Table 1 Characteristics of the training and validation cohorts

Age

55.84 ± 10.74

55.54 ± 11.66

0.822

Cortical thickness

0.670

 < 3

149(61.3%)

67(64.4%)

 ≥ 3

94(38.7%)

37(35.6%)

Longitudinal to transverse ratio

0.969

 ≥ 2

145 (59.7%)

63(60.6%)

 < 2

98 (40.3%)

41(39.4%)

Absence of hilum

0.913

 no

191 (78.6%)

83(79.8%)

 yes

52 (21.4%)

21(20.2%)

Location

0.867

 UIQ

39 (16.0%)

15 (14.4%)

 LIQ

16 (6.6%)

7 (6.7%)

 LOQ

47 (19.3%)

17(16.3%)

 UOQ

141 (58.0%)

65 (62.5%)

Orientation

0.751

 Parallel

174 (71.6%)

72 (69.2%)

 Non-parallel

69(28.4%)

32 (30.8%)

Shape

1

 Regular

27 (11.1%)

12 (11.5%)

 Irregular

216 (88.9%)

92 (88.5%)

Margin

0.316

 Circumscribed

41 (16.9%)

23 (22.1%)

 Non-circumscribed

202 (83.1%)

81 (77.9%)

Calcification

0.264

 No

104 (42.8%)

52 (50.0%)

 Yes

139 (57.2%)

52 (50.0%)

Attenuation

0.830

 No

159 (65.4%)

70 (67.3%)

 Yes

84 (34.6%)

34 (32.7%)

ER

0.800

 Negative

89 (36.6%)

34 (32.7%)

 1 + 

31(12.8%)

17(16.3%)

 2 + 

31(12.8%)

13(12.5%)

 3 + 

92(37.9%)

40 (38.5%)

PR

0.642

 Negative

109(44.9%)

43 (41.3%)

 1 + 

40(16.5%)

15(14.4%)

 2 + 

38(15.6%)

22(21.2%)

 3 + 

56(23.0%)

24 (23.1%)

Her-2

0.879

 Negative

195 (80.2%)

82 (78.8%)

 Positive

48 (19.8%)

22 (21.2%)

P53

0.485

 Negative

109 (44.9%)

42 (40.4%)

 Positive

113 (46.5%)

49 (47.1%)

 Unknow

21(8.6%)

13(12.5%)

Ki-67

0.217

 < 14

34 (14.0%)

19 (18.3%)

 ≥ 14

204 (84.0%)

85 (81.7%)

 Unknow

5(2.1%)

0(0.0%)

Tumor size

0.716

 T1

119 (49.0%)

48 (46.2%)

 T2

124 (51.0%)

56 (53.8%)

Histological grade

0.535

 I

18 (7.4%)

6 (5.8%)

 II

117 (48.1%)

57 (54.8%)

 III

104 (42.8%)

40 (38.4%)

 Unknow

4(1.6%)

1(1.0%)