PIK3CA and central nervous system cancer: Other previously reported midline glioma biomarkers were observed at various frequencies, including TP53 (35/112,31%), TERT promoter mutations (27/112, 24%), PTEN (23/112, 21%), PDGFRA (18/112, 16%; recurrent point mutations at E227K, N659K, A810T, D842V/Y, and CN gain), ATRX (16/112, 14%), PIK3CA (16/112, 14%; at R81Q, R93W, R108H, E542K, E545K, H1047R, H1065Y), BRAF (14/112, 12%; primarily at V600E), NF1 (14/112, 12%; mainly frameshift and nonsense mutations) and FGFR1 (9/112, 8%; at G348E, N546K, V561L/M, and K656E) (Figure 1A, Figure S1, and Table S2).