Plasma cell mastitis is a rare form of inflammatory, non-infectious, non-neoplastic, mastitis, not occurring during the post-partum and breastfeeding period. The pathogenesis of this lesion is not yet fully elucidated and an auto-immune origin is currently proposed. The common feature of this form of mastitis is the possibility of evolving towards recurrent aseptic abscesses. Treatment remains difficult and relapses are frequent with fistula formation to the skin, either spontaneously, or after surgery, even involving wide excision.