Table 2 Multivariable Cox analysis of disease-free survival in validation cohort 1

Age (continuous)

1.00 (0.98–1.01)

0.417

Sex (male vs. female)

1.10 (0.82–1.44)

0.551

Smoke (yes vs. no)

1.21 (0.86–1.70)

0.275

Location (left vs. right)

0.92 (0.70–1.23)

0.586

Surgery (lobectomy vs. sublobar resection)

1.61 (0.99–2.62)

0.054

0.76 (0.46–1.25)

0.279

0.75 (0.46–1.23)

0.258

EGFR mutation (positive vs. negative)

0.81 (0.61–1.08)

0.151

KRAS mutation (positive vs. negative)

1.31 (0.81–2.13)

0.277

VPI (present vs. absent)

2.17 (1.63–2.90)

<0.001

1.12 (0.82–1.53)

0.466

1.09 (0.80–1.49)

0.575

STAS (present vs. absent)

2.09 (1.58–2.76)

<0.001

0.99 (0.72–1.34)

0.922

1.01 (0.74–1.37)

0.965

LVI (present vs. absent)

1.96 (1.40–2.75)

<0.001

0.96 (0.67–1.37)

0.825

0.98 (0.69–1.40)

0.918

 II vs. I

14.13 (3.41–58.65)

<0.001

13.17 (3.16–54.96)

<0.001

13.54 (3.24–56.52)

<0.001

 III vs. I

37.77 (9.36–152.50)

<0.001

26.99 (6.50–112.13)

<0.001

25.69 (6.19–106.63)

<0.001

 II vs. I

2.25 (1.42–3.57)

0.001

1.59 (0.98–2.57)

0.061

1.67 (1.03–2.71)

0.037

 III vs. I

5.83 (4.31–7.90)

<0.001

4.04 (2.83–5.76)

<0.001

4.22 (2.95–6.05)

<0.001

Adjuvant chemotherapy (yes vs. no)

1.91 (1.45–2.52)

<0.001

0.82 (0.60-1.13)

0.219

0.77 (0.56–1.07)

0.117

WSI-based score (high risk vs. low risk)

1.95 (1.46–2.62)

<0.001

1.82 (1.35–2.44)

<0.001