Table 2.
Univariable and multivariable analyses of covariables associated with iPFS.
| Univariable Analysis | Multivariable Analysis | |||||
|---|---|---|---|---|---|---|
| Variable | HR | 95% CI | P | HR | 95% CI | P |
| an-WBRT vs. con-WBRT | 0.60 | 0.37–0.98 | 0.043 | 0.57 | 0.33–0.99 | 0.044 |
| Age | 0.99 | 0.97–1.01 | 0.364 | |||
| Sex | ||||||
| Male vs. female | 0.67 | 0.41–1.09 | 0.105 | |||
| Histology | ||||||
| Other vs. adenocarcinoma | 0.96 | 0.44–2.10 | 0.909 | |||
| Smoking status | ||||||
| Current/former vs. never | 0.79 | 0.48–1.28 | 0.335 | |||
| Stage at diagnosis | ||||||
| IV vs. I–III | 1.16 | 0.68–1.97 | 0.595 | |||
| Mutation type | ||||||
| EGFR 19/21 or ALK mutation vs. wild type or unknown |
1.81 | 1.09–3.01 | 0.021 | 1.28 | 0.73–2.24 | 0.389 |
| Line number of assigned treatment | ||||||
| Third or later vs. second | 1.68 | 1.02–2.79 | 0.043 | 1.70 | 0.98–2.94 | 0.058 |
| KPS | ||||||
| ≤ 60 vs. ≥ 70 | 1.76 | 1.04–2.99 | 0.036 | 1.63 | 0.95–2.78 | 0.076 |
| BM status | ||||||
| Newly diagnosed vs. progressive disease | 0.85 | 0.53–1.39 | 0.523 | |||
| Number of BMs | ||||||
| > 10 vs. 2–10 | 1.23 | 0.76–1.99 | 0.390 | |||
| Size of largest BM | 0.84 | 0.66–1.07 | 0.157 | |||
| BMs with cyst formation | ||||||
| No vs. Yes | 1.24 | 0.75–2.07 | 0.402 | |||
| Peritumoral edema from BMs | ||||||
| Moderate or severe vs. absent or mild | 0.71 | 0.44–1.15 | 0.164 | |||
| Extracranial metastases at time of intracranial progression | ||||||
| Yes vs. No | 1.27 | 0.71–2.26 | 0.419 | |||
| Number of extracranial metastatic organs | ||||||
| 3–7 vs. 0–2 | 0.99 | 0.61–1.62 | 0.979 | |||
| Number of extracranial lesions | ||||||
| ≥ 5 vs. 0–4 | 1.12 | 0.67–1.87 | 0.661 | |||
| Liver metastases | ||||||
| No vs. Yes | 0.83 | 0.46–1.49 | 0.527 | |||
| Primary NSCLC status | ||||||
| Uncontrolled vs. controlled or absent | 1.44 | 0.88–2.34 | 0.146 | |||
| Local boost at WBRT | ||||||
| Yes vs. No | 1.06 | 0.59–1.89 | 0.846 | |||
| Dexamethasone equivalent dose over WBRT | 1.00 | 1.00–1.01 | 0.162 | |||
| ICI combined with assigned treatment | ||||||
| Yes vs. No | 0.62 | 0.33–1.17 | 0.142 | |||
WBRT, whole-brain radiotherapy; KPS, Karnofsky Performance Status; brain metastases, BMs; NSCLC, non-small cell lung cancer; ICI, immune checkpoint inhibitor.