Table 1 Patients’ baseline characteristics

Age(years) ^a

64(56–69)

0.346

 < 64

72 (49.3)

57 (47.5)

15 (57.7)

 ≥ 64

74 (50.7)

63 (52.5)

11 (42.3)

Gender ^b

 Male

111 (76.0)

93 (77.5)

18 (69.2)

0.371

 Female

35 (24.0)

27 (22.5)

8 (30.8)

Histology ^b

 Non- Squamous

101 (69.2)

82 (68.3)

19 (73.1)

0.635

 Squamous

45 (30.8)

38 (31.7)

7 (26.9)

Stage ^b

 IIIB

27 (18.5)

25 (20.8)

2 (7.7)

0.118

 IV

119 (81.5)

95 (79.2)

24 (92.3)

Differentiation ^b

 Moderate

13 (8.9)

9 (7.5)

4 (15.4)

0.641

 Medium-Low

18 (12.3)

15 (12.5)

3 (11.5)

 Low

34 (23.3)

28 (23.3)

6 (23.1)

 NA

81 (55.5)

68 (56.7)

13 (50.0)

ECOG PS ^b

 0

23 (15.8)

18 (15.0)

5 (19.2)

0.185

 1

108 (74.0)

92 (76.7)

16 (61.5)

 2

15 (10.3)

10 (8.3)

5 (19.2)

Smoking history ^b

 Never

62 (42.5)

48 (40.0)

14 (53.8)

0.195

 Now/Ever

84 (57.5)

72 (60.0)

12 (46.2)

Distant metastases ^b

 No

27 (18.5)

25 (20.8)

2 (7.7)

0.118

 Yes

119 (81.5)

95 (79.2)

24 (92.3)

Driver mutations ^b

 No

113 (77.4)

96 (80.0)

17 (65.4)

0.106

 Yes

33 (22.6)

24 (20.0)

9 (34.6)

PD-1 inhibitor type ^b

 Pembrolizumab

47 (32.2)

43 (35.8)

4 (15.4)

0.320

 Toripalimab

18 (12.3)

13 (10.8)

5 (19.2)

 Camrelizumab

31 (21.2)

24 (20.0)

7 (26.9)

 Sintilimab

44 (30.1)

35 (29.2)

9 (34.6)

 Tislelizumab

6 (4.1)

5 (4.2)

1 (3.8)

Combination regimen ^b

 Monotherapy

25 (17.1)

19 (15.8)

6 (23.1)

0.787

 Chemotherapy

89 (61.0)

75 (62.5)

14 (53.8)

 Anti-angiogenic therapy

28 (19.2)

23 (19.2)

5 (19.2)

 Both

4 (2.7)

3 (2.5)

1 (3.8)

Drug regiment ^b

 1st line

62 (42.5)

53 (44.2)

9 (34.6)

0.372

 ≥ 2nd line

84 (57.5)

67 (55.8)

17 (65.4)

Radiotherapy ^b

 No

69 (47.3)

53 (44.2)

16 (61.5)

0.108

 Yes

77 (52.7)

67 (55.8)

10 (38.5)