Table 1.
Clinicopathological characteristics of breast cancer patients with ipsilateral supraclavicular lymph node metastasis in the training and validation cohorts.
| Characteristics | Training cohort, N (%) | Validation cohort, N (%) |
| Total | 231 (100.0) | 114 (100.0) |
| Age | ||
| ≤40 years | 43 (18.6) | 18 (15.8) |
| >40 years | 188 (81.4) | 96 (84.2) |
| Family history of cancer | ||
| Yes | 32 (13.9) | 14 (12.3) |
| No | 199 (86.1) | 100 (87.7) |
| Clinical T staging | ||
| T1+T2 | 173 (74.9) | 86 (75.4) |
| T3+T4 | 58 (25.1) | 28 (24.6) |
| ER status | ||
| Positive | 140 (60.6) | 62 (54.4) |
| Negative | 91 (39.4) | 52 (45.6) |
| PR status | ||
| Positive | 116 (50.2) | 60 (52.6) |
| Negative | 115 (49.8) | 54 (47.4) |
| HER2 status and Herceptin usage | ||
| HER2 negative | 125 (54.1) | 67 (58.8) |
| HER2 positive but not using Herceptin | 43 (18.6) | 21 (18.4) |
| HER2 positive and using Herceptin | 63 (27.3) | 26 (22.8) |
| Ki67 index | ||
| ≥30 | 201 (87.0) | 96 (84.2) |
| <30 | 30 (13.0) | 18 (15.8) |
| Palpability of ISLN before NAC | ||
| Yes | 50 (21.6) | 28 (24.6) |
| No | 181 (78.4) | 86 (75.4) |
| NAC regimens | ||
| Anthracycline plus taxane | 157 (68.0) | 84 (73.7) |
| Anthracycline based | 27 (11.7) | 11 (9.6) |
| Taxane based | 47 (20.3) | 19 (16.7) |
| Cycles of NAC | ||
| <5 | 54 (23.4) | 24 (21.1) |
| ≥5 | 177 (76.6) | 90 (78.9) |
| RECIST-based treatment response | ||
| CR+PR | 198 (85.7) | 97 (85.1) |
| SD+PD | 33 (14.3) | 17 (14.9) |
| Size of ISLN after NAC (mm) | ||
| <10 | 196 (84.8) | 87 (76.3) |
| ≥10 | 35 (15.2) | 27 (23.7) |
| Breast surgery strategies | ||
| Mastectomy | 226 (97.8) | 108 (94.7) |
| BCS+reconstruction | 5 (2.2) | 6 (5.3) |
| ISLND or not | ||
| Yes | 205 (88.7) | 95 (83.3) |
| No | 26 (11.3) | 19 (16.7) |
| Breast pCR | ||
| Yes | 77 (33.3) | 31 (27.2) |
| No | 154 (66.7) | 83 (72.8) |
| Axillary pCR | ||
| Yes | 77 (33.3) | 27 (23.7) |
| No | 154 (66.7) | 87 (76.3) |
| ALNR (%) | ||
| <35 | 135 (58.4) | 57 (50.0) |
| ≥35 | 96 (41.6) | 57 (50.0) |
| Radiation dose | ||
| Normal | 171 (74.0) | 84 (73.7) |
| High | 60 (26.0) | 30 (26.3) |
ALNR: Axillary lymph node ratio; BCS: Breast-conserving surgery; CR: Complete response; ER: Estrogen receptor; HER2: Human epidermal growth factor receptor 2; ISLN: Ipsilateral supraclavicular lymph node; ISLND: Ipsilateral supraclavicular lymph node dissection; NAC: Neoadjuvant chemotherapy; pCR: Pathological complete response; PD: Progressive disease; PR: Progesterone receptor; RECIST: Response evaluation criteria in solid tumors; SD: Stable disease.