In total, we collected 68 tumor biopsies from 21 patients and the 2016 WHO diagnoses were updated according to the 2021 WHO classification system, which resulted in 10 IDH-mutant gliomas (four astrocytomas, CNS WHO grade 2–4 and six 1p/19q codeleted oligodendrogliomas, CNS WHO grade 2–3), two glioblastomas IDH-wildtype, CNS WHO grade 4 and nine meningiomas, CNS WHO grade 2 (Supplementary Table 2). This evidence concerns the gene IDH1 and oligodendroglioma.