Although the introduction of electrophoretic methods has led to a much improved characterization of the abnormal globulins which occur in patients with multiple myeloma, the simple determination of the presence of Bence Jones protein in the urine has remained as important as ever for the diagnosis of multiple myeloma. This remarkable thermolabile protein, with a molecular weight of 44.000, is present in 50 to 60% of patients with myeloma. Bence Jones protein must be distinguished from the myeloma globulins, with a molecular weight of 160.000 or greater, that are present in the serum. Irrespective of electrophoretic criteria, the diagnosis of Bence Jones protein in the urine must be accepted if a protein is present which precipitates between 45 and 60 C (113 and 140 F) and dissolves again between 90 and 95 C (194 and 203 F).
In our experience, the presence of Bence Jones protein proves the diagnosis of
Snapper I, Ores RO. DETERMINATION OF BENCE JONES PROTEIN IN THE URINE. JAMA. 1960;173(10):1137–1139. doi:10.1001/jama.1960.73020280014016