Radioiodine or Surgery for Toxic Thyroid Adenoma: Dissecting an Important Decision. A Cost-Effectiveness Analysis

Objective: To examine the cost effectiveness of therapeutic strategies for toxic thyroid adenoma. Design: Markov state transition decision analytic model. Setting: Ambulatory and inpatient. Patients: Hypothetical cohort of 40- year-old women with toxic thyroid adenomas. Patient age was varied in sensitivity analyses. Data on the prevalence of coincident thyroid cancer, complications, and treatment efficacies were derived from a systematic review of the literature. Interventions: Thyroid lobectomy after a 3 month-course of antithyroid drugs (ATDs), high-dose (555 MBq) RAI, and lifelong ATDs. Measurements and main results: Outcomes were measured in quality-adjusted life years (QALYs). Costs were estimated from the health care system perspective. Future costs and effectiveness were discounted at 3% per year. For a 40- year-old woman, surgery was the most effective, while low-dose RAI was the least costly. The marginal costeffectiveness of surgery versus low-dose RAI was $13,183 per QALY. Surgery was less costly and more effective than lifelong ATDs. RAI was more effective than surgery if surgical mortality exceeded 0.90% (base-case 0.001%). Surgery provided relatively inexpensive gains (