[Diabetic mastopathy].

Background: Diabetic mastopathy is a rare condition, which is clinically not easily to differentiate from breast cancer.

Case Description: A 32-year-old woman, with a long-standing history of insulin-dependent diabetes mellitus presented at the breast outpatient clinic with a firm palpable, painless mass in her right breast. Mammography and ultrasound examination showed, respectively, slight asymmetry with dense glandular tissue and a hypoechoic area with posterior shadowing. MR mammography showed no suspicious abnormalities. Histopathological examination revealed fibrous tissue with lymphocytic inflammation. The combination of clinical presentation, history of diabetes mellitus, and histological findings led to a diagnosis of diabetic mastopathy.

Conclusion: A palpable breast abnormality in a woman with diabetes mellitus can be caused by diabetic mastopathy. Knowledge of this condition by the disciplines involved can prevent over-diagnosis and unnecessary interventions.