Fibroadenoma (FA) of the breast is a benign fibroepithelial lesion rarely showing atypical epithelial overgrowth. We present case 50-year-old Japanese woman with sclerotic FA ductal hyperplasia (ADH)/ductal carcinoma in situ (DCIS). A small mass was detected during clinical examination upper lateral area left breast. Hematoxylin and eosin stain section needle core biopsy specimen showed trabecu...