Table 4.
Multivariable survival analyses stratified by age, adjusted for clinicopathological factors.
| LRFS | DFS | OS | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Hazard ratio | 95% CI | P-value | Hazard ratio | 95% CI | P-value | Hazard ratio | 95% CI | P-value | ||
| Age | ≤35 | Ref | Ref | Ref | ||||||
| 35~50 | 0.62 | 0.48~0.81 | <0.001 | 0.69 | 0.59~0.81 | <0.001 | 0.80 | 0.63~1.03 | 0.082 | |
| >50 | 0.65 | 0.50~0.85 | 0.002 | 0.80 | 0.68~0.95 | 0.010 | 1.13 | 0.88~1.44 | 0.345 | |
| T stage | 0–1 | Ref | Ref | Ref | ||||||
| 2 | 1.23 | 0.99~1.53 | 0.060 | 1.32 | 1.15~1.51 | <0.001 | 1.48 | 1.22~1.80 | <0.001 | |
| 3–4 | 1.49 | 1.12~1.99 | 0.007 | 2.00 | 1.69~2.38 | <0.001 | 2.65 | 2.10~3.34 | <0.001 | |
| N stage | 0 | Ref | Ref | Ref | ||||||
| 1 | 1.23 | 0.98~1.54 | 0.078 | 1.66 | 1.45~1.90 | <0.001 | 2.34 | 1.93~2.83 | <0.001 | |
| 2–3 | 1.96 | 1.55~2.47 | <0.001 | 3.32 | 2.91~3.78 | <0.001 | 5.87 | 4.87~7.08 | <0.001 | |
| LVI | Positive vs. negative | 1.35 | 1.09~1.69 | 0.007 | / | / | / | / | / | / |
| Ki67 | ≥15 vs. <15 | 1.52 | 1.24~1.91 | <0.001 | 1.31 | 1.15~1.48 | <0.001 | 1.38 | 1.15~1.65 | <0.001 |
| ER | Positive vs. negative | 0.62 | 0.51~0.75 | <0.001 | / | / | / | 0.81 | 0.66~1.00 | 0.048 |
| PR | Positive vs. negative | / | / | / | 0.80 | 0.71~0.89 | <0.001 | 0.77 | 0.63~0.94 | 0.009 |
| Surgical type | BCS vs. mastectomy | / | / | / | 0.80 | 0.71~0.91 | 0.001 | / | / | / |
| Chemotherapy | Yes vs. no | 0.68 | 0.51~0.91 | 0.010 | / | / | / | / | / | / |
| Radiotherapy | Yes vs. no | / | / | / | / | / | / | 0.50 | 0.43~0.59 | <0.001 |
ER, estrogen receptor; HER2, human epidermal growth factor receptor 2; PR, progesterone receptor; LVI, lymphovascular invasion; BCS, breast-conserving surgery; LRFS, local recurrence-free survival; DFS, disease-free survival; OS, overall survival; 95% CI, 95% confidence interval.