Table 1. Clinical characteristics of patients.
| Characteristics | Training set (n=1,355) [n (%)] |
Internal testing set (n=352) [n (%)] |
P | Pooled external testing set (n=95) [n (%)] |
P | Prospective testing set (n=101) [n (%)] |
P |
Age (year) ( ) |
58.04±11.68 | 52.30±11.74 | 0.754 | 49.32±10.23 | 0.014 | 51.97±12.18 | 0.805 |
Diameter (cm) ( ) |
2.30±1.15 | 2.29±1.28 | 0.965 | 2.71±1.29 | 0.006 | 2.60±1.41 | 0.048 |
| <1 | 120 (8.86) | 39 (11.08) | 2 (2.11) | 5 (4.95) | |||
| 1−2 | 539 (39.77) | 136 (38.63) | 31 (32.63) | 35 (34.65) | |||
| >2 | 696 (51.37) | 177 (50.29) | 62 (65.26) | 61 (60.40) | |||
| Benign lesions | 333 (24.58) | 99 (28.13) | − | 29 (30.53) | − | 29 (28.71) | − |
| Fibroadenoma | 159 (47.75) | 45 (45.45) | 14 (48.27) | 13 (44.83) | |||
| Adenosis | 79 (23.72) | 26 (26.27) | 13 (44.83) | 10 (34.48) | |||
| Intraductal papilloma | 34 (10.21) | 12 (12.12) | 2 (6.90) | 4 (13.79) | |||
| Inflammation | 8 (2.40) | 2 (2.02) | 0 (0) | 1 (3.45) | |||
| Fibrocystic disease | 10 (3.00) | 5 (5.05) | 0 (0) | 1 (3.45) | |||
| Phyllodes tumor | 19 (5.71) | 4 (4.04) | 0 (0) | 0 (0) | |||
| Unknow/other | 24 (7.21) | 5 (5.05) | 0 (0) | 0 (0) | |||
| Malignant lesions | 1,022 (75.42) | 253 (71.87) | − | 66 (69.47) | − | 72 (71.29) | − |
| Invasive ductal carcinoma |
897 (87.77) | 223 (88.14) | 46 (69.69) | 55 (76.39) | |||
| Ductal carcinoma in situ | 18 (1.76) | 6 (2.37) | 8 (12.12) | 7 (9.72) | |||
| Invasive lobular carcinoma |
24 (2.35) | 6 (2.37) | 1 (1.52) | 3 (4.17) | |||
| Papillary carcinoma | 10 (0.98) | 7 (2.77) | 0 (0) | 1 (1.39) | |||
| Mucinous adenocarcinoma |
14 (1.37) | 6 (2.37) | 0 (0) | 5 (6.94) | |||
| Unknow/other | 59 (5.77) | 5 (1.98) | 11 (16.67) | 1 (1.39) |

