Multinucleate cell angiohistiocytoma. Report of five cases.

BACKGROUND: Multinucleate cell angiohistiocytoma is an infrequent and most likely non-neoplastic disorder usually seen in acral regions in elderly women. It presents clinically as asymptomatic red-to-brown tumors, with a tendency to confluence. It must be distinguished from other diverse cutaneous lesions, notably dermatofibroma, Kaposi sarcoma, and angiofibroma.

METHODS: We report the clinical, histopathological, and immunohistochemical findings of five patients, all women aged between 51 and 78 years. All except the first presented lesions on both of the lower limbs. None of the patients developed spontaneous resolution of the lesions and one was successfully treated by cryosurgery.

COMMENTS: Multinucleate cells are characteristic, but neither exclusive nor pathognomonic, of multinucleate cell angiohistiocytoma, since they can also appear in other inflammatory, neoplastic, or reactive processes. The presence of these cells and vascular proliferation in dermis media are the principal histopathological findings in this infrequent entity. In immunohistochemical studies, the multinucleate cells are often positive for vimentin and factor XIIIa.