Guided Discontinuation Versus Maintenance Treatment of Sirolimus in Pediatric Patients With Kaposiform Hemangioendothelioma

Kaposiform Hemangioendothelioma (KHE) is a rare vascular tumor that occurs in infants and children. KHE is characterized by sheets of spindle cells with an infiltrative pattern in the dermis, subcutaneous fat, and muscle. It is locally aggressive and can cause Kasabach-Merritt phenomenon, a serious life-threatening coagulopathy characterized by profound thrombocytopenia and hypofibrinogenemia. Sirolimus, one of the mTOR inhibitors, has become a new and very effective treatment, which is especially reliable for KHE with KMP and has acceptable side effects. However, there is yet no strong evidence on the best practice of treatment length of sirolimus. This randomized controlled trial aims to compare guided discontinuation with maintenance treatment in pediatric patients with KHE in order to provide a basis for the optimal treatment duration of sirolimus, as well as the clinical characteristics of pediatric patients who can safely reduce the dose till withdrawal.