IDH1 and central nervous system cancer: PFS was significantly longer in patients with grade II gliomas harboring IDH1-R132H than in patients with IDH1 wild-type tumors (Median PFS of IDH1-R132H = 893 days, Median PFS of IDH1-wt = 580 days, p = 0.0009, log-rank test; Figure 4A).