MULTINUCLEATE CELL ANGIOHISTIOCYTOMA - A DISTINCT ENTITY DIAGNOSABLE BY CLINICAL AND HISTOLOGIC FEATURES

Background: Multinucleate cell angiohistiocytoma is a newly described entity; examples from the United States have not yet been reported. Ob jective: Our purpose was to analyze the clinical and histologic featur es of this entity and confirm or refute its existence. Methods: Seven cases were analyzed clinically and by light microscopy. Results: Multi nucleate cell angiohistiocytoma typically occurs in middle-aged women and consists of multiple, grouped, red-brown to violaceous papules tha t are dome-shaped or flattopped, roundish and smooth in outline, sharp ly circumscribed, and occasionally coalescent. Typical sites are the l egs, thighs, and backs of hands and fingers. Microscopic features are an increased number of brood vessels (usually capillaries and venules) that are small, rounded, and not well grouped, together with multinuc leated histiocyte-like cells with scalloped borders. Conclusion: Multi nucleate cell angiohistiocytoma is a distinct entity that is diagnosab le clinically and histopathologically.