Additionally, univariate Cox regression model analysis revealed that poor survival was significantly associated with AJCC (hazard ratio (HR): 3.790, 95% confidence interval (95% CI): 1.889–7.605; P<0.001), tumor differentiation (HR: 2.434, 95% CI: 1.345–4.405; P=0.003), tumor size (HR: 2.462, 95% CI: 1.147–5.284; P=0.021), nodal metastasis (HR: 3.135, 95% CI: 1.588–6.188; P=0.001) and CDK5 expression (HR: 3.457, 95% CI: 1.563–7.645; P=0.002). This evidence concerns the gene CDK5 and neoplasm.