Sirolimus, a promising treatment for refractory Kaposiform hemangioendothelioma

Background Kaposiform hemangioendothelioma (KHE) is a locally aggressive vascular tumor that usually occurs in infants. It is commonly associated with Kasabach-Merritt phenomenon which is directly responsible for the significant morbidity and mortality, including hemodynamic instability, local invasion, and compression of vital structures. Treatment is particularly difficult for those who had no response to conventional therapies. This paper wants to share experience of mTOR inhibitors sirolimus in the treatment of refractory KHE. Materials and methods Six cases of refractory KHE were diagnosed and treated in Children's Hospital of Fudan University from Jan 2010-June 2013; all of them were treated with sirolimus in June 2012 after failing multiple other therapies. Results In six patients, gender was equally distributed between male and female patients. The mean age at the time of initial diagnosed as KHE was 3.1 +/- 1.8 months. All of them had been pretreated with at least 2 medical therapies. All of them showed significant improvement in clinical status with tolerable side effects. The average time to response was 5.3 +/- 1.0 days; the average stabilization time of platelet was 15.1 +/- 8.0 days; and the average time for sirolimus treated as single agent was 1.7 +/- 0.4 months. No recurrence of their symptoms happened. Conclusions Sirolimus appears to be effective and safe in patients with life-threatening KHE and represents a promising tool in treating refractory KHE.