Kaposiform hemangioendothelioma is a rare and agressive vascular tumor that affects children. It may have potentially fatal consequences. The tumor can act as a trap for platelets: the child may have as a consequence a very small number of platelets (less than 40,000 mm3). Treatments are complicated. There are several drugs (including corticosteroids, Interferon 2a, or chemotherapy) and certain forms of ratiotherapy that may be considered, and have shown variable degrees of success.