Table 6. Cox multiple regression for disease-free survival.

Factor	Hazard ratio	95% CIa	P-value
Growth pattern			0.007
Destructive	1
Papillary	1.665	0.966–2.871	0.067
Alveolar	2.023	1.264–3.235	0.003
N-status			<0.001
N0	1
N1	1.795	1.277–3.062	0.002
N2	2.717	1.930–5.060	<0.001
Type of operation
Lobectomy	1
Pneumonectomy	1.478	0.946–2.309	0.089

^a95% CI=95% confidence interval.