label: Breast Atypical Ductal Hyperplasia
label_lc: breast atypical ductal hyperplasia
description: "A neoplastic process that arises from the terminal ductal lobular unit of the breast parenchyma.  It is usually solitary and confined to a single lobular unit.  It is characterized by the presence of a monomorphic epithelial proliferation in a cribriform, micropapillary, or solid growth pattern.  Focal architectural features of low grade ductal carcinoma in situ are present.  There is an increased risk for development of invasive breast carcinoma."