IDH2 and astrocytoma (excluding glioblastoma): In IDH-mutant astrocytomas, NF1 alterations occurred in 17 of 27 cases, while LZTR1 mutations (nonsense, frameshift, splice site, or missense) were also observed, consistent with loss of its role in targeting RAS proteins, among others, for ubiquitin-mediated degradation [62].