Epithelioid haemangioendothelioma of the bone tissue.

An epithelioid haemangioendothelioma arising in a 43-year-old Japanese woman is presented. The patient first complained of severe back pain and neurogenic disturbances due to compression fracture of the spinal bone. Radiographically the tumour masses showed osteolytic lesions without reactive new bone formation. Similar lesions were noted in other bones. Biopsy and surgical specimens showed the features of epithelioid haemangioendothelioma. A lymphocyte associated antigen, HLA-DR which has been regarded as a B lymphocyte marker was detected in the tumour cells. The importance of this finding was emphasized with respect to the identification or classification of vascular tumours.