Cerebrospinal fluid beta-2-microglobulin level as marker of central nervous system involvement in lymphoma.

The cerebrospinal fluid (CSF) and serum beta-2-microglobulin (B-2-m) level was determined in 15 patients affected by lymphoma with and without central nervous system (CNS) involvement and in 15 normal controls. No statistical difference in CNS B-2-m was found between patients affected by lymphoma without CNS involvement and normal subjects. CSF B-2-m was significantly increased (p less than 0.001) in patients with CNS involvement as compared to normal subjects or patients without CNS involvement. These findings suggest that CSF B-2-m can be used as a useful marker of CNS involvement in patients affected by lymphoma.