Table 1.
Baseline of the Clinical-Pathological Characteristics Between of Two Cohorts
| Characteristics | Training | % | Validation | % | P-value | |
|---|---|---|---|---|---|---|
| Number of patients | 1010 | 49.3 | 1037 | 50.7 | ||
| Age | 50.8±10.8 | 50.0±10.2 |
0.082 | |||
| Tumor locationa | 0.069 | |||||
| UOQ | 469 | 53.0 | 438 | 49.8 | ||
| LOQ | 122 | 13.8 | 138 | 15.7 | ||
| UIQ | 169 | 19.1 | 179 | 20.4 | ||
| LIQ | 61 | 6.9 | 51 | 5.8 | ||
| Central | 46 | 5.2 | 47 | 5.3 | ||
| Others* | 18 | 2.0 | 26 | 3.0 | ||
| Clinical tumor sizeb | 0.186 | |||||
| ≤2.0 | 639 | 63.3 | 624 | 60.2 | ||
| >2.0 | 371 | 36.7 | 413 | 39.8 | ||
| Pathological type | 0.102 | |||||
| IDC | 864 | 85.5 | 902 | 87.0 | ||
| ILC | 24 | 2.4 | 24 | 2.3 | ||
| Others** | 122 | 12.1 | 111 | 10.7 | ||
| Histologic grade | 0.078 | |||||
| I | 62 | 6.1 | 88 | 8.5 | ||
| II | 521 | 51.6 | 572 | 55.2 | ||
| III | 319 | 31.6 | 299 | 28.8 | ||
| N.A.*** | 108 | 10.7 | 78 | 7.5 | ||
| ER c | 0.099 | |||||
| Positive | 788 | 78 | 777 | 74.9 | ||
| Negative | 222 | 22 | 260 | 25.1 | ||
| PRc | 0.915 | |||||
| Positive | 661 | 65.4 | 681 | 65.7 | ||
| Negative | 349 | 34.6 | 356 | 34.3 | ||
| Ki-67 | 0.234 | |||||
| <15% | 244 | 24.2 | 298 | 28.7 | ||
| 15-30% | 415 | 41.1 | 356 | 34.3 | ||
| >30% | 351 | 34.8 | 383 | 36.9 | ||
| HER-2 receptor statusd | 0.213 | |||||
| Positive | 222 | 22 | 252 | 24.3 | ||
| Negative | 788 | 78 | 785 | 75.7 | ||
| Multifocality | 0.301 | |||||
| Unifocal | 956 | 94.7 | 967 | 93.3 | ||
| Multifocal | 50 | 5.0 | 67 | 6.5 | ||
| Multicentric | 4 | 0.4 | 3 | 0.3 | ||
| Lymph node status | 0.053 | |||||
| Negative | 769 | 76.1 | 893 | 86.1 | ||
| Positive | 241 | 23.9 | 144 | 13.9 | ||
| Molecular subtype | 0.110 | |||||
| Luminal | 788 | 78.0 | 777 | 74.9 | ||
| HER-2+ | 91 | 9.0 | 122 | 11.8 | ||
| TN | 131 | 13 | 138 | 13.3 |
Notes: aIn the case of multifocal tumors or unifocal tumors involving more than one quadrant, the tumor locations are classified in the following priority order: upper outer quadrant (UOQ), central, lower outer quadrant (LOQ), lower inner lower quadrant (LIQ), and upper inner quadrant (UIQ). For example, the inner and central regions are divided into the central quadrant. The central and outer quadrants involved are classified as outer. If all quadrants are included, the tumor is classified as the outer upper quadrant. Others (other) are occult breast cancer or tumors that cannot be found by manual examination. bClinical tumor size assessment by preoperative ultrasound. cThe positivity of estrogen and progesterone receptors was defined as at least 10% or more immunostained cells. dPositivity for HER-2 was defined as HER-2 gene amplification using the fluorescence in situ hybridization by the HER-2/neu probe kit, or scoring >3 using the immunohistochemistry method. *Others: occult breast cancer or tumors that cannot be found by manual examination. **Others: mucinous carcinoma, infiltrating carcinoma with medullary characteristics, squamous cell carcinoma, papillary carcinoma, infiltrating micropapillary carcinoma, sieve carcinoma, medullary carcinoma, tubular carcinoma, etc. ***Some specific types of cancer are not histologically graded. N.A, not available.