Table 3.
Univariable and multivariable analyses of covariables associated with OS.
| Univariable Analysis | Multivariable Analysis | |||||
|---|---|---|---|---|---|---|
| Variable | HR | 95% CI | P | HR | 95% CI | P |
| an-WBRT vs. con-WBRT | 0.80 | 0.48–1.33 | 0.380 | 0.73 | 0.42–1.28 | 0.270 |
| Age | 1.00 | 0.98–1.02 | 0.946 | |||
| Sex | ||||||
| Male vs. female | 0.76 | 0.46–1.26 | 0.282 | |||
| Histology | ||||||
| Other vs. adenocarcinoma | 0.88 | 0.40–1.95 | 0.759 | |||
| Smoking status | ||||||
| Current/former vs. never | 0.86 | 0.52–1.42 | 0.546 | |||
| Stage at diagnosis | ||||||
| IV vs. I–III | 1.21 | 0.69–2.12 | 0.510 | |||
| Mutation type | ||||||
| EGFR 19/21 or ALK mutation vs. wild type or unknown | 2.36 | 1.38–4.01 | 0.002 | 1.90 | 1.06–3.41 | 0.030 |
| Line number of assigned treatment | ||||||
| Third or later vs. second | 1.78 | 1.05–3.02 | 0.031 | 1.55 | 0.88–2.73 | 0.127 |
| KPS | ||||||
| ≤ 60 vs. ≥ 70 | 2.40 | 1.36–4.23 | 0.002 | 2.34 | 1.32–4.17 | 0.004 |
| BM status | ||||||
| Newly diagnosed vs. progressive disease | 0.92 | 0.56–1.52 | 0.753 | |||
| Number of BMs | ||||||
| > 10 vs. 2–10 | 1.18 | 0.71–1.96 | 0.514 | |||
| Size of largest BM | 0.89 | 0.69–1.14 | 0.349 | |||
| BMs with cyst formation | ||||||
| No vs. Yes | 1.24 | 0.73–2.09 | 0.425 | |||
| Peritumoral edema from BMs | ||||||
| Moderate or severe vs. absent or mild | 0.80 | 0.48–1.33 | 0.385 | |||
| Extracranial metastases at time of intracranial progression | ||||||
| Yes vs. No | 1.22 | 0.67–2.23 | 0.511 | |||
| Number of extracranial metastatic organs | ||||||
| 3–7 vs. 0–2 | 1.46 | 0.88–2.43 | 0.142 | |||
| Number of extracranial lesions | ||||||
| ≥ 5 vs. 0–4 | 1.08 | 0.63–1.82 | 0.787 | |||
| Liver metastases | ||||||
| No vs. Yes | 0.66 | 0.36–1.23 | 0.191 | |||
| Primary NSCLC status | ||||||
| Uncontrolled vs. controlled or absent | 1.55 | 0.93–2.59 | 0.089 | |||
| Local boost at WBRT | ||||||
| Yes vs. No | 0.76 | 0.41–1.39 | 0.365 | |||
| Dexamethasone equivalent dose over WBRT | 1.00 | 1.00–1.00 | 0.954 | |||
| ICI combined with assigned treatment | ||||||
| Yes vs. No | 0.53 | 0.27–1.06 | 0.074 | |||
WBRT, whole-brain radiotherapy; KPS, Karnofsky Performance Status; brain metastases, BMs; NSCLC, non-small cell lung cancer; ICI, immune checkpoint inhibitor.