Extramammary Paget's Disease of the Perianal and Perineal Regions

A case of perianal and perineal extramammary Paget's disease in a male is reported. The presence of gross cystic disease fluid protein--a new marker of apocrine epithelia--in Paget's cells provides additional insight into the histopathogenesis of this condition. This marker may be a valuable diagnostic adjunct in evaluating intra-epithelial malignancies at a variety of anatomic sites.