Refractory Kaposiform Hemangioendothelioma Associated with the Chromosomal Translocation t(13;16)(q14;p13.3).

We report a 7-year-old male with a history of recurrent kaposiform hemangioendothelioma (KHE) in the sacral area and multiple thoracic vertebral lesions. Tumor karyotyping revealed the balanced translocation t(13;16)(q14;p13.3). He had mildly decreased platelet counts but never experienced any episodes of Kasabach-Merritt phenomenon. He was treated with vincristine for 1 year but improvement was minor. Significant clinical improvement was seen with sirolimus therapy. To the best of our knowledge, this is the first report to demonstrate that KHE is associated with a clonal karyotypic abnormality.