Two cases of inflammatory bowel disease with multiple myeloma.

A significant increase has been reported in reticuloendothelial neoplasms in patients with inflammatory bowel diseases. We present two rare cases of multiple myeloma in patients with inflammatory bowel diseases. One was in a 58-year-old woman with ulcerative colitis, and the other was in a 59-year old woman with Crohn's disease. In both patients, multiple myeloma occurred during long-term observation of inflammatory bowel disease and during the inactive stage of intestinal inflammation. The multiple myeloma appeared to have resulted from monoclonal gammopathy of undertermined significance in both patients, and was diagnosed by characteristic serum and bone marrow findings. Our findings suggested that multiple myeloma should be particularly considered in women of middle or advanced age with ulcerative colitis or Crohn's colitis and serum monoclonal gammopathy.