The clinical significance of recognizing distinct morphologic features of systemic diseases on breast biopsies.

Prominent lymphocytic periductal inflammation has been previously described in association with diabetes mellitus type I and II, other autoimmune diseases such as lupus, thyroid disease, and connective tissue abnormalities, and even lymphomas. When incidentally detected in a breast biopsy and without evidence of systemic disease in the patient's history, it may be prudent to alert the treating clinician to the possibility of an underlying systemic disease process, in order to ensure recognition and appropriate clinical follow-up for these patients. The purpose of this review is to familiarize the reader with this commonly encountered incidental feature on breast biopsies and to emphasize the importance and clinical implications of recognizing possible underlying systemic disease and communicating these findings to the treating physicians.