KAPOSIFORM HEMANGIOENDOTHELIOMA - AN AGGRESSIVE, LOCALLY INVASIVE VASCULAR TUMOR THAT CAN MIMIC HEMANGIOMA OF INFANCY

Background: Kaposiform hemangioendothelioma is a rare, aggressive vasc ular proliferation in children that is clinically and histologically d istinct from hemangioma of infancy. It often manifests later than infa ntile hemangioma, and complication by Kasabach-Merritt syndrome is com mon. Observations: We examined 3 children with kaposiform hemangioendo thelioma, all of whom were initially misdiagnosed as having infantile hemangioma: All 3 children developed Kasabach-Merritt syndrome, in ass ociation with a rapidly growing cutaneous vascular mass. Treatment wit h systemic corticosteroids, interferon alfa, vincristine, and radiatio n therapy appeared to halt progression of the disease. None had eviden ce of human herpesvirus 8 infection. Conclusions: Cutaneous kaposiform hemangioendothelioma may appear in early infancy but often appears mo nths to years later. It is frequently complicated by Kasabach-Merritt syndrome, has no known association with Kaposi sarcoma related to huma n immunodeficiency virus infection, and demonstrates aggressive local behavior with invasion but not distant metastasis. Awareness of this e ntity is important to prevent a mistaken diagnosis of common hemangiom a of infancy.