Significance of carcinoembryonic antigen detection in the early diagnosis of colorectal cancer: A systematic review and meta-analysis

Table 1 Characteristics of included studies

Ref.	Year of publication	Study design	Sample size	Age (yr)	Location of cancer	Stage of the tumour	Treatment therapy
Augestad et al[15]	2014	Randomized controlled trial	110	65.4 ± 8.1; males = 59.1%, females = 40.9%	Colon (110 patients)	I (24), II (55), III (32)	Surgical treatment for all patients
Bhatti et al[16]	2015	Prospective cohort study	569	70; males = 51%, females = 49%	Colon (336 patients) and rectum (233 patients)	0 (31), I (33), II (78), III (288), IV (137)	Surgical treatment (569 patients), neoadjuvant chemotherapy (106 patients) and adjuvant chemotherapy (204 patients)
Chang et al[17]	2017	Prospective cohort study	357	63.8 ± 11.5; males = 57.7%, females = 42.3%	Colon (259 patients) and rectum (98 patients)	I (97), II (125), III (135)	Surgical treatment (357 patients), neoadjuvant radiotherapy and chemotherapy (81 patients)
Gilardoni et al[18]	2015	Retrospective cohort study	196	70; males = 59.7%, females = 40.3%	Colon (196 patients)	I (65), III (131)	Surgical treatment (196 patients)
Guo et al[19]	2018	Retrospective cohort study	178	59.7 ±10.6; males = 66.3%; females = 32.7%	Colon (79 patients) and rectum (42 patients)	0 (2), I (11), II (60), III (105)	Surgical treatment (178 patients) and chemotherapy (66 patients)
Hara et al[20]	2011	Prospective cohort study	127	63.4 ±9.4; males = 55.1%, females = 44.9%	Colon (85 patients) and rectum (42 patients)	III (127)	Surgical treatment (127 patients), adjuvant chemotherapy (110 patients), adjuvant radiotherapy (1 patient)
Jones et al[21]	2015	Retrospective cohort study	118	N/A; males = 61.9%, females = 38.1%	Colon (66 patients) and rectum (52 patients)	I (26), II (47), III (45)	Surgical treatment (118 patients), adjuvant chemotherapy (73 patients)
Kim and Lee[22]	2013	Retrospective cohort study	336	60.4 ± 11.1; males = 60.7%, females = 39.3%	Colon (224 patients) and rectum (112 patients)	II (189 patients) and III (147 patients)	Surgical treatment for all patients
Moloney et al[23]	2019	Retrospective cohort study	138	67; males = 54.3%, females = 45.7%	Colon (90 patients) and rectum (48 patients)	I (58 patients), II (69 patients), III (11 patients)	Surgical treatment for all patients
Nicolini et al[24]	2010	Prospective cohort study	108	60	Colon (69 patients) and rectum (39 patients)	I (29 patients), II (41 patients), and III (38 patients)	Surgical treatment for all patients
Rodrigues et al[25]	2017	Prospective cohort study	404	64.6; males = 59.7%, females = 40.3%	Colon (199 patients) and rectum (205 patients)	II (177 patients) and III (227 patients)	Surgical treatment (404 patients), neoadjuvant chemotherapy in the rectum (175), adjuvant chemotherapy (196 patients) and adjuvant chemotherapy in the colon (86 patients)
Shinkins et al[26]	2017	Randomized controlled trial	582	65; males = 61.3%, females = 38.7%	N/A	I (110 patients), II (282 patients), III (166 patients) and U (24 patients)	Surgical treatment for all patients