BACKGROUND: The treatment of aggressive fibromatosis (AF) poses a challenge for physicians due to propensity for local recurrence and aggressive nature, with traditional surgical excision often resulting in recurrence. Ultrasound-guided ablation, offering minimal trauma and reusability, has emerged as a novel therapeutic option for invasive fibromas. We report our experience of microwave ablation (MWA) as a local and analgesic treatment for inoperable or recurring AF. METHODS: This study includes 8 patients who underwent percutaneous MWA of 10 AF between November 2021 and November 2023. All patients underwent pain assessment using a visual analog scale (VAS) and preoperative imaging. Patients received clinical and radiological follow-up at 6 months post-procedure, with pain-rating and adverse events being recorded. A long-term follow-up was achieved until 1 November 2024. RESULTS: In this study, the 10 tumors in 8 patients have a preoperative size ranging from 1.84 to 477.96 ml, with a mean of 71.90 ± 147.55 ml. Postoperatively, at 6 months, the lesion sizes ranged from 0 to 174.99 ml, with a mean of 24.97 ± 53.78 ml (P <
0.05). The mean volume reduction ratio (VRR) was 55.86% (range 15.48-100%), with an overall treatment effectiveness rate of 80% (8 out of 10). Long-term follow-up revealed 2 cases meeting complete response (CR) criteria, 4 cases achieving partial response (PR), and 2 cases meeting stable disease (SD) criteria. The average pre-treatment VAS score among the 8 patients was 6.38 (range 5-9), which decreased to 3.0 (range 0-6) after 1 month of treatment, demonstrating a significant average pain reduction of 3.38 (p <
0.05). The study reported an adverse reaction incidence of 12.5% (1/8) due to neural heat damage from ablation, with symptom improvement following supportive care. CONCLUSION: MWA is an effective therapeutic option for the local treatment and for the analgesic management of AF.