Table 2 Clinical characteristics and CT parameters in the training cohort and validation cohort

Baseline characteristics of the patients

Age(mean [SD], year)

66 ± 11

66.57 ± 11

64 ± 10

0.322

BMI (median [IQR], kg/m²)

23.35 (21.63–25.48)

23.44 (21.50–25.59)

23.18 (21.97–25.20)

0.847

Gender, n (%)

0.772

 Female

74 (39.78)

53 (40.46)

21 (38.18)

 Male

112 (60.22)

78 (59.54)

34 (61.82)

ASA, n (%)

0.726

 1

22 (11.83)

17 (12.98)

5 (9.09)

 2

114 (61.29)

80 (61.07)

34 (61.82)

 3

50 (26.88)

34 (25.95)

16 (29.09)

Hypertension, n (%)

0.863

 No

110 (59.14)

78 (59.54)

32 (58.18)

 Yes

76 (40.86)

53 (40.46)

23 (41.82)

Diabetes, n (%)

0.157

 No

165 (88.71)

119 (90.84)

46 (83.64)

 Yes

21 (11.29)

12 (9.16)

9 (16.36)

CT measurement parameters

SAT area(mean [SD], cm2)

127.55 ± 55.04

128.57 ± 59.40

125.13 ± 43.29

0.699

SAT Radiodensity(mean [SD], U)

-97.34 ± 9.03

-96.95 ± 8.73

-98.27 ± 7.10

0.367

VAT Radiodensity( mean [SD], U)

-94.08 ± 8.36

-94.18 ± 8.57

-93.83 ± 7.89

0.793

Distance between tumor and the dentate line, n (%)

0.053

 < 10cm

98 (52.69)

63 (48.09)

35 (63.64)

 ≥ 10 cm

88 (47.31)

68 (51.91)

20 (36.36)

Tumor diameter, n (%)

0.355

 ≤ 3 cm

85 (45.7)

57 (43.51)

28 (50.91)

 >3 cm

101 (54.3)

74 (56.49)

27 (49.09)

Pathological stage

Pathological T stage, n (%)

0.982

 T1

132 (70.97)

93 (70.99)

39 (70.91)

 T2

43 (23.12)

30 (22.90)

13 (23.64)

 T3

11 (5.91)

8 (6.11)

3 (5.45)

Pathological N stage, n (%)

0.195

 N0

112 (60.22)

75 (57.25)

37 (67.27)

 N1

39 (20.97)

27 (20.61)

12 (21.82)

 N2

35 (18.82)

29 (22.14)

6 (10.91)

Nerve invasion, n (%)

0.396

 No

146 (78.49)

105 (80.15)

41 (74.55)

 Yes

40 (21.51)

26 (19.85)

14 (25.45)

Vascular tumor emboli, n (%)

0.661

 No

152 (81.72)

106 (80.92)

46 (83.64)

 Yes

34 (18.28)

25 (19.08)

9 (16.36)

Blood Laboratory indicators

Preoperative total cholesterol (median [IQR])

4.63 (4.24–5.20)

4.59 (4.17–5.11)

4.65 (4.30–5.23)

0.381

Preoperative triglyceride(median [IQR])

1.18 (0.95–1.45)

1.23 (1.01–1.46)

1.09 (0.71–1.38)

0.021

Preoperative C reactive protein count(median [IQR])

5.20 (4.70–5.70)

5.10 (4.70–5.70)

5.50 (4.90–5.70)

0.058

Preoperative serum albumin, n (%)

0.854

 <35 g/L

39 (20.97)

27 (20.61)

12 (21.82)

 ≥ 35 g/L

147 (79.03)

104 (79.39)

43 (78.18)

Preoperative hemoglobin (mean [SD])

129.78 ± 17.67

128.90 ± 16.78

131.87 ± 19.63

0.296

SIG, n (%)

0.22

 0

121 (65.05)

87 (66.41)

34 (61.82)

 1

46 (24.73)

31 (23.66)

15 (27.27)

 2

13 (6.99)

7 (5.34)

6 (10.91)

 3

6 (3.23)

6 (4.58)

0 (0.00)