Summary:
Epitheliolid hemanigoendothelioma of the liver is a very rare vascular tumor. We report the case
of this tumor found during the autopsy of a 74-year-old man. The liver was infiltrated by multiple
greyish nodes (diam. 3-30 mm), partially calcified. Microscopically, the tumor was composed of
dense sclerotic and fibrous stroma with focal calcifications. In this stroma, groups and cords of
irregular cells of two main types were dispersed. The first type was represented by big cells with
large clear eosinophilic cytoplasm. The second cell type was characterised by medium-sized elongated, sometimes bizarre-shaped cells. Tumorous cells did not produce mucin. Immunohistochemically, the tumorous cells were positive for FVIIIR - Ag, actin, vimentin, and desmin and also
showed disperse weak positivity for S100 protein. Staining for epithelial membrane antigene
(EMA), keratins, and CD68 was negative. Neoplastic cells were positive for Ulex europaeus lectin.
Electronmicroscopically, the tumorous cells had irregular nuclei, lobular or cleft shape with one
or two nucleoli. Cytoplasm contained a high amount of intermediate filaments forming large
aggregates. The cells were connected by desmosomes and partially surrounded by dense basal
lamina. The diagnosis of epithelioid hemangioendothelioma is based on a histological picture,
supported by immunohistochemical positivity for FVIIIR: Ag and Ulex europaeus and by additional ultrastructural study.
Key words:
Key words: epithelioid hemangioendothelioma - liver - electron microscopy - immunohistochemis-
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