Combination of Adenomyoepithelioma and Adenoid Cystic Carcinoma of the Breast: A Case Report of an Uncommon Histopathological Entity.

BACKGROUND Adenomyoepithelioma and adenoid cystic carcinoma are uncommon types of breast tumors. Adenoid cystic carcinoma accounts for 0.1% of breast neoplasms and typically presents as a tender breast tumor, mostly in the subareolar area. Adenoid cystic carcinoma usually appears in women in the fifth or sixth decade of life and predominantly presents as a mixed tumor, with cribriform, tubular, and solid growth characteristics. Adenomyoepithelioma of the breast shows epithelial and smooth muscle characteristics. Adenomyoepithelioma rarely goes through malignant transformation and is an uncommon type of benign breast tumor. CASE REPORT Our study reviews the current published literature regarding the combination of these 2 rare neoplasms of the breast and shows a rare case of a 48-year-old woman with a combination of adenoid cystic carcinoma and adenomyoepithelioma. CONCLUSIONS The combination of adenoid cystic carcinoma and adenomyoepithelioma should be part of the differential diagnosis in breast cancer. More research is needed regarding the optimal therapy, which is currently surgical excision.