CDKN2A and glioblastoma: Only one of the five cases was associated with lower OS (<9 months).5 In the Verhaak et al’s study, 1 out of 12 (8.3%) IDH-mutant GBM cases had co-occurrence of EGFR and PDGFRA amplifications with CDKN2A/B loss, with unclear prognostic significance6 (Table 1).