Two Cases of Malignant Breast Adenomyoepithelioma Treated with Neoadjuvant Chemotherapy

Abstract

An adenomyoepithelioma is a benign tumor in which both glandular epithelial cells and myoepithelial cells proliferate. In rare instances, a malignant adenomyoepithelioma, in which either or both cells become malignant, may develop. In this study, we present two such cases of malignant breast adenomyoepithelioma treated with neoadjuvant chemotherapy and a relevant literature review. Case 1 was of a 32-year-old woman who presented with the chief complaint of a mass exceeding 5 cm in the left breast. A needle biopsy revealed an invasive ductal carcinoma, and she was diagnosed with a T3N1M0 stage IIIA for which neoadjuvant chemotherapy was administered. Following mastectomy and axillary lymph node dissection, postoperative histopathological examination revealed a malignant adenomyoepithelioma, requiring further chemotherapy and hormone treatment. The patient was healed and remains alive and without recurrence 6 years and 4 months after the surgery. Case 2 was of a 73-year-old woman in whom a thorough examination revealed a 15-mm mass in the left breast. A needle biopsy indicated an invasive, triple negative, ductal carcinoma. Neoadjuvant chemotherapy was performed, as well as a mastectomy and sentinel lymph node biopsy. Here too, a postoperative histopathological examination revealed a malignant adenomyoepithelioma. In this case, capecitabine was administered postoperatively, and the patient remains alive and without recurrence 1 year after the surgery.