微波消融（MWA）在治疗单源性乳头状甲状腺微小癌（UPTMC）方面取得了出色的长期疗效。目前对多源性乳头状甲状腺微小癌（MPTMC）的治疗效果尚未明确。因此，我们评估了MWA治疗低风险MPTMC的长期疗效，并为临床指南的修订提供了循证医学依据。 本研究包括66例MPTMC患者，共计158个病灶，全部接受MWA治疗。我们收集并回顾性分析了患者在MWA前、治疗后1、3、6、12个月及随后每6个月的随访数据，直至治疗后5年。我们评估了随访期间MWA的并发症率、技术成功率（TSR）、病灶体积缩小率（VRR）以及完全消失率（CDR），以及在肿瘤进展和延迟手术的患者中。 随访60个月后，66例患者的158个病灶全部消失，体积从43.82 mm3减少至0.00 mm3。TSR和VRR均为100%。1年、2年和3年的CDR分别为57.59%、93.67%和100%。并发症率为3.03%（2/66），肿瘤进展率为3.03%（2/66），包括一例新的甲状腺内病灶和一例颈部淋巴结转移（LNM）。这些病灶经过MWA治疗后，消失于随访期间。 超声引导下的MWA治疗低风险MPTMC安全有效，可作为拒绝手术或主动观察（AS）的患者的替代选择。 本研究得出结论，超声引导下的微波消融治疗低风险多源性乳头状甲状腺微小癌是安全有效的，可作为拒绝手术或主动观察的患者的替代选择。• 超声引导下的微波消融治疗低风险多源性乳头状甲状腺微小癌是安全有效的。• 在5年的随访中，经过微波消融治疗的多源性乳头状甲状腺微小癌患者具有良好预后。• 为临床指南的修订提供循证医学依据。 © 2023. 作者授予欧洲放射学会独家许可。

Microwave ablation (MWA) has achieved excellent long-term efficacy in treating unifocal papillary thyroid microcarcinoma (UPTMC). The therapeutic effect of this treatment on multifocal papillary thyroid microcarcinoma (MPTMC) is unknown. Therefore, we evaluated the long-term efficacy of MWA for low-risk MPTMC and to provide evidence-based medicine for the revision of clinical guidelines.This study included 66 MPTMC patients with a total of 158 lesions, all of whom received MWA. We collected and retrospectively analyzed the patients' follow-up data before MWA, at 1, 3, 6, and 12 months posttreatment and every 6 months thereafter until 5 years posttreatment. We evaluated the MWA complication rate, technical success rate (TSR), lesion volume reduction rate (VRR), and complete disappearance rate (CDR) during follow-up and in those patients with tumor progression and delayed surgery.After 60 months of follow-up, all 158 lesions disappeared in 66 patients, and the volume was reduced from 43.82 mm3 to 0.00 mm3. The TSR and VRR were both 100%. The CDRs at 1 year, 2 years, and 3 years were 57.59%, 93.67%, and 100%, respectively. The complication rate was 3.03% (2/66), and the incidence of tumor progression was 3.03% (2/66), including one new intrathyroidal lesion and one cervical lymph node metastasis (LNM). These lesions were retreated with MWA, and the lesions disappeared during the follow-up period.Ultrasound-guided MWA for low-risk MPTMC is safe and effective and may serve as an alternative option for patients who refuse surgery or active surveillance (AS).This study concludes that ultrasound-guided microwave ablation for low-risk multifocal papillary thyroid microcarcinoma is safe and effective and may serve as an alternative option for patients who refuse surgery or active surveillance.• Ultrasound-guided microwave ablation for low-risk multifocal papillary thyroid microcarcinoma is safe and effective. • During 5 years of follow-up, multifocal papillary thyroid microcarcinoma patients treated with microwave ablation had a favorable prognosis. • To provide evidence-based medicine for the revision of clinical guidelines.© 2023. The Author(s), under exclusive licence to European Society of Radiology.