Diabetic mastopathy (DM) is an unusual fibrous disease of the breast. We report 34 cases with clinicopathological correlation and follow-ups. Patients mean age was 57 years and 24 had histories of diabetes mellitus. The DM presented as a palpable breast mass in 85.3% of the cases clinically. Image findings were often as an irregular hypoechoic mass (44.4%) on ultrasound and negative or non-specific density (67.6%) on mammogram. Histologically, we found that the majority of DM occurred in the upper outer/central part of the breast (76%) and the size ranged from 0.5 to 3.7 cm. All cases showed lymphocytic lobulitis and vasculitis, keloidal fibrosis, lobular atrophy and varying degree of epithelioid fibroblasts. Examining the surrounding normal tissue of the excision specimens revealed that the margins of DM were often poorly circumscribed and irregularly demarcated from the sounding breast tissue. Vascular calcifications were identified in 10 of 24 excisional specimens, suggesting a hypothesis that vascular damage and scar/wounding healing process could contribute to the pathogenesis of DM. Twenty-one cases had repeated procedures for uncertain descriptive diagnosis. This is the largest study of diabetic mastopathy to date with clinical and imagining correlation. Recognition of this benign entity is important to better understanding the pathogenesis and to avoid unnecessary procedures.
© 2012 The Authors. Pathology International © 2012 Japanese Society of Pathology and Wiley Publishing Asia Pty Ltd.