We describe a malignant epithelioid hemangioendothelioma arising in the back of a 45-year-old man with pulmonary and bone marrow metastases. Light microscopic and immunohistochemical features of this tumor are presented. Karyotyping revealed several clonal abnormalities: a complex unbalanced translocation [7;22] involving multiple breakpoints (confirmed by fluorescence in situ hybridization), a Robertsonian t(14;14), and loss of the Y chromosome. Monosomy for chromosome 11 was noted in a subset of the tumor cells. To our knowledge a karyotype has not been previously reported for this unusual vascular tumor.