Boron neutron capture therapy: boron biodistribution and pharmacokinetics of Na2B12H11SH in patients with glioblastoma.

Data on biodistribution and pharmacokinetics of Na2B12H11SH are few and lack in standardization. This study comprises a uniform series of 10 patients with glioblastoma administered Na2B12H11SH i.v. 24 h before surgery at a dose level used in earlier therapeutical trials (75 mg/kg body weight). Boron concentrations in tumor, normal brain, peritumoral edematous brain, blood, and urine were determined by inductively coupled plasma-atomic emission spectroscopy 24 h after Na2B12H11SH administration; boron uptake in tumor (mean, 12.2 micrograms/g) was sufficiently selective compared to concentrations in normal and edematous brain (1.2 and 2.3 micrograms/g, respectively). Mean concentration ratio of tumor:blood was slightly above unity. Boron concentration in blood decreased according to an open two-compartment model, mean excretion in urine over 24 h was 81.9%. The only side effect was an inconstant facial flush. Among efforts aiming at an optimized treatment protocol a dose escalation study seems to be justified.