Bilateral, tumorlike diabetic mastopathy-progression and regression of the disease during 5-year follow up.

Diabetic mastopathy is a recently described collection of radiographical and histological features found in dense fibrous masses of the breast in long standing Type I diabetes. We describe the first case of bilateral disease with the alternate progression and regression of the disease over a 5 year period. A 45-year-old woman has been affected of insulin dependent diabetes mellitus (IDDM) for 21 years. She developed palpable mass retromamillar of the right side, indistinguishable radiographically from cancer. The histology showed a diabetic mastopathy (DMP) with B-lymphocytic ductitis and lobulitis, a discrete monocellular vasculitis and a keloid-like fibrosis. After 22 months she developed a suspicious palpable mass contralateral on the left side. The FNAB presented an identical morphology on histology. Additionally 10 months later there were no palpable masses of both mammae. Mammographically no suspect alterations were observed. One year later the clinical and mammographical examination showed similar findings, mentioned before. The pathogenesis is still obscure and includes the hypothesis of extracellular accumulation, secondary to prolonged hyperglycemia in IDDM, production of alternated non-enzymatic glycosylated end products with neoantigen formation, B cell predominant inflammation with autoimmune response against neoantigens and cytokine release secondary to the autoimmune response.