Background: Epithelioid hemangioma (EH) is a benign vascular proliferation usually accompanied by a mixed inflammatory infiltrate.
Methods: Skin biopsy specimens from four patients with EH on the extremities were studied. Architecture, extent of vascular proliferation and the presence of epithelioid endothelial cells were evaluated. The features of the inflammatory infiltrate were also assessed, including the distribution, depth, predominant cell type, presence of germinal centers, and distribution and number of CD30+ cells.
Results: All cases showed the typical lobular pattern of small vessels centered about a 'feeder' vessel. Larger vessels were lined by epithelioid endothelial cells. The mixed inflammatory infiltrate was nodular, perivascular and periadnexal. Germinal centers were seen in two cases. Large activated CD30+ lymphocytes were seen in all cases.
Conclusions: EH can lead to diagnostic confusion with cutaneous lymphoma and other entities, especially when its mixed inflammatory infiltrate predominates over its vascular component and contains large activated CD30+ lymphocytes. Awareness that the presence of CD30+ activated lymphocytes is not specific for lymphoma and recognition of the vascular component is critical for proper diagnosis of EH.