Autoimmune Mastitis in a Patient with Behcet's Syndrome: A Case Report with Rapid Changes in Radiologic Features and Characteristic Pathologic Findings.

Breast manifestations of autoimmune diseases are rare but may present as localized disease or as part of a systemic disease. The most common clinical presentations of autoimmune mastitis are palpable masses and mastalgia, but patients can also be asymptomatic. Its radiological features are nonspecific and varied; it usually appears as an irregular hypoechoic mass or ill-defined hypoechoic nonmass lesion that mimics malignancy, with or without duct ectasia on breast ultrasonography. On breast MRI, segmental or regional nonmass enhancement is observed. However, due to its nonspecific and rapid changes in its clinical and radiological features, its diagnosis is often challenging and delayed. Herein, we present a rare case of mastitis with mammary duct ectasia in a patient with Behcet's syndrome and its rapid changes in imaging features on serial radiologic studies. Furthermore, we review the literature focusing on the radiologic and histopathologic characteristics of autoimmune mastitis.