, SETTING, PARTICIPANTS This population-based survey study of patients with newly-diagnosed differentiated thyroid cancer identified via the Surveillance Epidemiology and End Results (SEER) registries of Georgia and Los Angeles County included 989 patients with low-risk thyroid cancer, linked to 345 of their treating general surgeons, otolaryngologists and endocrinologists. MAIN OUTCOMES Patient-reported receipt of RAI for low-risk thyroid cancer. RESULTS Among this sample, 48% of patients reported receiving RAI, and 23% of their physicians reported they would use RAI for low-risk thyroid cancer. Patients were more likely to report receiving RAI if they were treated by a physician who reported they would use RAI for low-risk thyroid cancer compared to those whose physician reported they would not use RAI (Adjusted OR: 1.84, 95%CI: 1.29-2.61). The odds of patients reporting they received RAI was 55% lower among patients whose physicians reported they saw a higher volume of patients with thyroid cancer (40+ vs. 0-20) (Adjusted OR: 0.45, 0.30-0.67). CONCLUSIONS Physician perspectives and attitudes about using RAI, as well as patient volume, influence RAI use for low-risk thyroid cancer. Efforts to reduce overuse of RAI in low-risk thyroid cancer should include interventions targeted towards physicians, in addition to patients.