Epithelioid hemangioma is belong to a group of unusual vascular proliferation accompanying prominent eosinophilic infiltration. It is usually classified as a subset of angiolymphoid hyperplasia with eosinophilia despite of its peculiar
endothelial
morphology (i.e., vacuolization and hobnail appearance etc.). Histopathologically, the lesion was characterized by exuberant proliferation of capillaries, epithelioid-appearing endothelial cell, endothelial cytoplasmic vacuolization, solid sheets
of
endothelial cells, massive eosinophilic infiltration and lymphoreticular hyperplasia. The lesions are most common in the head-neck region and are characterized by single or multiple smooth-top papules or plaques of varying colors.
We report two cases of epithelioid hemangioma occurring on the left auricle and scalp. The chiet complaints were pruritus and they have been easily bleeding even in trivial trauma. Microscopically, the lesions were consisted of a proliferation of
small
to mediumsized blood vessels surrounded by inflammatory infiltrates predominantly composed of lymphocytes, histiocytes and eosinophils. The vessels were lined by epithelioid-appearing endothelial cells having enlarged round nuclei and abundant
eosinophilic or clear cytoplasm. Some vessels showed luminal obliteration by proliferating epithelioid endothelial cells. Occasionally, blood vessels were lined by hobnail-or scallop-shaped endothelial cells. In immunohistochemical findings, the
epithelioid endothelial cells of proliferated capillaries were immunoreactive to factor VIII-related antigen and negative to lysozyme.
(Kor J Dermatol 1992;30(5):727-736)
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