Table 3.
Multivariable analysis of overall survival and progression-free survival after BLMM in patients with BLMM (n = 4727)
| OS (n = 4474) |
PFS (n = 3385) |
|||
|---|---|---|---|---|
| HR (95% CI) | P value | HR (95% CI) | P value | |
| HER2 status | ||||
| HER2-low | 1.00 | 1.00 | ||
| HER2− | 1.08 (1.00-1.17) | 0.0485 | 1.01 (0.93-1.11) | 0.7443 |
| HER2+ | 0.39 (0.35-0.43) | <0.0001 | 0.56 (0.51-0.62) | <0.0001 |
| Age at BLMM diagnosis, years | ||||
| <50 | 1.00 | 1.00 | ||
| 50-70 | 1.15 (1.06-1.24) | 0.0006 | 0.95 (0.88-1.03) | 0.2393 |
| >70 | 1.64 (1.47-1.82) | <0.0001 | 0.99 (0.88-1.12) | 0.9206 |
| Histological grade | ||||
| Grade I/II | 1.00 | 1.00 | ||
| Grade III | 1.06 (0.98-1.14) | 0.1300 | 1.10 (1.02-1.18) | 0.0146 |
| Number of metastatic sites | ||||
| <3 sites | 1.00 | 1.00 | ||
| ≥ 3 sites | 1.16 (1.07-1.24) | 0.0001 | 1.21 (1.12-1.31) | <0.0001 |
| Metastasis-free interval (MFI), months | ||||
| <6 | 1.00 | 1.00 | ||
| 6-24 | 1.41 (1.27-1.57) | <0.0001 | 1.44 (1.29-1.61) | <0.0001 |
| >24 | 0.97 (0.90-1.05) | 0.5061 | 1.00 (0.92-1.09) | 0.9078 |
| Hormone receptor status | ||||
| Negative | 1.00 | 1.00 | ||
| Positive | 0.73 (0.67-0.78) | <0.0001 | 0.82 (0.76-0.89) | <0.0001 |
| Interval from mBC to BLMM, months | ||||
| 0-1 | 1.00 | 1.00 | ||
| 1-12 | 2.12 (1.92-2.33) | <0.0001 | 1.77 (1.60-1.94) | <0.0001 |
| >12 | 2.30 (2.10-2.52) | <0.0001 | 1.79 (1.64-1.96) | <0.0001 |
Of the 4727 patients who developed a BLMM, 253 patients were excluded from the multivariable analysis for missing data on histological grade and MFI. For the PFS analysis, 1089 patients without treatment line after dBLMM were also excluded.
Bold = P value <0.05, significative value.
BLMM, brain and leptomeningeal metastases; CI, confidence interval; dBLMM, first BLMM diagnosis; HR, hazard ratio; HER2, human epidermal growth factor receptor 2; mBC, metastatic breast cancer; OS, overall survival; PFS, progression-free survival.