Lymphoepithelioma-Like Carcinoma of the Breast: A Case Report of a Rare Type of Invasive Carcinoma.

Lymphoepithelioma carcinoma (LELC) is an extremely rare type of mammary cancer. Based on the histology, it can be misdiagnosed with inflammatory lesions like mastitis and medullary carcinoma or other hematopoietic neoplasms like lymphoma in the breast. Since LELC has a good response to chemotherapy with a good prognosis, t is prognostically important to recognize LELC. We report a rare case of LELC in a 51-year-old pre-menopausal female with a left breast mass, diagnosed with invasive ductal carcinoma (IDC), LELC type, treated with mastectomy, followed by adjuvant chemotherapy and radiotherapy, with a disease-free interval of 10 months. Herein, we present the case with its clinical presentation, radiologic imaging, histopathological features, and immunohistochemistry (IHC) findings. The rarity of this type of breast tumor warrants studying the behavior of these uncommon tumors to avoid misdiagnosis and establish well-defined criteria for diagnosis.