Erosive Nipple Adenomatosis

**Semantic type:** Neoplastic Process

**Definition:** A rare benign neoplasm that arises in the area of the nipple. Clinically, it usually presents as a tender erythematous crusting lesion with hardening of the nipple. Morphologically, there is proliferation of ducts lined with epithelial and myoepithelial cells and focal erosion of the epidermis.