Bence Jones myeloma with a tetramer of kappa-type globulin in serum.

We describe a case of Bence Jones multiple myeloma involving two kappa-type monoclonal proteins. One was isolated from serum, the other from both serum and urine. After biochemical and immunochemical analyses, we concluded that one of the proteins was a tetramer, present in serum but not in urine, whereas the other was a monomer, which was excreted in large amounts in the urine during the terminal stage of the disease.