Pharmacokinetics of superselective intra-arterial and intravenous [11C]BCNU evaluated by PET.

The pharmacokinetics of i.v. and superselective intra-arterial carbon-11 1,3-bis-(2-chloroethyl)-1-nitrosourea ([11C]BCNU) were directly compared for the first time in ten patients with recurrent gliomas using positron emission tomography (PET). Intra-arterial administration of [11C]BCNU achieved concentrations of the drug in the tumor that averaged 50 times higher than with a comparable i.v. dose. These preliminary results suggest that the degree of early metabolic trapping of BCNU in tumor correlates with the clinical response to this chemotherapy.