The FA values were significantly higher in patients with glioblastomas than in those with astrocytomas (IDH-wt vs. IDH-mut groups: 0.20 ± 0.04 vs. 0.16 ± 0.03; p < 0.0001; Figure 1A); the cut-off value, AUC, sensitivity, and specificity were 0.18, 0.78, 67%, and 82%, respectively (Figure 1B). The gene discussed is IDH2; the disease is astrocytoma (excluding glioblastoma).