Table 2. Multivariate analysis by Cox for OS.

Variables	β	SE (β)	Wald χ2	P	RR	95%CI for RR
N stage	0.343	0.099	12.038	0.001	1.409	(1.161, 1.711)
CEA	0.695	0.178	15.260	<0.0001	2.003	(1.414, 2.838)
CYFRA21-1	0.532	0.184	8.391	0.004	1.702	(1.188, 2.439)