Table 1 Baseline characteristics of the patients

Age at diagnosis, years

 Mean ± S.D^†

58.8 ± 7.1

 Median (range)

58 (44–70)

Sex, n (%)

 Male

38 (80.9)

 Female

9 (19.1)

History of smoking, n (%)

 Former or current

33 (70.2)

 Never

14 (29.8)

Site of primary tumor, n (%)

 Upper thoracic

2 (4.3%)

 Middle thoracic

26 (55.3)

 Lower thoracic

19 (40.4)

Histologic grade, n (%)

 Well-differentiated

5 (10.7)

 Moderately differentiated

30 (63.8)

 Poorly differentiated

12 (25.5)

Clinical T stage, n (%)

 T1

0 (0)

 T2

12 (25.5)

 T3

35 (74.5)

 T4

0 (0)

Clinical N state, n (%)

 N0

3 (6.4)

 N1

17 (36.2)

 N2

27 (57.4)

Tumor stage^‡, n (%)

 II

11 (23.4)

 III

36 (76.6)

ECOG score, n (%)

 0

41 (87.2)

 1

6 (12.8)