Retroperitoneal kaposiform hemangioendothelioma complicated by Kasabach-Merritt phenomenon and obstructive jaundice: A retrospective series of 3 patients treated with sirolimus.

We present a retrospective case series of 3 patients with retroperitoneal kaposiform hemangioendothelioma (KHE) complicated by Kasabach-Merritt phenomenon (KMP) and biliary obstruction. We found sirolimus to be a safe and effective treatment for these patients who were refractory to other treatment modalities. However, our patients were slow to respond in comparison to published reports of sirolimus use for KHE without biliary obstruction. We postulate that therapeutic serum levels of sirolimus may be affected by biliary obstruction and improved with surgical alleviation of the obstruction.