Table 2.

Results of Cox regression analyses

Variables	Multivariable Cox regression analysis for PFS and OS
	PFS			OS
	HR	95% CI	P	HR	95% CI	P
Gender (male vs. female)	1.87	0.39–4.37	0.37	2.58	1.78–3.55	0.76
Age (< 65 vs. ≥ 65)	0.89	0.80–0.99	0.45	0.99	0.84–1.20	0.98
ECOG score (0–1 vs. 2)	0.91	0.31–2.65	0.86	0.39	0.11–1.36	0.14
Histology (adenocarcinoma vs. others)	2.25	0.76–6.70	0.15	0.94	0.27–3.2	0.92
T stage (T1 vs. T2/T3)	1.59	0.67–3.76	0.29	2.32	0.85–6.36	0.10
Nodal status (N2/N3 vs. N0/N1)	3.57	1.89–6.73	< 0.01	3.36	1.51–7.45	< 0.01
Metastasis location (lung vs. other sites)	2.54	0.64–4.58	0.53	1.65	0.67–3.47	0.34