Primary malignant lymphoma of the breast is a rare tumor, defined as a tumor localized in the breast with or without axillary lymph-node metastases. Such a tumor is mainly found in female patients and located more frequently in the right breast. It is difficult to make primary breast lymphoma (PBL) diagnosis before operation, and PBL diagnosis is mainly based on pathological biopsy and immunohistochemical staining. In this paper, the cases of three patients who had PBL, and who were treated for it at the Institute for Oncology and Radiology of Serbia between 2008 and 2012, are reviewed and discussed. These cases of PBL had no recorded reoccurrence of the disease and were originally treated by surgery, radiotherapy R-CHOP, and/or chemotherapy. While there is no consensus to the question of how to best treat PBL (ie, with chemotherapy, radiotherapy, or combined therapy), it is hoped that this review will offer insight into successful treatment procedures for tumors of this category.