Cell-free DNA liquid biopsy for early detection of gastrointestinal cancers: A systematic review

Table 1 Characteristics of included studies

Ref.	Year	Country	Mono/multicentric	Type of cancer	Total number of patients in validation cohort	Type of groups analyzed
Li et al[13]	2020	China	Monocentric	PDAC	208	Cancer vs healthy
Chen et al[14]	2020	China	Monocentric	Gastric, esophagus, colorectal, lung or liver	418	Cancer diagnosed vs healthy; Pre-diagnosed patients vs healthy
Guler et al[18]	2020	United States	Multicentric	PDAC	228	Cancer vs healthy
Junca et al[12]	2020	France	NA	Colorectal	130	Cancer vs healthy vs advanced-adenoma vs non-advanced adenoma and/or hyperplastic polyp(s)
Tao et al[15]	2020	China	NA	HCC	175	HBV-related HCC vs cancer-free HBV patients
Cristiano et al[19]	2019	United States	Multicentric	Breast, colorectal, lung, ovarian, pancreatic, gastric, bile duct	423	Cancer vs healthy
Li et al[17]	2019	China	Monocentric	Colorectal	140	Cancer vs healthy
Qu et al[16]	2019	China	Multicentric	HCC	331	HBsAg1 positive without cancer based on screening with serum AFP and ultrasonography
Cai et al[11]	2019	China	Multicentric	HCC	1194	Cancer vs healthy vs 392 LC/HB vs BLL
Wan et al[9]	2019	United States	Multicentric	Colorectal	817	Cancer vs healthy
Jensen et al[20]	2019	Denmark	NA	Colorectal	234	Cancer vs healthy
Nunes et al[21]	2018	Portugal	NA	Breast, colorectal, lung	356	Cancer vs healthy
Perrone et al[22]	2014	Italy	Monocentric	Colorectal	170	Cancer vs healthy vs premalignant lesion (adenoma/hyperplasia)

PDAC: Pancreatic ductal adenocarcinoma; HCC: Hepatocellular carcinoma; LC/HB: Liver cirrhosis/hepatitis B; BLL: Benign liver lesions; HBV: Hepatitis B virus; AFP: Alpha-fetoprotein.