Hepatic epithelioid hemangioendothelioma is a rare tumor of vascular origin, first defined as a specific entity by Weiss and Enzinger [1] in 1982. Clinical manifestation is variable, usually with nonspecific symptoms such as right upper quadrant pain and weight loss. Some patients present with Budd-Chiari syndrome or liver failure; others present with incidental findings [2, 3]. Diagnosis may be difficult. Many published cases are initially misdiagnosed [1, 3].
Although tumor growth may be progressive and lead to hepatic failure, extrahepatic me-tastases, and death, the prognosis is considered more favorable than that of other hepatic malignancies. Hepatic epithelioid hemangioendothelioma is usually denned as a low- to intermediate-grade malignancy [2,3]. Histolog-ically, the tumors are composed of dendritic and epithelioid cells. Tumor cells with intracytoplasmic lumina, occasionally containing RBC, appear as signet ring-like structures (Fig. 1). The stroma is fibrous with myxohyaline areas. Im-munohistochemically, tumors are positive for at least one endothelial marker (factor VLI-related antigen, CD34 or CD31, or both) [2,3] and negative for epithelial markers (cytokeratin and carcinoembryonic antigen). It is important to distinguish this entity from adenocarcinoma and angiosarcoma, because long-term survival is possible. Treatment modalities include hepatic resection; orthotopic liver transplantation, even in cases with known metastases; radiotherapy; chemotherapy with Adriamycin ([doxoru-bicin hydrochloride] Pharmacia and Upjohn, Peapack, NJ); and interferon alpha-2 [2,3].