A clinical dilemma: malignant adenomyoepithelioma of the breast – case report and review of literature

Abstract

Malignant myoepithelioma of the breast is a rare lesion characterized by the malignant proliferation of the epithelial and myoepithelial cells that exhibit characteristic histological and immuno-histochemical features. Very few cases have been reported in literature. We report a case of a 64-year-old female with a palpable lump in the upper outer quadrant of her right breast, present for a number of years. She underwent lumpectomy under local anesthesia. Upon histological confirmation of the diagnosis of malignant myoepithelioma, the patient underwent wide local excision with sentinel node mapping. Malignancy was evident by extensive central infarction. The tumour was completely triple negative, i.e. Estrogen receptor (ER), Progesterone receptor (PR) and Human epidermal growth factor receptor 2 (HER2) negative. The patient also underwent adjuvant chemotherapy and radiation therapy. The patient remains well with no recurrence 7 years since her initial surgery. The authors believe, that due to the paucity of these rare tumours, optimal treatment strategies remain to be determined.

Fibromatosis-like metaplastic carcinoma: a case report and review of the literature

“…Houston, IARC; 2019, in press]. Both AME and FLMC show broad immunohistochemical overlap, however the pattern of staining of the CK AE1/AE3 marker might be helpful in the differential diagnosis because in AME, as opposed to FLMC, only the epithelial cells and not the (spindled) myoepithelial cells show expression with this marker [9,10]. FLMC and the majority of MBCs usually do not express ER, PR, HER2 [1,9], while AMEs can be ER-positive.…”

“…Given the spindle cell morphology, the presence of rare epithelioid cells, the mitotic activity, the clear co-immunoreactivity for CK AE1/AE3 and p63 and the triple-negativity for ER, PR and HER2, the differential diagnosis was limited to a borderline malignant ER-negative AME with myoepithelial overgrowth and LG-FLMC. Notably, a sharply delineated border and association with a centrally sclerotic region may be observed both in AME and LG-FLMC [3,10].…”