Astrocytomas (IDH-mut) were observed in 100% (n = 6/6) of the cases with 0 points and 83.0% (n = 44/53) of the cases with 0–1 points; conversely, glioblastomas (IDH-wt) were observed in 62.1% (n = 18/29) of the cases with 2–3 points and 80.0% (n = 8/10) of the cases with 3 points. Here, IDH1 is linked to astrocytoma (excluding glioblastoma).