Table 3.

Baseline characteristics of the cancer-dead and survival patients

	Cancer death	Survival	P value
Total (n)	118	132	–
Age (n)	64.2 ± 5.5	64.7 ± 6.1	0.573
Gender (n)
Female	23	30	0.532
Male	95	102
Smoking history (n)
Non-smoker	47	60	0.370
Smoker	71	72
Performance status
0–1	98	120	0.063
2	20	12
Tumor grade (n)
High-middle	83	110	0.014
Low	35	22
Tumor stage (n)
LDa	57	86	0.007
EDa	61	46
EGFR (n)a
Negative	90	112	0.086
Positive	28	20
KRAS (n)a
Negative	107	127	0.074
Positive	11	5
Chemotherapeutic response (n)
Response	12	126	<0.001
Non-response	106	6
Serum PD-L1 (ng/ml)a	7.6 ± 3.1	6.5 ± 2.7	0.003

^aLD Limited disease, ED Extensive disease, EGFR Epidermal growth factor receptor, KRAS Kirsten rat sarcoma viral oncogene, PD-L1 Programmed death ligand 1