Abstract
Adnexal tumors on the vulva do occur but less frequently compared to other anatomic sites. Histopathologically, they are identical to neoplasms occurring elsewhere on the integument and presumably have the same histogenesis.
However, some lesions that are traditionally classified under the rubric of cutaneous adnexal neoplasms appear to be specific for the vulva and are histogenetically associated with specific anatomic structures named anogenital mammary-like glands (AGMLG). The latter resemble breast tissue and have long been considered as such, namely, to represent ectopic breast tissue.
Recent research however demonstrated that AGMLG represent a normal constituent of the anogenital area, and the vulva in particular. Lesions originating in AGMLG, benign or malignant, epithelial or stromal, manifest a striking similarity to their mammary homologues.
Discussed in this -chapter, the most common lesions thought to be associated with AGMLG, including hidradenoma papilliferum, fibroadenoma, phyllodes tumor, extra-mam-mary Paget disease, and some other less common entities.