Table 2 Univariate and multivariate analysis of OS

Gender

0.393 (0.283–0.546)

< 0.001

0.538 (0.352–0.821)

0.004

Age (year)

1.049 (1.033–1.066)

< 0.001

1.042 (1.025–1.058)

< 0.001

Tumor size (cm)

1.461 (1.288–1.657)

< 0.001

1.274 (1.075–1.510)

0.005

Smoking history

2.067 (1.558–2.742)

< 0.001

1.107 (0.764–1.603)

0.592

8th TNM stage

1.818 (1.364–2.425)

< 0.001

1.196 (0.762–1.878)

0.437

Visceral pleural invasion

1.281 (0.973–1.687)

0.077

1.180 (0.818–1.702)

0.377

 Squamous cell carcinoma

Ref

Ref

 Adenocarcinoma

0.629 (0.459–0.864)

0.004

1.061 (0.745–1.513)

0.742

 Others

0,946 (0.581–1.1542)

0.825

1.225 (0.734–2.043)

0.437

Differentiation degree

1.683 (1.341–2.112)

< 0.001

1.349 (1.063–1.711)

0.014

Vascular invasion

1.899 (1.119–3.222)

0.017

1.398 (0.805–2.429)

0.235

 0–2

Ref

 3–5

0.427 (0.244–0.783)

0.006

0.565 (0.302–1.056)

0.073

 6–8

0.629 (0.368–1.073)

0.089

0.745 (0.429–1.294)

0.296

 9–11

0.516 (0.292–0.913)

0.023

0.663 (0.367–1.198)

0.174

 12–14

0.648 (0.372–1.129)

0.126

0.887 (0.497–1.583)

0.686

 > 14

0.563 (0.342–0.929)

0.024

0.654 (0.388–1.102)

0.111

Adjuvant chemotherapy

0.925 (0.625–1.369)

0.695

Thoracotomy or VATS

0.864 (0.655–1.141)

0.304

 0–2

Ref

Ref

 3–5

0.702 (0.451–1.091)

0.116

0.631 (0.403–0.987)

0.044

 6–8

0.533 (0.336–0.844)

0.007

0.489 (0.307–0.779)

0.003

 9–11

0.630 (0.398–0.997)

0.049

0.599 (0.375–0.957)

0.032

 > 11

0.527 (0.329–1.845)

0.008

0.434 (0.269–0.701)

0.001