**3. Conclusion**

Glioblastoma is currently not curable and the prognosis of it is very poor. A world-wide standard care of newly-diagnosed GB is postoperative XRT with concomitant and adjuvant chemotherapy with new alkylating agent TMZ(Stupp et al. 2005). This standard treatment for newly diagnosed GB prolonged the median ST of patients from 12.1 months to 14.6 months in comparison with XRT alone, which is still pessimistic clinical result of this disease. Therefore an alternative promising treatment should be developed for the improvement of the prognosis of newly diagnosed GB. Several recent clinical studies on the treatment of patients with GB by means of BNCT have reported encouraging results. Careful analysis of survival data from a study, carried out in Sweden (Skold *et al.*) in which BPA was administered at a higher dose over a longer period of time (Skold *et al.*), suggested that a subset of patients had survival times that were at least as good as those obtained with conventional therapy consisting of X-irradiation in combination with TMZ (Stupp et al. 2005).

On the other hand, BNCT is tumor-selective particle radiation. Tumor-seeking boron compounds boronophenylalanine (BPA) and sodium borocapate (BSH) can be delivered selectively in GB tissue with high contrast of accumulation in comparison with normal brain tissue. This tumor selective accumulation of boron compounds is followed by neutron irradiation, which produced high linear energy transfer particles (alpha particle and recoiled Li nucleus). Thereafter these particles can destroy tumor cells selectively with high efficiency (Barth et al. 2005). The principal investigator of this clinical trial published the excellent survival data of 21 cases of newly diagnosed GB treated by BNCT with the MST of 15.6 months without TMZ. Moreover additional 20 to 30Gy XRT prolonged the MST up to 23.5 months in 11 cases without TMZ (Kawabata *et al.* 2009b). These strategies were also confirmed by pre-clinical bench works (Barth *et al.* 2004). These are the background of our on-going clinical trial. Thereafter in this trial, the protocol is composed of BNCT, followed by 24Gy XRT with concomitant and adjuvant chemotherapy with TMZ for newly diagnosed GB patients.
