Medical aspects of boron-slow neutron capture therapy

Earlier radiations of patients with cerebral tumors disclosed the need: (1) to find a carrier of the boron compound which would leave the blood and concentrate in the tumor, (2) to use a more penetrating neutron beam, and (3) to develop a much faster method for assaying boron in blood and tissue. To some extent number1 has been accomplished in the form of Na2 B12 H11 SH, number2 has yet to be achieved, and number3 has been solved by the measurement of the 478-keV gamma ray when the 10B atom disintegrates following its capture of a slow neutron. The hitherto unreported data in this paper describe through the courtesy of Professor Hiroshi Hatanaka his studies on the pharmacokinetics and quality control of Na2 B12 H11SH based on 96 boron infusions in 86 patients. Simultaneous blood and tumor data are plotted here for 30 patients with glioblastomas (Grade III-IV gliomas), illustrating remarkable variability. Detailed autopsy findings on 18 patients with BNCT showed radiation injury in only 1. Clinical results in 12 of the most favorably situated glioblastomas reveal that 5 are still alive with a 5-year survival rate of 58% and the excellent Karnofsky performance rating of 87%. For the first time evidence is presented that slow-growing astrocytomas may benefit from BNCT. 10 references, 8 figures, 5 tables