Sjögren's syndrome terminating with multiple myeloma.

We describe a patient (49 years old, female) with a more than 7-year history of both Sjögren's syndrome (SjS) and benign monoclonal gammopathy (BMG) of IgG lambda who later developed multiple myeloma (MM). SjS is frequently complicated with malignant lymphoproliferative disorders, especially malignant lymphoma or Waldenström's macroglobulinemia. Association of SjS with MM seems to be extremely rare, although BMG has been observed frequently in SjS, and there are many reports concerning the association between rheumatoid arthritis and MM.