Table 2. Association of candidate gene methylation levels and clinicopathologic variables with overall survival in NSCLC cohort.

Variables	Univariate HR (95%CI)	Univariate P value	Multivariate HR (95%CI)	Multivariate P value
Age at surgery (years)	0.994 (0.937–1.054)	0.838	–	NA*
Gender (Male/Female)	1.304 (0.345–4.932)	0.696	–	NA*
Diagnosis (LUSC/LUAD)	1.036 (0.301–3.558)	0.956	–	NA*
Disease stage (III+IV/ I+II)	44.761 (5.721–350.202)	< 0.001	2.101 (0.083–53.323)	0.653
Smoking behavior (Yes/No)	2.154 (0.570–8.140)	0.258	–	NA*
Tumor location (Left lung/Right lung)	0.846 (0.245–2.914)	0.79	–	NA*
RECIST (PD/PR+SD)	108.952 (13.796–860.410)	< 0.001	57.750 (2.296–1452.838)	0.014
SFRP1 methylation	1.005 (1.000–1.011)	0.055	1.001 (0.996–1.007)	0.568
SFRP2 methylation	1.000 (0.998–1.002)	0.788	–	NA*
PRKCB methylation	1.006 (0.987–1.026)	0.536	–	NA*
WIF1 methylation	0.998 (0.989–1.006)	0.570	–	NA*

Bold value indicates statistical significance. * Not assessed due to an insignificant result in the univariate analysis (P > 0.1). Dichotomous data set the latter category as reference. PD: progressive disease; SD: stable disease; PR: partial response; HR: hazard ratio; CI: confidence interval; RECIST: Response Evaluation Criteria in Solid Tumors.