Clinical factors listed in Table 2 were firstly tested for their association with PFS using the Cox proportional hazards model; significant prognostic factors for PFS on univariate analysis were histological grade (HR, 1.96; 95% CI, 1.09 to 3.57; P = 0.026), recurrent status (HR, 1.90; 95% CI, 1.3 to 2.77; P = .001), tumor resection grade (HR, 4.01; 95% CI, 2.19 to 7.34; P = 0.000), Ki-67 labeling index (HR, 2.01; 95% CI, 1.10 to 3.65; P = 0.022), preoperative KPS (HR, 0.42; 95% CI, 0.23 to 0.76; P = 0.004) and tumor location (HR, 0.48; 95% CI, 0.26 to 0.90; P = 0.021) (Figure 1 and Table 2). The gene discussed is MKI67; the disease is neoplasm.