Table 1. Main characteristics of eligible studies.

Author	Year	Country	N	Cancer	Stage	Adjuvant therapy	Source	Method	Cut-off criteria	Cut-off value	Analyze method	HR	Survival analysis
Huang et al.	2016	China	191	NPC	I–IV	RT, CCRT	tumor, LYM	IHC	median	H-score of 0.7	MVA	report	OS
Roncella et al.	2016	Italy	45	MPM	I–IV	NM	blood, tumor	IHC, ELISA	median	S->66 PE->67	MVA	report	OS
Fukuda et al.	2016	Japan	181	renal cancer	I–IV	targeted therapy	blood	ELISA	NM	NM	UA	DE	OS
Zhang et al.	2015	China	158	esophageal cancer	I–IV	NM	tumor	IHC	mean	H-score of 2–4	MVA	report	OS
Yu et al.	2015	China	130	breast cancer	I–IIIC	RT, CT, ET	tumor; LYM	IHC	ROC curve	H-score of 1.525	MVA	report	OS
Teng et al.	2015	China	62	rectal cancer	III–IV	CCRT	Tumor	IHC	NM	H score of 20	UA	Report	OS
Sengsayadeth et al.	2014	America	780	hematological cancer	NM	HSCT	SNP	PCR	NM	NM	MVA	K-M	OS
Fong et al.	2013	America	24	glioblastoma	NM	immunotherapy	LYM	FC	RPA	1.047:0.8065	UA	report	OS
Salvi et al.	2012	Italy	81	LC	I–IIIB	None	tumor	IHC	median	H-score of 20	MVA	report	OS
Jagasia et al.	2012	America	164	hematological cancer	NM	HSCT	SNP	PCR	NM	NM	MVA	report	OS
Wang et al.	2012	UK	284	melanoma	II–III	IFN-a Therapy	tumor	PCR	median	NM	MVA	report	OS
Xiao et al.	2012	China	240	hematological cancer	NM	immunotherapy	SNP	PCR	NM	NM	MVA	K-M	OS
Song et al.	2011	China	338	LC	IIIB–IV	RT, CT, CRT	SNP	PCR	N/A	N/A	MVA	report	OS
Pe´rez-Garcı´a et al.	2009	Spain	143	AML	NM	CT	SNP	PCR	NM	NM	MVA	Report	OS
Erfani et al.	2013	Iran	72	laryngeal cancer	I–IV	None	LYM	FCM	N/A	N/A	N/A	N/A	N/A
Erfani et al.	2012	Iran	39	LC	II–IV	None	LYM	FCM	N/A	N/A	N/A	N/A	N/A

N, number; OS, overall survival; HR, hazard ratio; MVA, multivariate analysis; UA, univariate analysis; PCR, polymerase chain reaction; IHC, immunohistochemistry; N/A, not applicable; H score, histochemical score; RPA, recursive partitioning analysis; NPC, nasopharyngeal cancer; MPM, malignant pleural mesothelioma; LC, lung cancer; AML, acute myelocytic leukemia; RT, radiotherapy; CT, chemotherapy; CCRT, concurrent chemoradiotherapy; ET, endocrine therapy; HSCT, hematopoietic stem cell transplantation; SNP, single nucleotide polymorphisms; LYM, lymphocyte; FCM, flow cytometry; DE, data extrapolated.