Table 4– Factors affecting overall survival of stage IV lung adenocarcinoma patients with malignant pleural effusions (MPEs)

	Patients	Overall survival months	Univariate analysis	Multivariate analysis
	Patients	Overall survival months	p-value	HR (95% CI)	p-value
Sex
Female	244	15.6
Male	204	15.5	0.440	1.00 (0.77–1.30)	0.974
Age
<65 years	203	18.4
≥65 years	245	13.2	0.004	1.13 (0.92–1.40)	0.243
Smoking
Never-smokers	329	16.5
Smokers	119	12.8	0.009	1.08 (0.81–1.46)	0.597
ECOG PS
0–1	354	17.4
2–4	94	6.6	<0.001	2.22 (1.71–2.87)	<0.001
Stage IV
M1a	179	20.9
M1b	269	13.8	<0.001	1.79 (1.43–2.24)	<0.001
MPE
Following disease progression	83	21.4
At initial diagnosis	365	14.3	0.001	1.65 (1.26–2.15)	<0.001
*EGFR*
Wild-type	152	10.9
Mutation	296	17.4	0.005	0.76 (0.61–0.95)	0.015
EGFR-TKI therapy
No	80	6.8
Yes	368	16.8	<0.001	0.51 (0.37–0.69)	<0.001

Data are presented as n, unless otherwise stated. HR: hazard ratio; 95% CI: 95% confidence interval; ECOG PS: Eastern Cooperative Oncology Group performance status; EGFR: epidermal growth factor receptor; EGFR: epidermal growth factor receptor gene; TKI: tyrosine kinase inhibitor.