Based on the efficacy of sirolimus, an mTOR inhibitor, in angiomyolipomas associated with tuberous sclerosis complex (79, 80) and Kaposi sarcoma (81), sirolimus was first used in a child with Kaposiform hemangioendothelioma in 2010 (82). The gene discussed is MTOR; the disease is kaposiform hemangioendothelioma.