Abstract

Plasma Cell Mastitis (PCM) is a benign breast entity that occurs in females in middle age with main histopathological characteristic-infiltration of plasma cells and lymphocytes in breast tissue. The importance of PCM lies in his similarity to the breast cancer in a clinical, microscopical and macroscopical presentation. Different stages of the PCM can resemble different diseases, such as tuberculosis, periductal mastitis, inflammatory and ductal breast carcinoma. A 35-year-old woman was presented with a subareolar firm mass in the right breast, 5 cm in size, followed by nipple discharge and retraction, which clinically mimicked breast carcinoma. The patient was treated surgically. We detected centered or subareolar dilated ducts, with fibrous thickening of the wall and foamy macrophages. The sections are composed of fibro-fatty tissue, with areas of indurations that contained hyperemic capillaries and granulocytic-eosinophilic leucocytes. The exudate contained thick-tan-yellow colored secretion, cholesterol crystals, “lipophagic polyps” and calcification. Intraductal epithelium was atrophic, dysplastic with papillomatosis or squamous metaplasia. Late lesions of periductal fibrosis and “Gareland pattern” were reported. Unclear etiology of PCM, mimicking of the other granulomatous lesions and challenges in diagnosis and treatment, as described in the literature, were observed in our case. Our aim was to present rarity of the disease and challenges in the diagnosis and treatment.

Keywords: Plasma cell mastitis; Breast cancer; Diagnosis; Treatment; Mimicking