[Part I. Theory and computer simulation for cerebrospinal infusion].

A pharmacokinetic one-compartment model for the cerebrospinal infusion for the brain tumor chemotherapy is described together with various parameters used for computer simulation. An antitumor protein, neocarzinostatin (NCS) as a prototype drug, has been utilized since it was found effective against glioblastoma cells at extremely low concentration (less than 5 ng/ml) and it is readily inactivated by serum. A very slow infusion velocity was found necessary for an appropriate dose regimen; for example, 0.25mg of the drug should be infused into CSF for about 40 min to attain a drug level of 8 ng/ml.