Rapid Local Recurrence of Breast Myoepithelial Carcinoma Arising in Adenomyoepithelioma: A Case Report.

Adenomyoepithelioma (AME) is a rare breast neoplasm composed of both epithelial and myoepithelial cells with biphasic proliferation. Although most AMEs are benign, malignant transformation of either or both cellular components may occur. This report describes an unusual rapid local tumor recurrence a month after excision of the myoepithelial carcinoma arising in an AME. Ultrasound and MRI showed small recurrent masses in the superficial part of a hematoma. This report suggests the benefit of immediate postoperative breast imaging in patients with malignant AME with potential for local recurrence, such as those with narrow resection margins or high mitotic activity.