Table 1. Characteristics of eligible studies for meta-analysis.

Author	Year	Cancertype	Designtype	Survival	Studyquality*	GA No.	EA No.	HazardRatio	95% CI
Christopherson-I [6]	2008	Non-metastatic colon cancer	Prospective	Overall survival	7	92	85	0.216	0.065–0.718
Christopherson-II [6]	2008	Metastatic colon cancer	Prospective	Overall survival	7	92	85	0.699	0.395–1.236
Gupta-I [14]	2011	Colon cancer	Retrospective	Overall survival	6	93	360	0.82	0.30–2.19
Gupta-II [14]	2011	Rectal cancer	Retrospective	Overall survival	6	93	295	0.45	0.22–0.90
Lin [15]	2011	Ovarian cancer	Retrospective	Overall survival	6	37	106	0.824	0.699–0.930
Myles [16]	2011	Abdominal malignancies	Prospective	Overall survival	7	216	230	0.95	0.77–1.18
Cummings [17]	2012	Colon cancer	Retrospective	Overall survival	8	32,481	9,670	0.91	0.87–0.94
Exadaktylos [3]	2006	Breast cancer	Retrospective	Recurrence-free survival	6	79	50	0.21	0.06–0.71
Biki [2]	2008	Prostate cancer	Retrospective	Recurrence-free survival	6	123	102	0.43	0.22–0.83
Gottschalk [8]	2010	Colorectal cancer	Retrospective	Recurrence-free survival	7	253	256	0.82	0.49–1.35
Ismail [18]	2010	Cervical cancer	Retrospective	Recurrence-free survival	6	69	63	0.95	0.54–1.67
Luo [19]	2010	Colon cancer	Retrospective	Recurrence-free survival	7	931	182	1.326	0.940–1.871
Tsui [7]	2010	Prostate cancer	Prospective	Disease-free survival	6	50	49	1.33	0.64–2.77
Wuethrich [20]	2010	Prostate cancer	Retrospective	Progression-free survival	7	158	103	0.45	0.27–0.75
Myles [16]	2011	Abdominal malignancies	Prospective	Recurrence-free survival	7	216	230	0.95	0.76–1.17
Oliveira Jr [21]	2011	Ovarian Cancer	Retrospective	Recurrence-free survival	7	127	55	0.37	0.19–0.73
Lai [22]	2012	Hepatocellular carcinoma	Retrospective	Recurrence-free survival	7	117	62	3.66	2.59–5.15
Cummings [17]	2012	Colon cancer	Retrospective	Recurrence-free survival	8	31,099	9,278	1.05	0.95–1.15

^*evaluated by the 9-star Newcastle-Ottawa Scale.