Table 5.

Prognostic factors for overall survival after brain metastases in patients with lung cancer

Characteristics	Univariate analysis		Multivariate analysis
	X2	P-value	HR	95% CI	P-value
Age (years)
<65	2.397	0.122
≥65
Sex
Male	0.017	0.896
Female
ECOG
0	3.529	0.171
1
≥2
RPA classification
1	6.557	0.038
2
3
Prior WBRT	0.044	0.834
Yes
No
No. of brain metastases	3.356	0.340
1
2
3
≥4
Neurologic symptoms	0.389	0.533
Yes
No
Cystic brain metastases	1.33	0.249
Yes
No
Extracranial metastases
Yes	3.875	0.049
No
The volume of total BM (cm3)
≤8	10.937	0.004	1		0.001
8–27			1.108	0.802–1.532	0.533
>27			3.637	1.879–7.038	0.000
Primary tumor status
Control	5.500	0.019	1		0.003
Uncontrol			1.679	1.186–2.378

Abbreviations: BM, brain metastases; ECOG, Eastern Cooperative Oncology Group; RPA, recursive partitioning analysis; WBRT, whole brain radiotherapy.