Background Current guidelines recommend radiofrequency ablation (RFA) as the first-line treatment for benign thyroid nodules. Purpose To compare the efficacy and safety of microwave ablation (MWA) and RFA for the treatment of predominantly solid benign thyroid nodules. Materials and Methods This prospective, randomized, open-label, multicenter study was conducted from August 2019 to February 2023. Participants with nonfunctioning, predominantly solid benign thyroid nodules from five institutions were randomly assigned with a 1:1 ratio to receive MWA or RFA treatment. Participants were followed up for at least 2 years. Primary outcomes were 6-month and 2-year volume reduction rate (VRR) of nodules after ablation. Secondary outcomes included VRR change over time, complications, and technique efficacy (defined as volumetric reduction ≥ 50% of the initial nodule volume). Continuous variables and categorical variables were compared using the t test and the χ2 test or Fisher exact test, respectively. Results This study included 76 participants in the MWA group (mean age, 46 years ± 12 [SD]; 58 female participants) and 76 in the RFA group (mean age, 50 years ± 13; 56 female participants). MWA was noninferior to RFA in terms of 6-month (mean difference, -5.6%; P = .01) and 2-year (-2.4%; P < .001) VRR after ablation. Comparing MWA and RFA, no evidence of a difference was observed for VRR change over time (mean difference from mixed-effects analysis, 6.9% [95% CI: -0.5, 13.9]; P = .73) or technique efficacy (91% vs 86%; P = .40). The most common major complication was voice change, which occurred in 6.6% of participants in the MWA group and 1.3% of participants in the RFA group (P = .21). Conclusion MWA and RFA showed comparable efficacy for treating participants with predominantly solid benign thyroid nodules. However, a larger sample size is needed to demonstrate that safety is comparable between the procedures. ClinicalTrials.gov Identifier: NCT04046354 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by McGahan in this issue.

中文翻译：

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微波与射频消融治疗主要实性良性甲状腺结节：一项随机对照试验。


背景 目前的指南建议将射频消融术 （RFA） 作为良性甲状腺结节的一线治疗。目的 比较微波消融术 （MWA） 和 RFA 治疗以实性为主的良性甲状腺结节的有效性和安全性。材料和方法 这项前瞻性、随机、开放标签、多中心研究于 2019 年 8 月至 2023 年 2 月进行。来自 5 个机构的无功能、主要是实性良性甲状腺结节的参与者以 1：1 的比例随机分配接受 MWA 或 RFA 治疗。参与者接受了至少 2 年的随访。主要结局是消融后结节的 6 个月和 2 年体积减少率 （VRR）。次要结局包括 VRR 随时间的变化、并发症和技术疗效 （定义为体积减少≥初始结节体积的 50%）。分别使用 t 检验和 χ2 检验或 Fisher 精确检验比较连续变量和分类变量。结果 本研究包括 MWA 组 76 名参与者 （平均年龄 46 岁 ± 12 [SD];58 名女性参与者） 和 RFA 组 76 名参与者 （平均年龄 50 岁 ± 13 岁;56 名女性参与者）。MWA 在 6 个月方面不劣于 RFA（平均差，-5.6%;P = .01） 和 2 年 （-2.4%;P < .001） 消融后的 VRR。比较 MWA 和 RFA，没有证据表明 VRR 随时间的变化存在差异（来自混合效应分析的平均差异，6.9% [95% CI： -0.5， 13.9];P = .73） 或技术有效性 （91% 对 86%;P = .40）。最常见的主要并发症是声音改变，MWA 组有 6.6% 的参与者发生，RFA 组有 1.3% 的参与者发生 （P = .21）。 结论 MWA 和 RFA 在治疗以实性良性甲状腺结节为主的参与者方面显示出相当的疗效。然而，需要更大的样本量来证明这些程序之间的安全性是可比的。ClinicalTrials.gov 标识符：NCT04046354 © RSNA， 2024 本文提供补充材料。另请参见 McGahan 在本期的社论。