Different Radioiodine Dose for Remnant Thyroid Ablation in Patients With Differentiated Thyroid Cancer A Meta-analysis

Objective Remnant thyroid ablation is crucial in the management of patients with differentiated thyroid cancer. However, the optimal dose of radioactive I-131 for ablation is still controversial. This study aimed to compare the success rate of different activities of I-131 for postoperative remnant ablation in randomized controlled trials (RCTs) and to determine the optimal dose. Patients and Methods Sources were retrieved from the Cochrane Library, Medline, Embase, Scopus, and Google Scholar until March 2014. All RCTs that assessed the efficacy of different doses of I-131 for ablation were selected. After data extraction, statistics were performed by Review Manager 5.2 software. Results Seventeen RCTs were considered eligible, involving 3737 patients. The overall methodological quality of the studies was good. The rate of successful remnant ablation of low versus moderate I-131 activities (risk ratio [RR], 0.89; 95% confidence interval [CI], 0.80-1.00; P = 0.06) and moderate versus high I-131 activities (RR, 0.94; 95% CI, 0.89-1.00; P = 0.05) showed no significant differences. However, high I-131 activities had 11% higher successful ablation rate than low activities with an RR of 0.89 (95% CI, 0.81-0.97; P = 0.008), which was significant. Conclusions We summarized all available randomized evidence to demonstrate that high dose of I-131 was significantly better than low dose to achieve successful remnant thyroid ablation.