Primary epithelioid hemangioendothelioma of the brain.

Epithelioid hemangioendothelioma is an uncommon form of endothelial neoplasm, one of intermediate-grade malignancy and relatively favorable prognosis. Herein we report the third and fourth cases described in the central nervous system and compare their clinical and pathologic properties with those arising at systemic sites. Both patients presented with signs and symptoms of a mass lesion with seizures present in both cases. Imaging studies revealed well-demarcated mass lesions with surrounding edema. Gross total removal was accomplished surgically in both cases One case was partially cystic and nodular; the other was firm, focally gritty, and cartilaginous in appearance. Histologically they were identical to hemangioendotheliomas of other locales: multinodular neoplasms with regional variation in cellularity, cords and clusters of epithelioid cells with variable attempts at lumen formation, and spindled cells associated with a fibromyxoid matrix. Immunohistochemical stains confirmed the endothelial natures of the cells. These cases and those previously reported were treated with surgical excision. The few patients described have ranged in age from infants to older adults. Some patients have had residual neurologic defects, but no deaths due to tumor have been reported.