Extranodal multifocal Rosai-Dorfman disease of the breast: A case report.

We report a case of a 49-year-old female diagnosed with extranodal multifocal Rosai-Dorfman disease (RDD) of the breast using mammography and ultrasound. RDD is a rare non-Langerhans cell benign proliferative disorder of histiocytes that usually involves the lymph nodes, but may involve extranodal sites. We review the clinical presentation as well as imaging features of this rare disease on multiple modalities and the importance of recognizing the diagnosis in order to direct treatment.