Table 1 Clinical characteristics of patients with different EGFR mutation statuses in the training and test sets

N

161

243

41

71

Age (years)

64.8 (9.1)

63.7 (9.2)

0.210

64.2 (8.8)

63.2 (9.4)

0.556

Gender

 < 0.001

0.018

Female

51 (31.7%)

162 (66.7%)

13 (31.7%)

39 (54.9%)

Male

110 (68.3%)

81 (33.3%)

28 (68.3%)

32 (45.1%)

Smoking history

87 (54.0%)

54 (22.2%)

 < 0.001

18 (43.9%)

16 (22.5%)

0.018

Type of nodules

 < 0.001

0.030

Solid

128 (79.5%)

147 (60.5%)

32 (78.1%)

41 (57.8%)

Subsolid

33 (20.5%)

96 (39.5%)

9 (22.0%)

30 (42.3%)

Location of nodules

0.645

0.662

Upper right

47 (29.2%)

81 (33.3%)

10 (24.4%)

21 (29.6%)

Middle right

6 (3.7%)

14 (5.8%)

4 (9.8%)

8 (11.3%)

Lower right

34 (21.1%)

50 (20.6%)

12 (29.3%)

14 (19.7%)

Upper left

44 (27.3%)

63 (25.9%)

9 (22.0%)

21 (29.6%)

Lower left

30 (18.6%)

35 (14.4%)

6 (14.6%)

7 (9.9%)

Tumor long axis (mm)

32.1

(20.7–47.2)

25.6

(20.3–37.6)

0.002

40.7 (29.5–49.5)

29.4 (23.5–38.3)

0.006

Tumor short axis (mm)

23.2 (14.6–33.2)

19.0 (14.3–27.7)

0.015

29.6 (24.1–33.4)

22.2 (16.0–28.4)

0.006

Clinical stage

0.005

0.228

I

52 (32.3%)

125 (51.4%)

8 (19.5%)

25 (35.2%)

II

12 (7.5%)

3 (1.2%)

4 (9.8%)

5 (7.0%)

III

33 (20.5%)

35 (14.4%)

8 (19.5%)

9 (12.7%)

IV

64 (39.8%)

80 (32.9%)

21 (51.2%)

32 (45.1%)

CEA (ng/ml)

5.24

(2.61–15.61)

3.23

(1.60–12.25)

0.016

5.08

(2.42–13.39)

5.28

(2.09–18.68)

0.880

SUVmax

13.03

(6.27–18.21)

10.14

(3.44–17.51)

0.005

15.60

(8.51–20.67)

13.55

(4.85–17.97)

0.114