Abstract
Primary breast lymphoma (PBL) is a rare malignant entity, accounting for less than 0.5% of all breast malignancies. It must be differentiated from conventional breast carcinoma, as the therapeutic approach and outcomes differ. We present the case of an 86-year-old woman diagnosed with diffuse large B-cell non-Hodgkin lymphoma (NHL), non-germinal centre subtype, of the breast, whose only symptom was a palpable breast mass. The patient declined all proposed therapies. This case highlights the importance of considering breast lymphoma in the differential diagnosis of breast masses and emphasises the need for a multidisciplinary approach to ensure accurate diagnosis and appropriate management.