Diabetic mastopathy is an unusual lesion consisting of a lymphocytic mastitis with acinar atrophy. Dense sclerosis is another component of the lesion.
Periductal lymphocytes are present in variable density among different ducts.
The atrophic ducts are scant, embedded in a uniformly dense background of acellular to hypocellular sclerosis.
This marked sclerosis results in a palpable mass, which is then brought to clinical attention because of the resemblence to malignancy.
Many fields are devoid of epithelium, consisting of large zones of wavy collagen. A few epithelioid fibroblasts may be appreciated.
This uncommon form of chronic mastitis arises in diabetics, typically those with longstanding type I. On occasion there is no history of diabetes and some patients have type II diabetes.
A discrete nodule or diffuse nodularity is palpable on exam, predominantly in the subareolar region.
Biopsy proven recurrences have been documented on long term follow-up in 32% (Ely). Recurrences can be ipsilateral, contralateral, or bilateral.
Ely KA, et al. Diabetic mastopathy. A clinicopathologic review. Am J Clin Pathol. 2000 Apr;113(4):541-5.