Simultaneous Occurrence of Rosai-Dorfman Disease and Nodal Marginal Zone Lymphoma in a Patient with Sjögren's Syndrome.

We present an exceptionally rare case of co-occurrence of Rosai-Dorfman disease (RDD) and nodal marginal zone lymphoma (NMZL) in a 60-year-old Caucasian female with a 20-year course of Sjögren's syndrome (SS). In response to treatment for lymphoma, the patient presented a short positive response, followed by a rapid progression of the disease accompanied by the development of the peripheral facial nerve palsy. We failed to detect Epstein-Barr virus (EBV) in the NMZL/RDD sample by EBV-encoded RNA (EBER) in situ hybridization but identified genomic DNA of EBV by polymerase chain reaction.