Primary epithelioid hemangioendothelioma in the clival region: a case report and literature review.

Epithelioid hemangioendothelioma (EHE) is a rare and low-grade vascular tumor, which usually occurs in the soft tissue, liver, breast, lung and skeleton. Here we submit a case with EHE of the clival region. A 58-year-old woman was admitted with a medical history of 3 months headache and 1 month visual deterioration. MRI revealed a well-circumscribed mass of 4.0 cm × 3.0 cm with bony invasion. The tumor was subtotally removed in a piecemeal fashion. Histologically, the tumor was composed of epithelioid cells with eosinophilic cytoplasm and intracytoplasmic vacuoles. Immunohistochemically, the tumor cells were positive for the markers CD31, CD34, factor VIII and vimentin. The pathological result was interpretated as EHE of the clival region. EHE is an uncommon vascular tumor, which is rarely seen in the clival region. Definitive diagnosis depends on histopathologic and immunohistochemical features.