Table 4 Cox proportional hazard model analysis of factors affecting patient overall survival (n = 41)

Age (≥ 60 vs.<60 year)

0.279

0.649

0.297–1.419

0.745

—

—

Sex (female vs. male)

0.513

1.296

0.596–2.821

0.273

—

—

ECOG PS (<2 vs.≥2)

0.013*

2.862

1.246–6.575

0.048*

2.560

1.010–6.484

Brain metastasis (no vs. yes)

0.969

1.018

0.405–2.562

0.644

—

—

Gene mutation (no vs. yes)^a

0.840

1.100

0.437–2.765

0.739

—

—

Combined with BEV (no vs. yes)

0.022*

0.404

0.186–0.877

0.002*

0.240

0.097–0.595

CSF protein (Normal vs. Increased)

0.102

3.427

0.782–15.011

0.064

—

—

Number of IC

0.202

0.948

0.873–1.029

0.813

—

—