Article type
Abstract
Background: Blood bilirubin has been widely researched as an emerging possible biomarker of colorectal cancer (CRC) in recent years, but the results of these studies are controversial. We performed a systematic review and meta-analysis to explore the association between blood bilirubin and risk of CRC to resolve the controversy.
Methods: Four databases (PubMed, EMBASE, Web of Science and the Cochrane Library) were used to identify the articles with a date of search of February 12, 2023. Prospective and retrospective studies with full-text that examined the association between blood bilirubin and CRC were included irrespective of language and date of publication. Screening and data extraction were carried out by two independent researchers. Stata 15.0 software was employed to data analysis.
Results: Twelve articles involving 13 studies (4 prospective and 9 retrospective studies) were included for analysis. The result of this study showed that there was no association between bilirubin and the risk of CRC (OR=0.85, 95% CI 0.52-1.39), and no sex-specific (ORmen=1.02, 95% CI 0.93-1.13; ORwomen=0.97, 95% CI 0.88-1.07). Subgroup analysis of studies with CRC site (colon: OR=0.95, 95% CI 0.85-1.07; rectal: OR=0.97, 95% CI 0.91-1.03), study design (prospective studies: OR=0.95, 95% CI 0.85-1.07; retrospective studies: OR=0.79, 95% CI 0.43-1.45), study location (Europe OR=0.98, 95% CI 0.95-1.01; North America: OR=0.75, 95% CI 0.24-2.28; Asia: OR=0.67, 95% CI 0.34-1.35), exposure (serum: OR=0.75, 95% CI 0.41-1.38; plasma: OR=1.08, 95% CI 0.97-1.21), effect size (OR: OR=0.86, 95% CI 0.47-1.56; HR: HR=0.90, 95% CI 0.78-1.04), exclusion criteria (patients with abnormal liver function were excluded: OR=1.04, 95% CI 0.94-1.15; patients with abnormal liver function were not excluded: OR=0.86, 95% CI 0.49-1.52) also showed no correlation. Additionally, on the basis of the above subgroup factors, the gender differences were further analyzed and did not find any correlation (P＞0.05).
Conclusions: The available studies do not support any association between blood bilirubin and risk of CRC. Prospective studies with large sample size are needed to establish the role of bilirubin in the prevention of CRC.
Methods: Four databases (PubMed, EMBASE, Web of Science and the Cochrane Library) were used to identify the articles with a date of search of February 12, 2023. Prospective and retrospective studies with full-text that examined the association between blood bilirubin and CRC were included irrespective of language and date of publication. Screening and data extraction were carried out by two independent researchers. Stata 15.0 software was employed to data analysis.
Results: Twelve articles involving 13 studies (4 prospective and 9 retrospective studies) were included for analysis. The result of this study showed that there was no association between bilirubin and the risk of CRC (OR=0.85, 95% CI 0.52-1.39), and no sex-specific (ORmen=1.02, 95% CI 0.93-1.13; ORwomen=0.97, 95% CI 0.88-1.07). Subgroup analysis of studies with CRC site (colon: OR=0.95, 95% CI 0.85-1.07; rectal: OR=0.97, 95% CI 0.91-1.03), study design (prospective studies: OR=0.95, 95% CI 0.85-1.07; retrospective studies: OR=0.79, 95% CI 0.43-1.45), study location (Europe OR=0.98, 95% CI 0.95-1.01; North America: OR=0.75, 95% CI 0.24-2.28; Asia: OR=0.67, 95% CI 0.34-1.35), exposure (serum: OR=0.75, 95% CI 0.41-1.38; plasma: OR=1.08, 95% CI 0.97-1.21), effect size (OR: OR=0.86, 95% CI 0.47-1.56; HR: HR=0.90, 95% CI 0.78-1.04), exclusion criteria (patients with abnormal liver function were excluded: OR=1.04, 95% CI 0.94-1.15; patients with abnormal liver function were not excluded: OR=0.86, 95% CI 0.49-1.52) also showed no correlation. Additionally, on the basis of the above subgroup factors, the gender differences were further analyzed and did not find any correlation (P＞0.05).
Conclusions: The available studies do not support any association between blood bilirubin and risk of CRC. Prospective studies with large sample size are needed to establish the role of bilirubin in the prevention of CRC.