Table 6. Univariate and multivariate analyses of the tumor-specific survival rates.
| Variables | Cox univariate analysis | Cox multivariate analysis | |||
|---|---|---|---|---|---|
| HR (95% CI) | P value | HR (95% CI) | P value | ||
| Age (years) | |||||
| ≤40 | |||||
| >40 | 0.257 (0.068–0.969) | 0.045 | 0.373 (0.096–1.452) | 0.129 | |
| Pathological types | |||||
| Ductal | |||||
| Others | 1.938 (0.514–7.307) | 0.329 | |||
| T stage | |||||
| T1 | |||||
| T2 | 5.835 (1.548–21.999) | 0.009 | 4.659 (1.23–17.599) | 0.023 | |
| N stage | |||||
| N0 | |||||
| N1 | 4.177 (1.221–14.284) | 0.023 | 5.561 (1.431–21.614) | 0.013 | |
| Hormone status | |||||
| ER (+) and/or PR (+) | |||||
| ER (−) combined with PR (−) | 0.8010 (0.234–2.732) | 0.721 | |||
| Side of the tumor | |||||
| Left | |||||
| Right | 0.929 (0.283–3.044) | 0.903 | |||
| Radiotherapy approach | |||||
| HF | |||||
| CF | 0.817 (0.249–2.677) | 0.738 | 0.574 (0.163–2.020) | 0.387 | |
| HER2 expression | |||||
| Negative | |||||
| Positive | 4.286 (1.307–14.058) | 0.016 | 0.017 (1.339–18.331) | 0.017 | |
HF, hypofractionated radiotherapy; CF, conventional fractioned radiotherapy; HER2, human epidermal growth factor receptor; HR, hazard ratio; CI, confidence interval.