SAT-338 - Efficacy and Safety of Microwave Ablation for Primary Hyperthyroidism: A Single-Arm Meta-Analysis

Introduction: Primary hyperthyroidism is a prevalent endocrine disorder associated with significant clinical burden. Established treatments, including surgery, radioactive iodine, and antithyroid drugs, carry limitations related to efficacy, recurrence, and complications. Microwave ablation (MWA) has recently emerged as a minimally invasive alternative with potential to improve outcomes. This review and meta-analysis aimed to synthesize available evidence on the efficacy and safety of MWA in primary hyperthyroidism.
Methodology: This systematic review and meta-analysis was conducted in line with Cochrane and PRISMA 2020 recommendations. We searched PubMed, Embase, Scopus, Cochrane Library, ClinicalTrials.gov, Chongqing VIP Chinese Journals Platform, Google Scholar and Xueshu Baidu from inception to August 26, 2025 for single-arm studies evaluating the effectiveness of MWA in treating patients with primary hyperthyroidism. Statistical analyses were performed in R/RStudio (v2025.05.1+513) with random-effects model. Dichotomous outcomes were pooled as proportions, stabilized with Freeman-Tukey double-arcsine (PFT) transformations, and continuous outcomes were pooled as weighted means. Risk of bias was appraised using the Methodological Index for Non-Randomized Studies (MINORS) tool. Ethical approval was not needed to conduct this study as only published data were used.

Results: Nine studies were included. Eight studies were conducted in China, and one in Russia. The total procedural duration in the studies ranged from 43 to 55.6 minutes. Pooled analysis estimated the technical success rate to be 99% (95% CI [90% to 100%]), and recurrence rates were minimal (2%, 95% CI [0% to 6%]). Complete remission rates were high (86%, 95% CI [70% to 97%]). Procedure-related overall complication rates were low (7%, 95% CI [3% to 13%]). Most participants had reductions in thyroid size and heart rate, with stabilization of thyroid function tests (TFTs) towards physiologic values. Study quality was assessed to be moderate for all studies.

Conclusion: This single-arm meta-analysis suggests that microwave ablation may be a safe and effective minimally invasive option for selected patients with primary hyperthyroidism, achieving high remission and low recurrence rates with acceptable complication profiles. However, the current evidence is limited by moderate-quality, single-arm studies, regionally clustered to Asian countries. Well-designed, multicentric comparative trials against established therapies are needed before MWA can be recommended for a routine usage in broader clinical practices.

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