Efficacy and absorption of topical sirolimus for the treatment of vascular anomalies in children: A case series

Background/ObjectivesEfficacy of topical sirolimus has recently been described in lymphatic anomalies but not in other types of vascular anomalies. To our knowledge, systemic absorption of topical sirolimus in these lesions has not yet been reported. The objective was to evaluate the efficacy, tolerance, and absorption of topical sirolimus 0.1% with different types of vascular anomalies in children. MethodsSirolimus 0.1% was applied on cutaneous vascular anomalies in six children aged 2-17. These anomalies consisted of three extratruncular micro- and macrocystic lymphatic malformations and one each verrucous venous malformation, truncular lymphatic malformation with angiokeratomas, and infantile hemangioma. Sirolimus blood levels were measured after 1week, 1month, and 3months. ResultsA rapid decrease in the size of superficial lymphatic malformations in three of six patients and a significant decrease in discharge from oozing lesions were observed. Response occurred in less than 3months. The truncular lymphatic malformation, verrucous venous malformation, and infantile hemangioma did not respond to topical sirolimus. Sirolimus levels were undetectable. Adverse effects were limited to local irritation. ConclusionsTopical sirolimus 0.1% is a useful treatment for cutaneous manifestations of extratruncular lymphatic malformations. The only adverse effect is local irritation. No systemic effects are expected, because blood levels are clinically insignificant.