Efficacy and safety of targeted therapy for radioiodine-refractory differentiated thyroid cancer: a meta-analysis.

PURPOSE To evaluate the efficacy and safety of current targeted drug therapies for radioiodine-refractory differentiated thyroid cancer (RR-DTC). METHODS This was a meta-analysis of relevant randomized controlled trials (RCTs) and single-arm studies searched across PubMed, Embase, Cochranes, and Web of Sciences up to September 12, 2023. Stata15.0 software was used to assess overall survival (OS), progression-free survival (PFS), disease control rate (DCR), objective response rate (ORR), and adverse effects (AEs). The Cochrane Bias Risk tool was used to assess literature quality and trial bias and RevMan 5.4 was used to generate a quality assessment map. RESULTS A total of 8 RCTs and 17 single-arm studies with 3,270 patients on 7 drugs-vandetanib, sorafenib, lenvatinib, cabozantinib, apatinib, donafenib, and anlotinib-were included. Targeted therapy with these drugs effectively prolonged PFS and OS in patients with RR-DTC with overall HRs of 0.35 (95% CI 0.23-0.53, P < 0.00001) and 0.53 (95% CI 0.32-0.86, P < 0.00001), respectively. ORR and DCR were also prolonged, with overall RRs of 27.63 (95% CI 12.39-61.61, P<0.00001) and 1.66 (95% CI 1.48-1.86, P<0.00001), respectively. The subgroup analysis using Effect Size (ES) showed that apatinib had the best effect on ORR with an ES of 0.66 (95% CI 0.49-0.83, P<0.00001) and DCR with a ES of 0.95 (95% CI 0.91-1.00, P<0.00001). Common drug adverse effects included hypertension, diarrhea, proteinuria, and fatigue. CONCLUSION The currently used targeted drug therapies for RR-DTC can significantly improve clinical outcomes and the new drug apatinib demonstrates promise for potentially superior performance.