Table 2. The main results of pooled analyses.

Survival	Variables	NO. of studies	NO. of patients	P value			Regression model
				P H	P Z	P E	Random	Fixed
OS	All	16	1844	0.016	0.000	0.110	2.34 (1.77–3.09)	2.20 (1.82–2.66)
	Cancer type
	CRC	4	377	0.699	0.000	—	3.02 (1.84–4.95)	3.02 (1.84–4.95)
	ESCC	4	408	0.711	0.000	—	2.24 (1.67–3.01)	2.24 (1.67–3.01)
	Other	8	1059	0.001	0.006	—	2.18 (1.25–3.78)	1.95 (1.46–2.60)
	Ethnicity
	Asian	13	1351	0.894	0.000	—	2.43 (1.99–2.97)	2.43 (1.99–2.97)
	Caucasian	3	493	0.001	0.482	—	1.92 (0.31–11.91)	0.92 (0.51–1.67)
	Analysis method
	Univariable	4	277	0.329	0.000	—	2.53 (1.64–3.89)	2.13 (1.71–2.65)
	Multivarible	12	1567	0.009	0.000	—	2.26 (1.59–3.20)	2.44 (1.67–3.55)
	Specimen
	Tissue	15	1760	0.015	0.000	—	2.29 (1.72–3.04)	2.17 (1.79–2.63)
	Blood	1	84	—	0.037	—	4.96 (1.10–22.37)	4.96 (1.10–22.37)
MFS	All	3	421	0.080	0.000	—	2.81 (1.44–5.57)	2.32 (1.62–3.33)
RFS	All	3	506	0.000	0.369	—	1.98 (0.44–8.85)	1.96 (1.37–2.81)
DFS	All	2	141	0.969	0.001	—	3.29 (1.61–6.70)	3.29 (1.61–6.70)

P _H, P value of heterogeneity test; P _Z, P value of Z test; P _E, P value of Egger's test; CRC, colorectal cancer; ESCC, esophageal squamous cell carcinoma; OS, overall survival; MFS, metastasis-free survival; RFS, recurrence-free survival; DFS, disease-free survival.

Italic indicates HR with 95% CI used to analyses.

The bold represents statistically significant results.