Digital Atlas of Breast Pathology by Meenakshi Singh, MD © - Department of Pathology, Stony Brook University Medical Center

Cellular fibroadenoma.
Cellular fibroadenoma, also known as juvenile fibroadenoma, usually occurs in patients under the age of 20. The lesion shows a proliferation of stromal and epithelial proliferation. These ducts are not compressed by stroma, and this lesion is described as having a pericanalicular pattern.