Plasmacytoid mastitis is a specific type of chronic nonbacterial inflammatory lesion that is commonly seen in women 2 to 5 years postpartum and with nipple indentation, manifesting as breast lumps with inflammatory-like manifestations and accompanied by periareolar abscesses and areolar duct fistulas. Plasmacytoid mastitis and granulomatous mastitis, collectively known as non-lactating mastitis, are two seemingly different sisters, with unknown causes, difficult to treat, and prone to recurrence, causing great pain to patients. An enlarged radial incision is also possible to remove the inflammatory lesion and part of the necrotic skin, and to correct the nipple invagination at the same time. Stage I healing was achieved in all cases. Glandular flap transfer was performed in cases with large lesion excision to avoid mastectomy alone. Patients with ductal fistulae as the main manifestation: fistulae located around the areola, multiple complex fistulae, all patients were guided by probes, fistulae and surrounding tissues were excised, and nipples were incised. All cases were healed at stage I. 3. Patients with breast abscess as the main manifestation: incision and drainage followed by surgery, or direct surgery, can generally achieve stage I healing, and a few patients have a little exudate in the wound, which heals after drainage and drug exchange. 4.Duct dilatation type: all are recurrent, simply remove the lesion, combined with nipple invagination or nipple dysplasia, perform nipple exenteration and split the nipple, all cases are stage I healing. 5. Patients with multiple clinical manifestations: treatment was individualized according to the clinical manifestations of the patients, and glandular flap transfer was performed at the same time due to the large extent of lesion excision.