Boron Neutron Capture Therapy of Cancer1

brain tumors. Shortly thereafter, a clinical trial was initiated at the Brookhaven National Laboratory in cooperation with Sweet and others at the Massachusetts General Hospital utilizing borax as the capture agent (5, 6). The objective at that time was to use BNCT as an adjunct to surgery for the treatment of patients with the most highly malignant and therapeutically refractory of all brain tumors, glioblastoma multiforme. Further trials were carried out in the early 1960s, but as will be described in more detail later on, these failed to show any evidence of therapeutic efficacy (5-7) and were associated with adverse effects in normal tissues (7). Stimulated by the more encour aging clinical studies of Hatanaka et al. (8, 9) for the treatment of malignant gliomas and those of Mishima et al. (10) for melanoma, there has been renewed national and international interest in BNCT. The theoretical advantage of BNCT is that it is a two component or binary system, consisting of 10Band