Epithelioid hemangioendothelioma of liver is a very rare tumor of vascular origin, the most peculiar feature of which is that it is composed of endothelial cells closely resembling epithelial cells. We present a primary epithelioid hemangioendothelioma of liver in a 40-year-old male. This tumor was composed of an ill-defined yellowish white, 7 x 4cm sized, firm, solid mass and small satellite nodules in the right lobe of liver. Microscopically, two types of tumor cells-dendritic and epithelioid-were identified. The neoplastic cells infiltrated into sinusoids and intrahepatic veins. The background of tumor showed marked sclerotic change and focal proliferation of bile ductules. Confirmation of the endothelial origin of these cells was provided by positive immunoperoxidase staining for factor VIII-related antigen, and by electron mi-croscopic demonstration of Weibel-Palade body. This is the first case of epithelioid heman- gioendothelioma of liver documented in Korea. We report this case in view of its scarcity and distinctive morphologic features that allow differentiation from sclerosing carcinoma and angiosarcoma.
Epithelioid hemangioendothelioma is a rare vascular tumor of borderline malignancy which is characterized by the presence of "epithelioid" or "histiocytoid" endothelial cells.
Superficial and deep tumors have been recognized in the extremities, head, neck, chest, and mediastinum of adult patients. It may also occur as a primary tumor of liver, bone, and other visceral organs. Few effusion cytologic findings of epithelioid hemangioendothelioma have been reported. We report a case of composite epithelioid hemangioendothelioma with focal epithelioid angiosarcomatous areas of the iliac bone and adjacent soft tissue in a 38-year-old female, which, during its metastatic course, was presented as a pleural effusion. The effusion was cellular with epithelioid cells presenting both singly and in clusters. The tumor cells were round to ovoid showing cytoplasmic vacuolization, variability in cell size, and prominent nucleoli. The effusion smears and cell block sections revealed strong positive staining for CD31 and vimentin, weak positive for CD34 and Factor VIII-related antigen, and negative for cytokeratin, CEA, and calretinin.
The cytologic findings in this case were similar to that of metastatic adenocarcinoma or malignant mesothelioma.
Therefore, immunocytochemical staining in smear and cell block is a helpful tool to differentiate malignant "epithelioid" cells in effusion.
Epithelioid hemangioendothelioma is a recently described vascular neoplasm characterized by epitheloiod endothelial linings and its borderline biologic behavior. We report a case of epithelioid hemangioendothelioma in a 6-year-old male. The tumor was presented as a non-tender dermal nodule on the left middle finger. The microscopic sections revealed irregular proliferation of vascular channels lined by epithelioid cells with histiocytoid features and frequent intracytoplasmic vacuoles, mimicking so called signet ring cells. Immunohistochemical stainings for factor VIII and vimentin were positive both in epithelioid and vacuolated endothelial cell. Electron microscopic finding reveals abundant intermediate filaments.
Intravascular bronchioloaveolar tumor is now recognized as a pulmonary form of epithelioid hemangioendothelioma, being manifested with bilateral multiple pulmonary nodules in young women. This 34-year-old woman received two occasions of open lung biopsies with interval of 1 year for diffuse nodular infiltrations in both lung fields. Repeated radiographic study 3 year later showed no significant progression of the pulmonary nodular lesions except for pleural effusion. Two occasions of open lung biopsies disclosed similar multiple discrete nodules which consisted of central acellular areas with lacuna-like ghosts and peripheral cellular zone. The tumor cells grew in micropolypoid fashion with preservation of background alveolar frame-works. Ultrastructure disclosed most of neoplastic cells presenting with the features suggestive of endothelial differentiation, and immunohistochemical study revealed the presence of cellular areas which gave positive reaction to factor VIII-related antigen. We support that this is an additional case of epithelioid hemangioendothelioma of the lung that is manifested with a multicetric intrapulmonary vascular endothelial cell growth featuring a vasoformative tendency and participation of topography-specific histologic modification.