Table 5.

Univariate and multivariate analyses of clinical parameters of OS

	Univariate analysis			Multivariate analysis
Factors	HR	95% CI	P	HR	95% CI	P
Gender (female/male)	1.002	0.702–1.430	0.991
Age (< 65/≥ 65)	1.027	0.697–1.514	0.892
Smoking (never/ever)	0.872	0.580–1.310	0.509
ECOG (0–1/2–3)	0.604	0.374–0.977	0.040	0.598	0.364–0.980	0.042
Histology (adenocarcinoma/non‐adenocarcinoma)	0.962	0.568–1.629	0.884
EGFR mutation			0.278
19del/double mutation	1.273	0.460–3.523	0.642
L858R/double mutation	1.655	0.597–4.591	0.333
Other/double mutation	2.827	0.624–12.813	0.178
EGFR‐TKIs			0.097			0.029
Gefitinib/2‐TKIs	7.595	1.045–55.222	0.045	6.179	0.833–45.820	0.075
Erlotinib/2‐TKIs	6.225	0.849–45.635	0.072	4.024	0.538–30.118	0.175
Icotinib/2‐TKIs	4.221	0.566–36.114	0.155	2.882	0.345–24.111	0.329
Treatment line of EGFR‐TKIs (1/≥ 2)	1.185	0.824–1.704	0.359
Efficacy of EGFR‐TKIs			0.005			0.002
PR/PD	0.334	0.170–0.658	0.002	0.276	0.134–0.569	0.000
SD/PD	0.454	0.231–0.894	0.022	0.319	0.153–0.664	0.002
If re‐biopsied			<0.001			0.000
Re‐biopsy/no re‐biopsy	0.466	0.300–0.725	0.001	0.358	0.220–0.582	0.000
Liquid biopsy/no re‐biopsy	0.276	0.146–0.520	<0.001	0.279	0.145–0.535	0.000
TBR			0.450
T790M+ 3‐TKI+/T790M‐3‐TKI‐	0.707	0.407–1.229	0.219
T790M+ 3‐TKI‐/T790M‐3‐TKI‐	0.769	0.483–1.225	0.269
T790M‐ 3‐TKI+/T790M‐3‐TKI‐	0.673	0.246–1.842	0.441

Variables of P < 0.1 in univariate analysis were included into multivariate analysis. Treatment‐based result (TBR): patients were divided into four groups according to whether T790M was positive and third‐generation tyrosine kinase inhibitors (3‐TKIs) were used. 2‐TKIs, second‐generation TKIs; ECOG, Eastern Cooperative Oncology Group; OS, overall survival; PD, progressive disease; PR, partial response; SD, stable disease.