Diabetic mastopathy in type II diabetes mellitus.

Diabetic mastopathy can mimic cancer. We report 2 cases of diabetic mastopathy in patients with long-standing type II diabetes. One was insulin-dependent, and the other had never been treated with insulin. These 2 patients had classical acoustical shadow on ultrasonograms. Breast core biopsies showed constellations of morphological features resembling diabetic mastopathy, including sclerotic changes of the fibrous stroma with keloid-like collagen fibers, few epithelioid fibroblasts, perivascular and interlobular mononuclear cell infiltrates, and focal atrophic changes of the ductal-lobular units. Both patients were free of malignancy at 3 and 4 years of follow-up, respectively. There are limited data on diabetic mastopathy in insulin-naive type II diabetes mellitus patients. Better awareness of this entity and its sonographic features may allow more patients to be spared from excisional biopsy.