Table 2.
Univariate and multivariate COX regressions for the factors associated with OS before PSM
| Univariate COX regression analysis | Multivariate COX regression analysis | |||||
|---|---|---|---|---|---|---|
| Hazard Ratio | 95% CI | P value | Hazard Ratio | 95% CI | P value | |
| Age | 0.99 | 0.96–1.02 | 0.529 | NA | NA | NA |
| Gender | ||||||
| Female | Reference | |||||
| Male | 1.38 | 0.72–2.65 | 0.332 | NA | NA | NA |
| PS score | ||||||
| 1 | Reference | |||||
| 2 | 0.92 | 0.47–1.81 | 0.804 | NA | NA | NA |
| Driver gene | ||||||
| None | Reference | |||||
| Yes | 0.71 | 0.35–1.41 | 0.328 | NA | NA | NA |
| Unknown | 1.30 | 0.78–2.16 | 0.322 | NA | NA | NA |
| Pathological type | ||||||
| Adenocarcinoma | Reference | |||||
| Squamous carcinoma | 2.20 | 1.13–4.28 | 0.021 | 2.59 | 1.31–5.13 | 0.006 |
| NSCLC (NOS) | 0.29 | 0.04–2.09 | 0.217 | 0.29 | 0.04–2.13 | 0.225 |
| Primary lesion | ||||||
| Left lung | Reference | |||||
| Right lung | 0.87 | 0.53–1.43 | 0.593 | NA | NA | NA |
| T stage | ||||||
| T1 | Reference | |||||
| T2 | 0.74 | 0.31–1.76 | 0.493 | NA | NA | NA |
| T3 | 1.05 | 0.44–2.51 | 0.912 | NA | NA | NA |
| T4 | 1.67 | 0.75–3.72 | 0.206 | NA | NA | NA |
| N stage | ||||||
| N0 | Reference | |||||
| N1 | 0.25 | 0.03–1.87 | 0.177 | NA | NA | NA |
| N2 | 1.22 | 0.66–2.27 | 0.528 | NA | NA | NA |
| N3 | 1.05 | 0.53–2.09 | 0.882 | NA | NA | NA |
| Extracranial metastases | ||||||
| None | Reference | |||||
| Yes | 1.12 | 0.68–1.84 | 0.654 | NA | NA | NA |
| Number of BM | ||||||
| >=3 | Reference | |||||
| 1 | 1.23 | 0.72–2.11 | 0.443 | NA | NA | NA |
| 2 | 1.06 | 0.49–2.26 | 0.884 | NA | NA | NA |
| Size of BM | ||||||
| < 10 | Reference | |||||
| >=10, < 20 | 0.97 | 0.48–1.99 | 0.942 | NA | NA | NA |
| >=20,<30 | 1.02 | 0.45–2.33 | 0.958 | NA | NA | NA |
| >=30 | 1.11 | 0.49–2.49 | 0.800 | NA | NA | NA |
| Smoking history | ||||||
| None | Reference | |||||
| Yes | 1.95 | 1.16–3.30 | 0.013 | 1.75 | 1.02–2.99 | 0.043 |
| Treatment modality | ||||||
| ICI + RT | Reference | |||||
| CT + RT | 1.86 | 1.14–3.06 | 0.014 | 1.82 | 1.09–3.05 | 0.023 |
| Type of brain radiotherapy | ||||||
| WBRT | Reference | |||||
| SRS | 1.19 | 0.72–1.95 | 0.497 | NA | NA | NA |
| Sequence of treatment | ||||||
| Upfront brain RT | Reference | |||||
| Upfront ICI/CT | 1.31 | 0.56–3.05 | 0.532 | NA | NA | NA |
| Symptoms of BM | ||||||
| None | Reference | |||||
| Yes | 1.30 | 0.78–2.16 | 0.321 | NA | NA | NA |
| Surgery of lung | ||||||
| None | Reference | |||||
| Yes | 0.98 | 0.56–1.71 | 0.940 | NA | NA | NA |
BM, brain metastasis; CT, chemotherapy; ICI, immune checkpoint inhibitor; NSCLC, non-small Cell Lung Cancer; NOS, not otherwise specified; OS, overall survival; PSM, propensity score matching; RT, radiotherapy; SRS, stereotactic radiosurgery; WBRT, whole-brain radiation therapy