CDKN2A and glioblastoma: In glioblastoma, 82.8% of cases had cooccurrence of alterations between these 2 pathways, with alteration in CDKN2A/B impacting both the cell cycle and p53 pathways; 2.4% of glioblastoma had an alteration only in the cell cycle pathway and 4.8% only in the p53 pathway.