Case Report Deep-Seated Kaposiform Hemangioendothelioma Presenting with Recurrent Hemorrhagic Episodes: A Diagnostic Challenge

Introduction: Kaposiform hemangioendothelioma (KHE) is a rare vascular tumor frequently complicated by Kasabach–Merritt phenomenon (KMP). Case Presentation: A 21-month-old boy presented with an initial spontaneous scalp hematoma, recurrent hemorrhagic episodes, and progressive consumptive coagulopathy. Imaging revealed an extensive peri- and paravertebral infiltrative mass involving the thoracic and lumbosacral spine, consistent with KHE. Biopsy was deferred because of high bleeding risk. Treatment with sirolimus led to rapid clinical and hematologic remission. At 3.5 years of follow-up, the patient remains free of recurrent KMP with sustained disease control and mild radiological regression. Conclusion: This case highlights the diagnostic challenges of deep-seated KHE and the pivotal role of imaging when biopsy is unsafe.