Extramammary Pagetʼs disease—Evidence for an apocrine origin

Abstract

The histogenesis of extramammary Paget''s disease has long remained unresolved and controversial. In an attempt to delineate the origin of the neoplastic cells in this disease, the immunoperoxidase localization of gross cystic disease fluid protein (GCDFP-15), a marker of apocrine epithelium, carcinoembryonic antigen (CEA) and keratin proteins, was determined for 7 [human] cases of extramammary Paget''s disease (5 vulvar, 1 anogenital and 1 axillary). Immunoreactivity for GCDFP-15 was localized within Paget cells in 6 of 7 cases, including 5 cases from the vulva and 1 case from the axilla. CEA was present in the Paget cells in all 7 cases. None of the Paget cells exhibited immunoreactivity for keratin proteins. Within normal skin, eccrine glands were immunoreactive for both keratin and CEA, whereas GCDFP-15 localized only to apocrine ducts and glands. An apocrine cell derivation for extramammary Paget''s disease is supported.