{Reference Type}: Journal Article {Title}: IgG4-related mastitis characterized by skin thickening of the breast: a case report. {Author}: Itakura M;Horimoto Y;Ishizuka Y;Onagi H;Hayashi T;Kawamoto T;Watanabe J;Iijima K; {Journal}: Surg Case Rep {Volume}: 9 {Issue}: 1 {Year}: 2023 Nov 1 暂无{DOI}: 10.1186/s40792-023-01770-0 {Abstract}: BACKGROUND: IgG4-related diseases are characterized by marked infiltration and IgG4-positive plasma cells and fibrosis, and involve multiple organs. However, IgG4-related mastitis is rare. We report a case of mastitis associated with IgG4-related disease.
METHODS: A 78-year-old woman visited our hospital with a complaint of multiple subcutaneous nodules. A biopsy of a dorsal subcutaneous mass was performed but did not yield a definitive diagnosis. However, blood tests showed a high level of IgG4, thus she was referred to the department of collagen disease for further examination. Computed tomography (CT) showed a thickening of the skin of the right breast, and the patient was referred to our department. On physical examination, a large area of thickened skin was observed in the right breast without inflammatory breast cancer-like redness, and no mass was palpable. A needle biopsy was performed on an indistinct hypoechoic area in the breast, and she was diagnosed with mastitis associated with IgG4-related disease. Systemic steroid therapy was then administered and the symptoms of multiple skin nodules and mastitis improved.
CONCLUSIONS: We reached the diagnosis based on a biopsy of the mammary gland enabling the patient to begin treatment for IgG4-related disease. This case was characterized by breast skin thickening, which is different from inflammatory breast cancer.