Comparing the therapeutic efficacy of radiofrequency vs. Microwave ablation for non-functioning benign thyroid nodules

Purpose: The aim of the study was to compare the efficacy, procedural features, and safety profile of radiofrequency ablation (RFA) versus microwave ablation (MWA) for the treatment of non-functioning benign thyroid nodules (BTNs). Methods: This retrospective, single-centre, cohort study included 203 nodules treated with RFA and 71 with MWA by a single experienced operator. Multivariate linear regression analysis was performed to identify independent predictors of treatment response, defined as 12-month volume reduction rate (VRR). Complication rates were also compared between RFA and MWA. A 1:1 case-control matching was performed based on baseline nodule volume and composition, yielding two matched cohorts of 66 patients each. VRRs after 6 and 12 months were compared between two groups. Results: In the overall population, similar VRRs were observed after 6 and 12 months. Significant differences in baseline nodule volume (24.35 ± 17.15 ml vs. 17.25 ± 15.22ml; p = 0.001) and in procedure times (519.96 ± 289.45s vs. 649.61 ± 321.05s; p = 0.003) were found for MWA and RFA, respectively. Multivariate analysis identified baseline volume (p < 0.001) and composition (p < 0.033) as significant and independent predictors of VRR. Both techniques showed comparable safety. In the matched cohorts, VRRs after 6-months were similar, while a higher VRR after 12-months was observed for MWA compared to RFA (64.70 ± 13.89% vs. 58.71 ± 16.81%; p = 0.028). Conclusion: RFA and MWA are both safe and effective for treating BTNs. In the overall population, VRRs were similar between RFA and MWA, with MWA requiring shorter procedure times. After matching for key predictors of therapeutic response, MWA demonstrated superior efficacy at 12-months.