Table 4.

Multivariate analysis of survival

Variable	RR	95% CI	P-value
Age	1.64	0.77–3.51	0.199
Gender	1.72	0.70–4.19	0.235
Histology	2.64	0.95–7.32	0.062
RPA	2.01	0.91–4.44	0.084
Number of brain metastases	1.20	0.54–2.67	0.650
Primary tumor	2.70	0.91–8.03	0.074
Treatment modality	15.32	3.53–66.51	<0.001
B7-H4 expression	3.46	1.52–7.85	0.003

Abbreviations: CI, confidence interval; RPA, recursive partitioning analysis; RR, relative risk.