Atypical ductal hyperplasia involving a papilloma Note the thin fibrovascular cores in the upper left corner. The proliferating epithelium shows cytologic features of DCIS (monotonous nuclei) but does not fulfill the architectural criteria for carcinoma
in situ, as the nuclei are overlapping and cell borders are
indistinct. It is therefore classified as atypical ductal
hyperplasia.
Digital Atlas of Breast Pathology by Meenakshi Singh, MD © - Department of Pathology, Stony Brook University Medical Center