Vulvar Paget's disease with an underlying sweat gland adenocarcinoma

Vulvar Paget's disease, in contrast to its mammary counterpart, has been found to be associated with an underlying apocrine sweat gland carcinoma in about only 1/4 of the cases. There are two principal theories regarding the pathogenesis of extramammary Paget's disease: (1) intraepidermal origin of the Paget cells occurring independently of, or concomitantly with, an underlying apocrine gland carcinoma, and (2) the migration or metastasis of Paget cells into the epidermis from the underlying apocrine glands and/or ducts. A case of vulvar Paget's disease that, in our opinion, supports the theory of apocrine gland origin of Paget cells is reported herein.