Diuretic-enhanced I-131 clearance after ablation therapy for differentiated thyroid cancer.

The authors assessed whether the whole-body radiation burden can be reduced with diuretic enhancement of iodine-131 excretion in patients with thyroid cancer and slow clearance. Whole-body imaging and quantitative I-131 clearance data obtained before and after ablation therapy were evaluated in 56 patients. Fourteen patients with slow pre-ablation therapy clearance (> 50% retention at 24 hours) received oral diuretics after I-131 therapy. Nine patients began taking furosemide 24 hours after I-131 treatment. Five patients had been receiving thiazide diuretics and were continued on the same dose after treatment. The mean half-time of I-131 clearance for the patients treated with furosemide decreased by 12 hours (P < .05) but was not significantly decreased for those who received thiazides or for the patients who did not receive diuretics. Administration of diuretics can improve I-131 clearance in patients with thyroid cancer and slow clearance, reducing the radiation burden and shortening the hospital stay.