CDKN2A and glioblastoma: Although these tumors commonly have molecular profiles featuring EGFR (epidermal growth factor receptor) amplification, PTEN (phosphatase and tensin homolog) loss and homozygous CDKN2A deletion as well as TERT promoter mutations which are hallmarks of glioblastoma, they do not fulfill the diagnostic criteria of glioblastoma and have a better prognosis (Brat et al. 2015; Weller et al. 2015; Pekmezci et al. 2017; Ceccarelli et al. 2016).