CMRO<sub>2</sub> was decreased (P = .037) in low-grade glioma with a mutated IDH gene, and MTI was significantly increased in glioma grade III with IDH mutation (P = .013) when compared with the IDH wild-type counterparts.
In low-grade glioma (LGG) and glioblastoma cohorts of TCGA, significantly higher PD-L1 gene expression levels were evident in IDH-wt compared with IDH-mut samples (LGG: N = 516; P = 1.933e-11, GBM: N = 161; P < 0.009).
Tumor histology, size and IDH-mutation status are important predictors for prolonged overall survival in patients with LGG and may provide a reliable tool for standardizing future treatment strategies.
One such difference concerns mutations in the NADP(+)-dependent isocitrate dehydrogenase (IDH1 and IDH2) genes, which occur in >80% of cases of low grade glioma and secondary glioblastoma.
Subsequent studies have confirmed recurrent IDH1 and IDH2 mutations in up to 70% of low-grade glioma and secondary GBM, as well as in 10% of acute myeloid leukemia (AML) cases.