Table 2. Multivariate logistic regression analysis of predictive factors of brain metastasis in training set.
| Variables | OR | 95% CI | P value |
|---|---|---|---|
| Age | 0.025 | ||
| <45 | Reference | Reference | |
| 45–64 | 1.541 | 1.064–2.230 | 0.022 |
| >64 | 1.178 | 0.790–1.759 | 0.422 |
| Grade | 0.964 | ||
| I | Reference | Reference | |
| II | 1.157 | 0.647–2.068 | 0.622 |
| III | 1.172 | 0.647–2.124 | 0.601 |
| IV | 1.167 | 0.244–5.582 | 0.846 |
| Histological type | 0.513 | ||
| IDC | Reference | Reference | |
| ILC | 0.850 | 0.500–1.443 | 0.546 |
| Others | 0.737 | 0.414–1.312 | 0.300 |
| Tumor size (cm) | 0.081 | ||
| ≤2 | Reference | Reference | |
| >2 and ≤5 | 0.694 | 0.491–0.982 | 0.039 |
| >5 | 0.860 | 0.607–1.217 | 0.394 |
| Subtype | 0.001 | ||
| HR+, HER2− | Reference | Reference | |
| HR+, HER2+ | 1.286 | 0.922–1.793 | 0.139 |
| HR−, HER2+ | 1.558 | 1.050–2.313 | 0.028 |
| HR−, HER2− | 1.921 | 1.376–2.681 | <0.001 |
| Liver metastasis | |||
| No | Reference | Reference | |
| Yes | 1.280 | 0.988–1.658 | 0.061 |
| Lung metastasis | |||
| No | Reference | Reference | |
| Yes | 1.855 | 1.450–2.375 | <0.001 |
OR, odds ratio; CI, confidence interval; IDC, invasive ductal carcinoma; ILC, invasive lobular carcinoma; HR, hormone receptor; HER2, human epidermal growth factor receptor 2.