Alkaline phosphatase level in CSF in various brain tumors and pulmonary carcinomatous meningitis.

Twenty-six patients with various brain tumors or carcinomatous meningitis were examined for alkaline phosphatase (ALP) in the cerebrospinal fluid. ALP enzyme levels were compared with the respective levels in control groups of 75 patients with epilepsy, stroke, bacterial and viral meningitis and intervertebral disc prolapse. Extremely high ALP levels in CSF (9516 mu/l, 1425 mu/l, and 871 mu/l) were found in patients with pulmonary carcinomatous meningitis. Among all other patients with brain tumors, ALP levels in CSF were in the normal range. Examination of ALP in serum yielded normal results in all patients. In patients with pulmonary carcinomatous meningitis, the enzyme level in CSF was examined during various stages of radiotherapy and chemotherapy. Decreased ALP enzyme level was found during treatment followed by recurring rising levels a month after the treatment coinciding with clinical relapse. No correlation was found between the level of ALP enzyme and the biochemical and cellular content of the CSF during the various stages of treatment.