Table 1b Clinical characteristics of patients in the train cohort and internal validation cohort

Age, n (%)

χ²=0.225

0.635

<65

288 (50.35)

204 (51.00)

84 (48.84)

≥65

284 (49.65)

196 (49.00)

88 (51.16)

Gender, n (%)

χ²=0.139

0.709

Female

326 (56.99)

230 (57.50)

96 (55.81)

Male

246 (43.01)

170 (42.50)

76 (44.19)

Race, n (%)

χ²=3.907

0.142

Black

28 (4.9)

23 (5.75)

5 (2.91)

Others

78 (13.64)

49 (12.25)

29 (16.86)

White

466 (81.47)

328 (82.00)

138 (80.23)

T stage, n (%)

χ²=1.183

0.757

T1

146 (25.52)

101 (25.25)

45 (26.16)

T2

292 (51.05)

202 (50.50)

90 (52.33)

T3

98 (17.13)

69 (17.25)

29 (16.86)

T4

36 (6.29)

28 (7.00)

8 (4.65)

N stage, n (%)

χ²=1.537

0.215

N0

282 (49.3)

204 (51.00)

78 (45.35)

N1

290 (50.7)

196 (49.00)

94 (54.65)

Surgery, n (%)

χ²=1.664

0.197

No

498 (87.06)

353 (88.25)

145 (84.30)

Yes

74 (12.94)

47 (11.75)

27 (15.70)

Radiotherapy, n (%)

χ²=0.169

0.681

Yes

79 (13.81)

53 (13.25)

25 (14.53)

No

493 (86.19)

347 (86.75)

147 (85.47)

Chemotherapy, n (%)

χ²=0.777

0.378

No

178 (31.12)

120 (30.00)

58 (33.72)

Yes

394 (68.88)

280 (70.00)

114 (66.28)

Tumor Size, n (%)

χ²=0.012

0.911

>5 cm

443 (77.45)

311 (77.75)

133 (77.33)

≤5 cm

129 (22.55)

89 (22.25)

39 (22.67)

Bone metastasis, n (%)

χ²=0.265

0.606

No

447 (78.14)

317 (79.25)

133 (77.33)

Yes

125 (21.86)

83 (20.75)

39 (22.67)

Liver metastasis, n (%)

χ²=0.481

0.488

No

427 (74.65)

296 (74.00)

132 (76.74)

Yes

145 (25.35)

104 (26.00)

40 (23.26)

Lung metastasis, n (%)

χ²=0.154

0.694

No

422 (73.78)

297 (74.25)

125 (72.67)

Yes

150 (26.22)

103 (25.75)

47 (27.33)

Grade, n (%)

χ²=3.475

0.062

I + II

300 (52.45)

220 (55.00)

80 (46.51)

III + IV

272 (47.55)

180 (45.00)

92 (53.49)