IDH1 and astrocytoma (excluding glioblastoma): In pediatric population, the incidence rate of IDH1/2 mutant astrocytoma was 0.09 per 100,000 population (Ostrom et al., 2022) with 9.1% tumors histologically low grades (WHO grade 1 and 2) and 9% high grades (WHO grade 3 and 4) (Yeo et al., 2023).