Table 1 Comparison of patients’ characteristics

Age (year-old)

71 (45–76)

Sex (male: female)

13:4

Tumor stage IV, n (%)

11 (64.7)

ECOG PS (0:1)

17:0

Smoking history, n (%)

9 (52.9)

Brinkman index

500.0 (0-1530)

History of lung disease, n (%)

0 (0)

Emphysema on CT scan, n (%)

4 (23.5)

Treatment, 1st line vs. later

15 (88.2)

CEA (ng/mL)

5.9 (1.3-109.1)

CA19-9 (U/mL)

200.4 (2.1–8543.0)

KL-6 (U/mL)

356.0 (187.0-1784.0)

SP-D (ng/mL)

198.6 (50.2-530.2)

ILD grade 1/2/3/4, n (%)

7 (41.1)/6 (35.3)/4 (23.5)/0 (0)