Beta 2 microglobulin is a low molecular weight
protein integrating the light chain
HLA antigens. Its serum concentration is increased in different
neoplasias and in
renal failure. Using solid phase RIA we determined the concentration of
beta 2 microglobulin in plasma and spinal fluid of 57 healthy individuals and patients with hematologic
neoplasia. Serum levels were 1.34 +/- 0.34 mg/l and spinal fluid levels were 1.3 +/- 0.7 mg/l in healthy subjects. Serum levels in 29 patients with myeloma was 7.51 mg/l, significantly higher in those with
renal failure (12.35 mg/l) compared to those without (4.54). In 30 patients with
non-Hodgkin lymphoma the mean serum levels were 2.90 mg/l, significantly greater in those with active disease (3.18) than in those with remission (1.5). No difference was found according to the degree of
malignancy. Patients with acute lymphatic
leukemia had elevated values of
beta 2 microglobulin while the disease was active (3.37 mg/l), decreasing to normal levels after remission (1.79 mg/l). Spinal fluid levels of
beta 2 microglobulin were elevated only in patients with central nervous system involvement. Our results indicate that serum levels of
beta 2 microglobulin are helpful in patients with hematologic
neoplasia in assessing the activity of the disease and
tumor mass, especially in
multiple myeloma.