Adenomyoepithelioma with carcinoma of the breast: A report of two cases and a review of the literature

We herein described two cases of adenomyoepithelioma (AME) with carcinoma of the breast. Both of them were Japanese women, and they presented with a mass in their breast. Post-operative specimens revealed encapsulated and well-circumscribed tumors with local invasion, necrosis, cytological atypia, and a high mitotic rate. In immunohistochemistry, coincidentally with the loose adhesion pattern of myoepithelial cells in both cases, the intensities of E-cadherin and beta-catenin were much weaker in myoepithelial than luminal epithelial cells, with almost negative finding of beta-catenin in one case. We first found deletion of CDH1 and polysomy of CEP16 in myoepithelial cells by double color-fluorescence in situ hybridization. The two cases have been followed up for 5–8 years, and both remained free from local recurrence and distant metastases. We also presented an overview of 47 cases of AME with carcinoma in English-language literatures.