A small cohort of MGMT non-methylated patients with residual tumour showed PFS of 6.2 versus 4.0 months ( HR , 0.77 ; 95 % CI , 0.35-1 .67 ; P = 0.4997 ) and OS of 19.0 versus 13.8 months ( HR , 0.66 ; 95 % CI , 0.27-1 .64 ; P = 0.3648 ) .