A Case of Ductal and Lobular Carcinoma in Situ Arising within a Fibroadenoma

Abstract

A 74-year-old woman was diagnosed with a 12-mm invasive ductal carcinoma in the left BD region of the breast. She also had a well-demarcated mass measuring 15 mm in diameter located in the C region of her left breast. She underwent left total mastectomy with sentinel lymph node biopsy as treatment for invasive ductal carcinoma. Pathological examination revealed an invasive ductal carcinoma of the BD region (pT1cN0M0 stage IA) and ductal and lobular carcinoma in situ arising within the fibroadenoma of the C region. Although carcinoma within a fibroadenoma is rare, it is important to consider the possibility of carcinoma if unusual features are present in a tumor suspected to be a fibroadenoma. We report this case based on a literature review.