Lymphoepithelioma is a rare clinical entity, first was described in nasopharynx, and have been reported in another organs. Lymphoepithelioma-like carcinoma (LEC) of the breast is an undifferentiated carcinoma. Approximately 32 cases have been described, and differential diagnoses include primary breast lymphoma and medullary carcinoma. We present a 57-year-old woman, diagnosed with LEC of the breast, treated with mastectomy, followed by adjuvant chemotherapy, radiotherapy, and hormone therapy, with a disease-free interval of 2 years. There is scarce evidence related to the best treatment choice in this histological type.
Keywords: Breast; Epstein–Barr virus; lymphoepithelioma-like carcinoma; lymphoma.