Cutaneous Rosai-Dorfman disease manifestating as recurrent breast tumor: a case report

A case of cutaneous Rosai-Dorfman disease (sinus histiocytosis with massive lymphadenopathy) manifestating as a recurrent breast tumor is reported. The tumor occurred on the left breast of a 35-year-old woman. Before arriving at the correct diagnosis, four biopsies had been performed with various diagnoses of chronic inflammation, plasma cell mastitis and inflammatory pseudotumor. Numerous typical histiocytes with lymphophagocytosis appeared in the final excised specimen, and a correct diagnosis was made. Ultrastructural examination revealed no evidence of Birbeck granule. The literature concerning Rosai-Dorfman disease manifestating as breast tumor is reviewed. Since the diagnosis is often overlooked in the absence of lymphadenopathy, a high index of suspicion is required to recognize this rare cutaneous Rosai-Dorfman disease.