In the per-protocol population ( n = 320 ) , WBRT nonsignificantly prolonged progression-free survival ( PFS ) ( median 18.2 vs 11.9 months , hazard ratio [ HR ] 0.83 [ 95 % confidence interval ( CI ) 0.65-1 .06 ] , p = 0.14 ) and significantly PFS from last HDMTX ( 25.5 vs 12.0 months , HR 0.65 [ 95 % CI 0.5-0 .83 ] , p = 0.001 ) , but without OS prolongation ( 35.6 vs 37.1 months , HR 1.03 [ 95 % CI 0.79-1 .35 ] , p = 0.82 ) .