TABLE 2.

Subgroup analysis of overall survival.

Subgroup analysis		No. of studies	HR	95%CI	p	Heterogeneity (I2) (%)
Line of therapy	First line	9	0.80	0.75–0.86	<0.001	33.2
	Non-first line	7	0.81	0.69–0.95	0.010	68.8
Therapeutic schedules	PD-1/PD-L1 + Chemotherapy vs. Chemotherapy	8	0.75	0.68–0.82	<0.001	46.0
	PD-1/PD-L1 vs. Chemotherapy	9	0.87	0.80–0.96	0.003	30.0
Tumour types	E	9	0.75	0.70–0.81	<0.001	3.4
	GEJ	7	0.87	0.76–0.99	0.040	0
	G	7	0.87	0.77–0.98	0.019	57.2
Histological type (E/GEJ)	Adenocarcinoma	2	0.92	0.61–1.38	0.679	73.3
	Squamous cell carcinoma	2	0.75	0.65–0.86	<0.001	0
Lauren classification (G/GEJ)	Intestinal type	5	0.80	0.71–0.92	0.001	12.9
	Diffuse type	5	0.84	0.72–0.99	0.032	43.7
Age	< 65 years	15	0.81	0.75–0.87	<0.001	20.4
	≥ 65 years	15	0.80	0.73–0.88	<0.001	32.7
ECOG performance status	0	14	0.82	0.73–0.91	<0.001	39.2
	1	14	0.78	0.71–0.86	<0.001	46.9
Sex	Male	15	0.78	0.72–0.84	<0.001	43.4
	Female	15	0.92	0.84–1.02	0.120	0
Geographical region	Asia	15	0.75	0.68–0.82	<0.001	44.2
	Non-Asia	10	0.90	0.83–0.97	0.006	17.2
TPS	TPS < 1%	8	0.89	0.80–0.99	0.030	3.0
	TPS ≥ 1%	9	0.69	0.58–0.83	<0.001	35.0
	TPS < 5%	4	0.78	0.68–0.89	<0.001	0
	TPS ≥ 5%	4	0.62	0.52–0.74	<0.001	0
	TPS < 10%	5	0.77	0.68–0.86	<0.001	0
	TPS ≥ 10%	4	0.66	0.52–0.83	<0.001	0
CPS	CPS < 1	4	0.91	0.72–1.15	0.416	0
	CPS ≥ 1	7	0.77	0.72–0.84	<0.001	0
	CPS < 5	2	0.87	0.70–1.08	0.221	29.7
	CPS ≥ 5	3	0.71	0.63–0.79	<0.001	0
	CPS < 10	5	0.86	0.74–0.99	0.038	22.3
	CPS ≥ 10	8	0.68	0.61–0.77	<0.001	0

HR, hazard ratio; CI, confidence interval; ECOG, Eastern Cooperative Oncology Group; PD-1, programmed death-1 receptor; PD-L1, programmed death ligand-1; TPS, PD-L1 tumour proportion score; CPS, PD-L1 combined positive score; E, esophageal cancer; GEJ, gastroesophageal junction cancer; G, gastric cancer.