Table 3

Overall survival of patients with stage I lung adenocarcinoma in relation to molecular and clinicopathological characteristics

Variable	Subset	Incidence^a (%)	P
Variable	Subset	Incidence^a (%)				Univariate^b	Multivariate^c
Gender	Male	21/64 (33)	0.0150	0.077
	Female	5/46 (11)		(Risk ratio 2.440; 95% CI, 0.907–6.565)
Age	<60	5/41 (12)	0.0670	0.125 (<60 vs. 60–69)
	60–69	10/39 (26)		(Risk ratio 2.375; 95% CI, 0.786–7.175)
	>69	11/30 (37)		0.032 (<60 vs. ≥69)
				(Risk ratio 3.190; 95% CI, 1.084–9.388)
Smoking history	Smoker	18/62 (29)	0.1617	NS^d
	Nonsmoker	8/48 (17)
T stage	T1	13/75 (17)	0.0600	0.104
	T2	13/35 (37)		(Risk ratio 1.934; 95% CI, 0.873–4.292)
Differentiation	Poorly	4/17 (24)	0.9664	NS
	Moderately	9/37 (24)
	Well	13/56 (23)
Vascular invasion	+	11/31 (35)	0.1190	NS
	−	15/79 (19)
Lymphatic permeation	+	7/22 (32)	0.1922	NS
	−	19/88 (22)
Pleural involvement	+	8/26 (31)	0.4143	NS
	−	18/84 (21)
RASSF1A methylation	+	13/35 (37)	0.0368	0.032
	−	13/75 (17)		(Risk ratio 2.357; 95% CI, 1.075–5.169)
p53 mutation	+	12/37 (32)	0.1630	NS
	−	14/73 (19)
K-ras mutation	+	1/13 (8)	0.1818	NS
	−	25/97 (26)
AI at 3p21.3	+	11/42 (26)	0.7243	NS
	−	12/61 (20)

^a Incidence is expressed by the number of patients who died of lung cancer per the number of patients in total.
^b Log-rank test.
^c Stepwise Cox proportional hazards regression model.
^d NS, not selected in stepwise Cox proportional regression model.