Table 1.

Main characteristics of all studies included in Meta-analysis

First author (Ref.)	Year	Country	Kind	NO of Case (control)	Method	Clinicopathological factors	Quality score
YANG [5]	2010	China	HCC	67 (28)	SC	①②⑤	7
Qi [8]	2009	China	CRC	100 (100)	IHC/RT-PCR	⑤	7
AO [9]	2013	China	EC	150 (30)	IHC	①②④⑤	7
Li [10]	2005	China	EC	28 (40)	IHC	②	6
Xiong [11]	2010	China	EC	109 (109)	RT-PCR	②③④	7
Yusushi [12]	2002	Japan	GC	84	RT-PCR	③⑤	6
Chen [13]	2008	China	GC	79 (42)	IHC	①②③⑤	8
Yang [14]	2012	China	GC	50 (50)	RT-PCR	①②	7
Liu [15]	2008	China	CC	66	IHC	①②③	5
Zhu [16]	2011	China	CRC	60 (10)	IHC	②③④	6
Li [6]	2008	China	CRC	100 (100)	IHC	②③	8
Yang [17]	2008	China	CRC	101 (21)	IHC	②③④	8
Cai [18]	2010	China	CG	38 (42)	IHC	①②③④	8
Chen [19]	2009	China	HCC	40 (20)	RT-PCR	①③⑤	6
Shen [20]	2003	China	HCC	48 (48)	RT-PCR	⑤	6
Chen [21]	2007	China	HCC	69 (69)	RT-PCR	①②⑤	6
Yu [22]	2005	China	GC	62 (62)	RT-PCR	②③④	8
Zhang [23]	2009	China	CRC	70 (10)	IHC	②	8
Cui [24]	2012	China	HCC	40 (40)	IHC	②	6
Liu [25]	2011	China	EC	84 (84)	IHC	①②③④	5
Zhang [26]	2010	China	GC	60 (30)	IHC	②③④	5
Yue [27]	2010	China	EC	98 (20)	IHC	①②③④	6
Li [28]	2004	China	GC	98 (56)	IHC	①②③④	7
Zhao [29]	2009	China	GC	75 (15)	IHC	①③④	7
Guo [30]	2009	China	GC	86 (86)	RT-PCR	①②③④	7
Zhou et al. [31]	2012	China	PC	50 (50)	RT-PCR	①③	6
Shen et al. [32]	2005	China	HCC	48 (48)	RT-PCT	①⑤	7
Liu et al. [33]	2013	China	CRC	62 (62)	IHC	①②③④	6

HCC, hepatocellular carcinoma; CRC, colorectal cancer; EC, esophageal cancer; GC, gastric carcinoma; PC, pancreatic carcinoma; CG, carcinoma of gallbladder; IHC, immunohistochemistry; SC, serum concentration; ①TNM stage; ②differentiation; ③lymph node metastasis; ④infiltration degree; ⑤metastasis.