Short-Term Efficacy and Safety of Topical Sirolimus Gel in Pediatric Superficial Microcystic Lymphatic Malformations: A Single-Center Interventional Study of 30 Patients.

OBJECTIVE

To evaluate the efficacy and safety of 0.2% topical sirolimus gel for pediatric superficial microcystic lymphatic malformations (LMs).

METHODS

This single-center interventional study included 30 pediatric patients (14 males and 16 females; aged 2-15 years) with superficial microcystic lymphatic malformations. All patients received 0.2% topical sirolimus gel twice daily for 12 weeks according to a predefined treatment and follow-up protocol. Clinical efficacy was assessed at baseline and week 12 using clinical examination, standardized photography, symptom scores, and available imaging findings, together with a four-grade physician-assessed response scale. Adverse events were monitored throughout treatment, and blood sirolimus concentrations were measured at weeks 4 and 12.

RESULTS

All patients showed lesion reduction, with an overall response rate of 96% (29/30). At week 12, efficacy was graded as IV in 10 patients, III in 11, II in 8, and I in 1. Among patients with pain symptoms, pain scores decreased significantly after treatment (2.88 ± 0.78 vs 1.18 ± 0.88; P < 0.05). In 10 patients with measurable lesions, maximum lesion diameter decreased significantly from 3.22 ± 1.36 cm to 1.89 ± 1.33 cm (P < 0.05). Only mild local adverse effects were observed, and blood sirolimus concentrations remained below 2.0 ng/mL in all patients.

CONCLUSION

Topical sirolimus gel demonstrated favorable efficacy and safety for pediatric superficial microcystic LMs.