Table 2.
Multivariable analysis for breast cancer-specific mortality among the Z0011-comparable patients.
| Variable | Univariable Analysis | Multivariable Analysis a | ||
|---|---|---|---|---|
| HR (95% CI) | p-Value | HR (95% CI) | p-Value | |
| Extent of axillary clearance | ||||
| SLND vs. SLND + ALND | 0.884 (0.743–1.051) | 0.163 | 1.065 (0.821–1.382) | 0.636 |
| Age | ||||
| >50 vs. ≤50 | 1.052 (0.897–1.234) | 0.532 | ||
| No. of metastatic ALN(s) | ||||
| 2 vs. 1 | 1.335 (1.154–1.545) | <0.001 | 1.285 (1.025–1.611) | 0.030 |
| Node status | ||||
| macro- vs. micro-metastasis | 1.534 (1.300–1.811) | <0.001 | 1.279 (1.076–1.521) | 0.005 |
| T category | ||||
| T2 vs. T1 | 2.469 (2.152–2.832) | <0.001 | 1.856 (1.612–2.137) | <0.001 |
| Histologic grade | ||||
| 2 vs. 1 | 2.132 (1.571–2.893) | <0.001 | 1.800 (1.323–2.449) | <0.001 |
| 3 vs. 1 | 6.360 (4.746–8.522) | <0.001 | 3.463 (2.534–4.733) | <0.001 |
| Histologic type | ||||
| ILC vs. IDC | 0.747 (0.551–1.012) | 0.060 | 1.098 (0.802–1.504) | 0.559 |
| IDC and ILC vs. IDC | 0.664 (0.481–0.916) | 0.013 | 0.938 (0.676–1.300) | 0.699 |
| others vs. IDC | 0.924 (0.699–1.221) | 0.579 | 0.857 (0.648–1.133) | 0.278 |
| ER status | ||||
| positive vs. negative | 0.248 (0.216–0.285) | <0.001 | 0.618 (0.505–0.758) | <0.001 |
| PR status | ||||
| positive vs. negative | 0.274 (0.239–0.313) | <0.001 | 0.509 (0.419–0.618) | <0.001 |
| HER2 status | ||||
| positive vs. negative | 1.043 (0.856–1.272) | 0.676 | ||
| Adjuvant chemotherapy | ||||
| no vs. yes | 0.869 (0.757–0.998) | 0.047 | 1.492 (1.284–1.734) | <0.001 |
| Adjuvant radiotherapy | ||||
| no vs. yes | 1.948 (1.699–2.233) | <0.001 | 1.493 (1.186–1.881) | 0.001 |
| No. of metastatic ALN(s) ×Extent of axillary clearance (2 vs. 1) | 0.008 b | |||
| SLND vs. SLND + ALND | 1.594 (1.046–2.429) | 0.030 | ||
| Adjuvant radiotherapy×Extent of axillary clearance (no vs. yes) | 0.023 b | |||
| SLND vs. SLND + ALND | 1.418 (0.998–2.014) | 0.052 | ||
Abbreviations: axillary lymph node (ALN); axillary lymph node dissection (ALND); confidence interval (CI); estrogen receptor (ER); human epidermal growth factor receptor 2 (HER2); hazard ratio (HR); invasive ductal carcinoma (IDC); invasive lobular carcinoma (ILC); progesterone receptor (PR); sentinel lymph node dissection (SLND). a Variables with p < 0.1 in univariable analyses and the extent of axillary clearance were inputted into multivariable analysis. b Interaction p-values.