Table 2. Clinical and genetic features of WHO grade II gliomas (n = 417).
| Characteristics | IDH1 mutation (%) | IDH1 wide-type (%) | P-value |
|---|---|---|---|
| No. of cases | 309(74) | 108(26) | |
| Gender (F/M) | 128(41)/181 | 34(31)/73 | 0.078 |
| Age (<40 / ≥40yrs) | 187/125 | 52/55 | 0.041 |
| Histopathology | |||
| Astrocytomas | 139(45) | 49(45) | 0.945 |
| Oligodendrogliomas | 36(12) | 11(10) | 0.678 |
| Oligoastrocytomas | 134(43) | 48(44) | 0.846 |
| Tumor location | |||
| Frontal lobe | 224(72) | 64(59) | 0.010 |
| Temporal lobe | 105(34) | 45(42) | 0.152 |
| Parietal lobe | 23(7) | 8(7) | 0.288 |
| Insula | 63(20) | 23(21) | 0.841 |
| Occipital lobe | 6(2) | 6(6) | 0.110 |
| Others | 20(6) | 12(11) | 0.119 |
| Extent of resection | |||
| GTR (%) | 109(38)/176 | 44(45)/54 | 0.246 |
| Molecular biomarkers | |||
| MGMT promoter methylation (high/low) | 42(65)/23 | 6(33)/12 | 0.017 |
| 1p/19q loss (Yes/No) | 89(30)/208 | 32(31)/71 | 0.834 |
| Mutant TP53 (Yes/No) | 81(36)/145 | 7(9)/73 | <0.001 |