Table 3. Univariate and multivariate analyses of prognostic factors and overall survival of patients in the study.

Variables	Categories	Univariate analysis		Multivariate analysis
		HR (95% CI)	P value	HR (95% CI)	P value
Training set, n=498
Age	≧60/<60years	1.263 (0.767-2.081)	0.358
Sex	male/female	1.177 (0.767-2.081)	0.465
Local invasion	T3-T4/T1-T2	3.798 (1.752-13.14)	0.013	2.206 (1.139-7.029)	0.027
Lymph node metastasis	N0/N1-N2	3.207 (2.026-5.075)	<0.0001	1.172 (0.672-2.044)	0.576
Distant metastasis	M0/M1	3.289 (3.397-7.235)	<0.0001	2.464 (1.363-4.453)	0.003
TNM stage	I-II/III-IV	4.348 (2.661-7.104)	<0.0001	2.151 (1.165-3.971)	0.014
Risk score(RS)	High/low	5.641 (3.441-9.245)	<0.0001	4.463 (2.687-7.413)	<0.0001
Testing set, n=100
Age	≧60/<60years	1.126 (0.972-1.305)	0.112
Sex	male/female	0.948 (0.864-1.041)	0.271
Local invasion	T3-T4/T1-T2	2.008 (1.129-3.571)	0.017	1.503 (0.8583-2.634)	0.153
Lymph node metastasis	N0/N1-N2	2.729 (1.655-4.501)	0.0001	2.928 (0.197-3.933)	0.478
Distant metastasis	M0/M1	2.383 (1.906-2.978)	<0.0001	2.951 (1.122-7.759)	0.028
TNM stage	I-II/III-IV	3.177 (1.995-5.061)	<0.0001	3.548 (1.037-12.13)	0.009
Risk score(RS)	High/low	2.542 (1.671-3.879)	<0.0001	2.206 (1.139-7.029)	0.004
Independent set, n=65
Age	≧60/<60years	1.247 (0.446-2.318)	0.612
Sex	male/female	1.642 (0.845–3.120)	0.385
Local invasion	T3-T4/T1-T2	1.677 (0.394-7.141)	0.483
Lymph node metastasis	N0/N1-N2	2.969(1.123-7.845)	0.028	2.281 (1.189-3.784)	0.021
Distant metastasis	M0/M1	3.289 (3.397-7.235)	<0.0001	2.367 (1.394-4.019)	0.001
TNM stage	I-II/III-IV	5.008 (2.242-11.410)	<0.0001	2.138 (1.047-3.841)	0.025
Risk score(RS)	High/low	5.025 (2.259–11.643)	0.0002	4.247 (2.132-8.463)	<0.0001

HR, hazard ratio; CI, confidential interval.