Table 3. Cox multivariate analyses of prognostic factors for overall survival.

Variables	Hazards ratio	95% CI	P value
Training cohort
Tumor size, cm (≤4* v >4)	1.134	0.783–1.643	0.506
Differentiation (well v moderate v poor)	1.103	0.816–1.490	0.525
pT classification (T1 v T2 v T3)	1.113	0.726–1.706	0.622
pN classification (N0 v N1 v N2 v N3)	1.759	1.260–2.455	0.001
Stage (I v II v III)	1.505	0.771–2.937	0.231
Vascular invasion (absent v present)	1.622	1.096–2.401	0.016
Validation cohort
Tumor size, cm (≤4 v >4)	1.104	0.747–1.633	0.619
Differentiation (well v moderate v poor)	1.181	0.853–1.634	0.317
pT classification (T1 v T2 v T3)	1.421	0.900–2.241	0.131
pN classification (N0 v N1 v N2 v N3)	1.512	1.087–2.103	0.014
Stage (I v II v III)	0.924	0.513–1.663	0.791
Vascular invasion (absent v present)	1.655	1.100–2.489	0.016

*Median size; CI, confidence interval.