Cerebrospinal fluid beta 2-microglobulin: a study in controls and patients with metastatic and non-metastatic neurological diseases.

We studied cerebrospinal fluid Beta 2-microglobulin (CSF B2-m) in 197 patients with a variety of neurological diseases to evaluate the usefulness of B2-m in the detection of meningeal dissemination of malignancy. In the control group we found a relationship between CSF log B2-m and age (P less than 10(-4)). Age standardized reference values were established as 0.65-2.2 mg/l. The results show that CSF B2-m was elevated in leptomeningeal metastases from solid and haematological tumors. We observed slight elevations of CSF B2-m in epidural and parenchyma metastases from solid tumors. Our study shows that B2-m in CSF is a sensitive marker for meningeal metastases especially from hemopoietic tumors.