In particular, amplification of PDGFR (platelet-derived growth factor receptor) genes, CDKN2A/CDKN2B homozygous deletion, and PI3K mutations were independently associated with worse prognosis in patients with anaplastic (WHO grade 3) astrocytomas (17). The gene discussed is CDKN2A; the disease is astrocytoma (excluding glioblastoma).