Association between Tumor Vasculogenic Mimicry and the Poor Prognosis of Gastric Cancer in China: An Updated Systematic Review and Meta-Analysis

Table 3

Results of the subgroup analysis of the included studies.

Study subgroups	Number of studies	Number of patients	Pooled HR [95% CI]				Heterogeneity
			Fixed	value	Random	value	(%)	value
Study region
Coastal region	3	260	1.38 0.96, 1.99]	0.09	1.48 0.92, 2.39]	0.11	26	0.26
Inland	3	455	2.90 2.23, 3.78]	<0.00001	2.89 1.94, 4.30]	<0.00001	47	0.15
Methods of VM identification
PAS^+CD34^−	2	371	2.74 2.07, 3.64]	<0.00001	2.60 1.61, 4.19]	<0.0001	61	0.11
PAS^+CD31^−	4	344	1.72 1.24, 2.39]	0.001	2.10 1.07, 4.10]	0.03	70	0.02
Pathological type
Adenocarcinoma	5	688	2.30 1.84, 2.87]	<0.00001	2.36 1.44, 3.86]	0.0007	76	0.002
Sarcoma	1	27	1.67 0.72, 3.87]	0.03	1.67 0.72, 3.87]	0.23	Not applicable
Sample size ()
>100	3	544	2.13 1.68, 2.70]	<0.00001	1.96 1.04, 3.66]	0.04	85	0.001
<100	3	171	2.85 1.74, 4.67]	<0.0001	2.81 1.57, 5.05]	0.0005	27	0.26

VM, vasculogenic mimicry; OR, odds ratio; CI, confidence interval; HR, hazard ratio; PAS, periodic acid-Schiff.