Epithelioid hemangioendothelioma of bone.

Epithelioid hemangioendothelioma of bone is a rare tumor of vascular origin. A series of 40 cases from the Mayo Clinic files was studied to define the pathologic features of this disease and to evaluate any histologic or clinical factor influencing outcome. More than 50% of the tumors were multicentric, with a predilection for bones of a particular anatomical area. In this series, patients with multifocal tumors did not have a better prognosis than those with unicentric disease. We could not predict the outcome of cases on the basis of the histologic features. Visceral involvement was the most important criterion in predicting prognosis. Resection is still the primary treatment for these tumors. Radiotherapy may be useful for surgically inaccessible tumors. Too few patients have received adjuvant chemotherapy to evaluate its usefulness in this setting.