CTLA4 and neoplasm: Among the antibodies tested, an anti-CTLA-4 antibody significantly increased the anti-tumor efficacy of irradiation, with the TGD extended from 13.1±2.3 (irradiation alone group) to 19.5±2.9 (anti-CTLA-4 antibody plus irradiation group) days (p<0.005; Fig. 6A).