Table 2.
Univariate and multivariate Cox regression analyses of covariables associated with survival after brain metastases.
| Univariate analyses | Multivariate analyses | |||
|---|---|---|---|---|
| HR (95%CI) | P-value | HR (95%CI) | P-value | |
| Age | ||||
| >65 vs. ≦65 | 1.35 (0.83 to 2.2) | 0.226 | ||
| Female vs. male | 0.5 (0.31 to 0.79) | 0.005 | 0.56 (0.34 to 0.9) | 0.017 |
| Initial Clinical stage | ||||
| III–IV vs. I–II | 1.25 (0.54 to 2.88) | 0.6 | ||
| Initial Tumor classification | ||||
| III–IV vs. I–II | 1.39 (0.83 to 2.33) | 0.208 | ||
| Initial Nodal classification | ||||
| 2–3 vs. 0–1 | 1.48 (0.93 to 2.35) | 0.097 | ||
| EGFR mutation | ||||
| Exon 19 or 21 | ||||
| Yes vs. no | 0.69 (0.38 to 1.26) | 0.225 | ||
| Exon 19 | ||||
| Yes vs. no | 0.63 (0.4 to 1) | 0.048 | 0.83 (0.51 to 1.35) | 0.461 |
| Exon 20 | ||||
| Yes vs. no | 0.95 (0.44 to 2.08) | 0.905 | ||
| Exon 21 | ||||
| Yes vs. no | 1.18 (0.75 to 1.85) | 0.47 | ||
| Brain surgery | ||||
| Yes vs. no | 0.6 (0.38 to 0.95) | 0.028 | 0.69 (0.43 to 1.12) | 0.134 |
| RT boost dose >3750 cGy | ||||
| Yes vs. no | 0.84 (0.53 to 1.32) | 0.441 | ||
| Number of lines of systemic chemotherapy | ||||
| >3 vs. 0–3 | 1.26 (0.63 to 2.53) | 0.519 | ||
| TKI name | ||||
| afatinib | ||||
| Yes vs. no | 0.56 (0.26 to 1.22) | 0.144 | ||
| erlotinib | ||||
| Yes vs. no | 0.72 (0.46 to 1.12) | 0.141 | ||
| gefitinib | ||||
| Yes vs. no | 1.43 (0.89 to 2.31) | 0.142 | ||
| osimertinib | ||||
| Yes vs. no | 0.68 (0.21 to 2.15) | 0.505 | ||
| Number of lines of TKI | ||||
| >1 vs. 1 | 0.8 (0.5 to 1.26) | 0.326 | ||
| ECOG performance status | ||||
| 1 vs. 0 | 1.03 (0.66 to 1.61) | 0.885 | ||
| 2 vs. 0 | 0.46 (0.11 to 1.91) | 0.287 | ||
| Smoking status | ||||
| Former or current vs. never | 1.39 (0.84 to 2.3) | 0.206 | ||
| Symptomatic brain metastases | ||||
| Yes vs. no | 1.13 (0.65 to 1.95) | 0.671 | ||
| Size of the largest brain tumor | ||||
| >1 cm vs. ≦1 cm | 1.51 (0.9 to 2.53) | 0.121 | ||
| No. of brain metastases | ||||
| 2–3 vs. 1 | 2.11 (0.95 to 4.93) | 0.068 | 1.83 (0.81 to 4.14) | 0.149 |
| >3 vs. 1 | 2.45 (1.24 to 4.72) | 0.01 | 2.23 (1.11 to 4.45) | 0.024 |
| dsGPA | ||||
| 0.5–1.5 vs. 2–4 | 1.6 (0.96 to 2.65) | 0.07 | ||
Abbreviations: EGFR: epidermal growth factor receptor; RT: radiation therapy; TKI: tyrosine kinase inhibitor; ECOG: Eastern Cooperative Oncology Group; dsGPA: disease-specific Graded Prognostic Assessment.