Table 5 Factors associated with progression-free survival (PFS) by univariate and multivariate Cox's proportional hazards regression analysis

Presence of COPD

0.304

0.112–0.827

0.020

0.321

0.111–0.930

0.036

Age(> 65 vs. ≤ 65)

1.801

0.790 -4.105

0.162

2.733

1.119–6.677

0.027

Sex(male vs. female)

0.770

0.227 -2.616

0.676

SI, pack-years (> 20 vs. ≤ 20)

0.847

0.357 -2.008

0.705

PCR

0.675

0.409–1.112

0.123

0.733

0.439–1.225

0.236

Histology(non-SCC vs. SCC)

1.143

0.388–3.371

0.809

0.981

0.302–3.190

0.974

ECOG PS score (1 vs. 0)

1.056

0.463 -2.412

0.896

cTNM Stage^a

2.448

0.907–6.603

0.077

2.606

0.905–7.508

0.076

Neoadjuvant cycle(> 2 vs. ≤ 2)

1.212

0.504–2.914

0.667

0.937

0.359–2.446

0.895

Adjuvant cycle(> 6vs. ≤ 6)

0.737

0.301–1.803

0.503