PIK3CA and astrocytoma (excluding glioblastoma): Astrocytoma had a 78% mutated frequency for ATRX in chromatin modifiers and other pathways and an 83% mutated frequency for TP53 in the TP53 pathway; oligodendroglioma displayed a 14% mutated frequency for PIK3CA in the RTK/RAS/PIK3/AKT pathway (Fig. 1D–E).