Table 1. Cox proportional hazards model analysis of prognostic factors.

Variables	Univariate analysis				Multivariate analysis
	HR	95% CI	P value		HR	95% CI	P value
Six-gene risk score	1.453	1.314–1.605	2.40E–13*		1.424	1.276–1.589	2.61E−10*
Age (<60 vs. ≥60)	1.033	1.017–1.049	3.69E–05*		1.032	1.015–1.049	0.0001*
TNM stage (III + IV vs. I + II)	2.123	1.653–2.727	3.71E–09*		1.700	0.951–3.040	0.0733*
T (tumor)	1.555	1.235–1.956	0.0001*		1.030	0.735–1.441	0.862
N (lymph node)	1.707	1.396–2.088	1.84E–07*		1.174	0.847–1.628	0.334
M (metastasis)	5.821	3.104–10.914	3.96E–08*		1.116	0.451–2.760	0.810

*, P value <0.05 was considered statistically significant.