Diagnosis of Leukemia or Lymphoma in the Central Nervous System by Beta2-Microglobulin Determination

Abstract

To detect early relapse in the central nervous systems (CNS) of patients with acute leukemia or lymphoma, we measured levels of beta₂-microglobulin (β₂m) in serum and cerebrospinal fluid (CSF). CSF levels were significantly higher in patients with leukemia (P2m was significantly higher than the serum level in patients with acute leukemia and lymphoma with CNS involvement (P = 0.05), but not in patients without CNS involvement. Serial determination of CSF β₂m correlated well with the clinical appearance and disappearance of CNS involvement. These data suggest that serial and simultaneous determination of β₂m in serum and CSF may be useful in early diagnosis of CNS involvement and in monitoring intrathecal therapy in patients with acute leukemia or lymphoma. (N Engl J Med. 1980; 303:718–22.)