These included age (P = 0.035), presenting symptoms (P < 0.0001), pre-operative Karnofsky Performance Status (KPS) (P = 0.003), tumor location (P < 0.0001), extent of resection (P = 0.041), MGMT status (P = 0.008), and treatment after surgery (P < 0.0001) (Table 1). This evidence concerns the gene MGMT and neoplasm.