Lymphoepithelioma-like carcinomas (LELCs) are tumors with morphologic features identical to those of undifferentiated nasopharyngeal carcinoma. They are characterized by a pronounced lymphocytic infiltrate, often obscuring the neoplastic epithelial component. LELCs have been described in several organs, but are extremely rare in the breast. In this report, two cases of LELC of the breast are presented with their histological and immunohistochemical features. In situ hybridization for Epstein-Barr viral genome was negative in both cases. We discuss the differential diagnosis of LELC of the breast and review the reports of this entity that have appeared in the literature. (C) 2004 Elsevier Ltd. All rights reserved.