Bence Jones protein is a monoclonal globulin protein or immunoglobulin light chain found in the urine, with a molecular weight of 22–24 kDa. Detection of Bence Jones protein may be suggestive of multiple myeloma, or Waldenström's macroglobulinemia. Bence Jones proteins are particularly diagnostic of multiple myeloma in the context of target organ manifestations such as kidney failure, lytic (or "punched out") bone lesions, anemia, or large numbers of plasma cells in the bone marrow...