IDH1 and astrocytoma (excluding glioblastoma): We describe the case of a 21-year-old female New Zealander of European descent with O6-methylguanine-DNA methyltransferase promoter-methylated, IDH1-R132H-mutant astrocytoma (World Health Organization 2021 central nervous system grade 4) containing a primitive neuroectodermal tumor-like component, which exhibited diffuse skeletal and leptomeningeal metastases.