Table 6.
Final multivariate Cox analysis of breast cancer–free survival with four-biomarker definition of intrinsic subtypes a
| Variables | HR | 95% CI | P b |
|---|---|---|---|
| Tumor size, cm | |||
| <2 |
1.0 |
|
|
| 2 to 5 |
1.6 |
1.2 to 2.1 |
0.0004 |
| >5 |
1.9 |
1.2 to 3.1 |
0.005 |
| Lymph nodes | |||
| 0 |
1.0 |
|
|
| 1 to 3 |
1.4 |
1.0 to 1.8 |
0.01 |
| ≥4 |
2.8 |
2.1 to 3.7 |
<0.0001 |
| Local therapy | |||
| Mastectomy alone |
1.0 |
|
|
| Mastectomy + RT |
1.1 |
0.7 to 1.5 |
0.6 |
| Lumpectomy alone |
1.2 |
0.6 to 2.1 |
0.5 |
| Lumpectomy + RT |
0.6 |
0.4 to 0.8 |
0.0005 |
| Endocrine therapy | |||
| Yes |
1.0 |
|
|
| No |
0.7 |
0.5 to 0.9 |
0.01 |
| Subtype | |||
| Luminal A |
1.0 |
|
|
| Luminal B |
1.3 |
1.0 to 1.7 |
0.02 |
| HER2-enriched |
1.4 |
1.0 to 2.0 |
0.04 |
| Triple-negative | 1.3 | 0.9 to 1.8 | 0.09 |
aCI, confidence interval; HER2, human epidermal growth factor receptor 2; HR, hazard ratio; RT, radiotherapy. bAll likelihood ratio, Wald and logrank statistical tests were two-sided.