Table 2.

Overall survival stratified by clinical characteristics and univariate Cox proportional hazard analyses for patients

			Univariate analysis
Variables
	Mean survival (months)	95% CI	HR(95%CI)	P-value
Total	32.6	(31.2-33.9)
Age
<=78	33.9	(32.4-35.5)	Ref
>78	23.2	(20.5-25.8)	1.29(1.13-1.43)	<0.001
Gender
Female	21.8	(20.33-23.31)	Ref
Male	20.9	(19.35-22.52)	1.06(0.97-1.15)	0.202
Race
White	21.6	(20.37-22.89)	Ref
Black	17.3	(14.33-20.19)	1.13(0.97-1.31)	0.110
Other	23.3	(20.35-26.29)	0.92(0.8-1.05)	0.200
Marital status
Married	22.4	(20.96-23.86)	Ref
Single	20.0	(18.3-21.75)	1.06(0.97-1.16)	0.232
Laterality
Right	21.9	(20.43-23.3)	Ref
Left	22.3	(20.35-24.16)	1.07(0.98-1.17)	0.153
Bilateral	15.9	(9.83-22.04)	2.49(1.87-3.32)	<0.0001
Lobe
Upper	12.3	(8.01-16.57)	Ref
Middle	22.0	(20.41-23.69)	0.75(0.6-0.93)	0.011
Lower	29.7	(21.3-38.04)	0.92(0.83-1.02)	0.956
Main bronchus	24.9	(22.79-27.1)	2.19(1.62-2.95)	<0.001
Overlapping lesion of lung	20.0	(12-28)	1.33(0.93-1.89)	0.113
Grade
Well; I	30.6	(26.82-34.48)	Ref
Moderately; II	28.0	(25.5-30.5)	1.14(0.98-1.32)	0.098
Poorly; III	21.1	(17.94-24.32)	1.94(1.62-2.32)	<0.001
Undifferentiated; IV	21.0	(10.32-31.68)	1.47(0.9-2.41)	0.122
Node status
N0	29.4	(26.87-31.9)	Ref
N1-3	19.5	(18.16-20.89)	2.93(2.64-3.25)	<0.001
Metastasis status
M0	28.9	(27.05-30.77)	Ref
M1	13.8	(12.77-14.74)	3.62(3.29-3.97)	<0.001
Tumor size
<=38mm	41.7	(39.4-44.1)	Ref
>38mm	29.6	(27.2-31.9)	1.88(1.69-2.10)	<0.001
Surgery
Yes	35.8	(33.38-38.23)	Ref
No	14.3	(13.44-15.21)	4.77(4.33-5.26)	<0.001
Surgery type
Lobectomy/Bilobectomy	52.8	(49.9-55.6)	Ref
Partial resection	43.7	(32.1-55.4)	1.83(1.33-2.5)	<0.001
Pneumonectomy	39.4	(33.9-44.8)	1.8(1.49-2.17)	<0.001
Radiation
Yes	22.8	(21.3-24.22)	Ref
No	19.1	(17.57-20.71)	0.52(0.47-0.57)	<0.001
Chemotherapy
No	22.5	(20.77-24.14)	Ref
Yes	20.3	(18.95-21.66)	1.8(1.64-1.96)	<0.001

Abbreviation: 95% CI, 95% Confidence interval