Table 2. Multivariate analyses of PFS and OS.

Subgroup	PFS					OS
	HR (log-rank)	Lower limit	Upper limit	P value		HR (log-rank)	Lower limit	Upper limit	P value
ECOG (0–1 vs. ≥2)	0.457	0.179	1.166	0.101		0.117	0.040	0.345	<0.0001*
Pathology (adenocarcinoma vs. squamous)	0.343	0.172	0.686	0.002*		0.450	0.165	1.229	0.119
Liver metastasis (yes vs. no)	1.251	0.682	2.293	0.469		1.236	0.545	2.806	0.612
Bone therapy (yes vs. no)	0.440	0.265	0.729	0.001*		0.614	0.305	1.239	0.173
Treatment line (1 vs. ≥2)	0.620	0.396	0.970	0.036*		0.372	0.190	0.728	0.004*

*, P<0.05. PFS, progression-free survival; OS, overall survival; ECOG PS, Eastern Cooperation Oncology Group performance status; HR, hazard ratio.