LAUSR

OBJECTIVE To determine the outcome of iodine-131 (131I) treatment regimens in thyroidectomy patients with differentiated thyroid cancer. MATERIALS AND METHODS Based on Taiwan's National Health Insurance Research Database (NHIRD) during the period from January 1, 2000 to December 31, 2010, 390 patients with well-differentiated thyroid cancer who underwent 131I treatment after thyroidectomy were enrolled in this study. Patients were classified into six groups according to the type of thyroidectomy and initial activity regimen of 131I treatment. The clinical outcome of 131I treatment was evaluated by total treatment number and medical expenditure, including costs for hospitalization and laboratory tests together with initial and subsequent 131I treatments. Multiple linear regression analysis was applied to analyze the factor(s) significantly affecting the outcome of 131I treatment. RESULTS Increased activity of the initial 131I regimen reduced the total treatment number significantly for unilateral total thyroidectomy with initial 100-150mCi 131I, and mildly for bilateral total thyroidectomy with initial 100-150mCi 131I and radical thyroidectomy with initial 30-99mCi 131I. Increased activity of the initial 131I regimen reduced total medical expenditure significantly for unilateral, and mildly for bilateral total thyroidectomy both with initial 30-99mCi 131I. CONCLUSION For patients with specific thyroidectomy for differentiated thyroid cancer, a high initial regimen of 131I treatment is more effective than the low activity regimen. An increased activity of the initial 131I regimen significantly reduced the total treatment number and medical expenditure.