Clinical observation of ultrasound-guided microwave ablation for 1717 benign breast lesions: a multicenter study.

OBJECTIVES: To evaluate the clinical effectiveness of ultrasound-guided microwave ablation (MWA) for benign breast lesions (BBLs). MATERIALS AND METHODS: This prospective multicenter study (January 2020 to July 2023) included 1043 patients from seven centers with 1717 biopsy-proven benign breast lesions. The study analyzed contrast-enhanced ultrasound (CEUS)-confirmed ablation outcomes, complications, volume reduction ratio (VRR), cosmetic satisfaction, and time of complete absorption (TCA). RESULTS: On postoperative day 1, CEUS demonstrated complete non-enhancement in 1713/1717 lesions (99.77%) after the initial ablation; four lesions with residual enhancement underwent immediate supplementary ablation with subsequent CEUS-confirmed non-enhancement. The mean maximum lesion diameter was 1.38 ± 0.25 cm. After a median follow-up of 38.7 months, 1643 out of 1717 lesions (95.69%) were not palpable. The 12-month VRR was 99.98% for lesions ≤ 1.0 cm, 98.20% for lesions 1.0 to 2.0 cm, and 85.43% for lesions ≥ 2.0 cm. VRR was significantly associated with lesion size and procedural parameters, including ablation power and the number of antenna insertions (all p < 0.001). Postoperative pain was mild (VAS 0.52 ± 0.43), and no patients discontinued treatment due to pain. Minor complications included fat liquefaction in 3 of 1717 lesions (0.17%) and self-limiting nodularity or fibrosis in 106 lesions (6.2%). No major complications, such as burns, infection, or bleeding, occurred. Cosmetic satisfaction was rated as excellent in 92.4% of patients and good in 7.6%. CONCLUSION: Percutaneous MWA is a safe, effective, and minimally invasive treatment for BBLs, providing durable lesion regression and excellent cosmetic outcomes with minimal self-limiting complications. CRITICAL RELEVANCE STATEMENT: This multicenter study supports ultrasound-guided microwave ablation as a feasible minimally invasive treatment for benign breast lesions, providing durable long-term regression and favorable cosmetic outcomes while helping reduce procedure-related tissue trauma associated with surgery. KEY POINTS: Long-term multicenter evidence for ultrasound-guided microwave ablation of benign breast lesions remains limited, particularly regarding safety, lesion regression, and cosmetic outcomes. Microwave ablation achieved 99.77% day-1 contrast-enhanced ultrasound (CEUS) non-enhancement, durable lesion regression, minimal complications, and high cosmetic satisfaction during long-term follow-up.