Analysis of the Efficacy and Safety of Ultrasound-guided Pingyangmycin Combined with Microwave Ablation in the Treatment of Microcystic Lymphatic Malformations in Children

Objective: To evaluate the efficacy and safety of ultrasound-guided Pingyangmycin sclerotherapy combined with microwave ablation (MWA) for treating microcystic lymphatic malformations (LMs) in children, compared to Pingyangmycin sclerotherapy alone. Methods: This single-group study enrolled 108 pediatric patients with microcystic LM hospitalized between January 2022 and September 2023. Patients were divided into two groups based on treatment received: the Sclerotherapy group (n = 74, Pingyangmycin injection alone) and the Combination group (n = 34, Pingyangmycin injection followed by MWA). Baseline characteristics, lesion parameters (location, initial volume, intralesional fluid characteristics), treatment details (Pingyangmycin dosage, number of sessions), efficacy outcomes (Volume Reduction Rate [VRR], Efficacy Grade), and complications were recorded and statistically compared. Results: The Combination group had significantly larger initial lesion volumes (59.2 mL vs. 11.6 mL, p < 0.001) and were predominantly located in the lower limbs (76.5% vs. 29.7%), while the Sclerotherapy group lesions were mainly in the face & neck (33.8% vs. 2.9%). The Combination group used significantly less Pingyangmycin (median 0.5 mg vs. 2.0 mg, p < 0.001, a 75% reduction) and required fewer treatment sessions (88.2% vs. 47.3% completed in one session, p < 0.001). VRR was comparable between groups (Combination: 57.4% vs. Sclerotherapy: 52.0%, p = 0.344), as was the proportion achieving >75% reduction (Grade IV: 26.5% vs. 24.3%, p = 0.887). Overall complication rates were similar (p = 0.232), though mild pain incidence was higher in the Combination group (41.2% vs. 21.6%). Conclusion: Ultrasound-guided combined Pingyangmycin and MWA therapy significantly reduces Pingyangmycin dosage and treatment frequency while achieving comparable efficacy to sclerotherapy alone in pediatric microcystic LM. The dual chemical-thermal ablation mechanism offers a precise, minimally invasive option, particularly advantageous for craniofacial lesions. Larger, long-term studies are warranted to validate these findings.