Epithelioid haemangioendothelioma of the breast

This article describes histopathologica, immunohistologic, and morphometric features of an epithelioid haemangioendothelioma that presented in the bre ast of a 30-year-old woman. Histologically the tumour was composed of large round, polygonal, slightly spindle shaped endothelial cells lying in a myx oid matrix. The lesion exhibited primitive vasoformation characterized by t he presence of cytoplasmic vacuoles. The tumour cells reacted positively to F-VIII related antigen, whereas mammary ducts entrapped by the tumour cell s reacted positively with keratin. Although the breast is an unusual locati on for this type of lesion, epithelioid haemangioendothelioma should be con sidered a rare differential diagnosis of a breast mass. (C) 1999 Harcourt P ublishers Ltd.