Table 3. Details of multivariate analysis for progression-free survival.

Variable	Hazard ratio	p value on Cox regression analysis
Elderly	0.635 (0.387–1.040)	0.071
Gender	1.517 (1.032–2.229)	0.034
ECOG PS	1.252 (0.556–2.818)	0.587
Smoking status	1.140 (0.717–1.814)	0.580
Liver metastasis	1.499 (1.012–2.220)	0.043
Brain metastasis	1.357 (0.836–2.201)	0.216
EGFR mutation type	0.904 (0.620–1.317)	0.599