For WHO grade and IDH-1 expression status significantly influenced the prognosis of the glioma patients, (1) the frequency of different recurrence patterns between WHO II/III and WHO IV patients was compared, which showed no significant difference (χ2 = 8.221, p=0.065, shown in Table 4); (2) the frequency of different recurrence patterns between IDH (+) and IDH(-) patients was compared, which showed no significant difference either(χ2 = 4.557, p=0.317, table not shown). This evidence concerns the gene IDH1 and central nervous system cancer.