Abstract
Primary breast lymphoma (PBL) is an uncommon type of breast malignancy. Its clinical presentation and radiographic findings are non-specific and overlap with breast carcinoma. The treatment of PBL differs significantly from breast carcinomas. Here we present a middle-aged woman who presented with an enlarging palpable right breast mass. Mammogram showed breast imaging-reporting and data system 4 findings. Breast mass biopsy pathology confirmed diffuse large B cell lymphoma. Although uncommon, clinicians should be cognisant of the possibility of PBL when patients present with a breast mass. Accurate diagnosis is essential to avoid unnecessary mastectomies.