Table 2.

Univariate analysis on overall survival of clinical baseline prognostic factors

Variable	At risk	Events, n	1-year OS, %	P-valuea
Training cohort
Histology
Squamous	52	16	63.3	0.0683
Nonsquamous	148	56	59.6
ECOG PS
0-1	167	47	70.3	<0.001
2	33	25	17.1
BMI (kg/m2)
≥24.8	73	16	74.6	0.022
<24.8	94	36	59.2
Pretreatment steroids
Yes	40	23	37.1	<0.001
No	161	49	64.9
Brain metastases
Yes	31	16	42.7	0.028
No	170	56	63.8
Liver metastases
Yes	23	12	42.6	0.029
No	178	60	62.8
Validation cohort
Histology
Squamous	145	56	66.5	0.826
Nonsquamous	438	169	59.8
ECOG PS
0-1	488	167	66.3	<0.001
2	95	58	37.4
BMI (kg/m2)
≥24.8	246	89	65.6	0.123
<24.8	324	133	57.5
Pretreatment steroids
Yes	145	81	41.6	<0.001
No	438	144	68.2
Brain metastases
Yes	116	44	60.3	0.710
No	467	181	61.8
Liver metastases
Yes	76	38	50.8	0.034
No	507	187	63.2

BMI, body mass index; ECOG PS, Eastern Cooperative Oncology Group performance status; OS, overall survival.

Bold values indicate statistical significance.

^aLog-rank test.