Table 2. Multivariate analysis of OS for the whole study population (n = 1560).
| Factors | HR | 95% CI | P |
|---|---|---|---|
| Age, years | |||
| ≤40 | Reference | ||
| 41-60 | 1.209 | 0.857-1.706 | 0.281 |
| >60 | 1.692 | 1.122-2.553 | 0.012 |
| Race | |||
| White | Reference | ||
| Black | 0.965 | 0.701-1.329 | 0.829 |
| Asian or other | 0.394 | 0.174-0.894 | 0.026 |
| Insurance status | |||
| Private insurance | Reference | ||
| Public insurance | 1.468 | 1.093-1.971 | 0.011 |
| Not insured | 1.155 | 0.645-2.068 | 0.627 |
| Unknown | 1.176 | 0.423-3.270 | 0.756 |
| Histologic grade | |||
| Well differentiated | Reference | ||
| Moderately differentiated | 9.749 | 1.331-71.425 | 0.025 |
| Poorly or undifferentiated | 7.760 | 1.066-56.489 | 0.043 |
| Unknown | 9.221 | 1.239-68.657 | 0.030 |
| Examined regional nodes number | |||
| 0-10 | Reference | ||
| >10 | 0.770 | 0.598-0.991 | 0.043 |
| Unkown | 1.196 | 0.576-2.482 | 0.631 |
| Clinical T-stage | |||
| T1 | Reference | ||
| T2 | 0.692 | 0.419-1.141 | 0.149 |
| T3 | 1.575 | 0.784-3.167 | 0.202 |
| T4 | 2.808 | 1.395-5.649 | 0.004 |
| Clinical AJCC stage | |||
| II | Reference | ||
| III | 2.193 | 1.197-4.017 | 0.011 |
| Pathologic T-stage (after NAC) | |||
| T0/Tis | Reference | ||
| T1 | 1.275 | 0.943-1.724 | 0.115 |
| T2 | 1.599 | 1.160-2.205 | 0.004 |
| Hormone therapy | |||
| No | Reference | ||
| Yes | 0.647 | 0.441-0.951 | 0.027 |
| Unknown | 0.618 | 0.300-1.273 | 0.192 |
| PMRT | |||
| No | Reference | ||
| Yes | 0.820 | 0.630-1.068 | 0.141 |
Abbreviations: OS, overall survival; HR, hazard ratio; CI, confidence interval; AJCC, American Joint Committee on Cancer (fifth or sixth edition); NAC, neoadjuvant chemotherapy; PMRT, postmastectomy radiotherapy