Effects of sigmoidoscopy screening (including colonoscopy) on colorectal cancer: A meta-analysis based on randomized controlled trials

Abstract

Background: This study aimed to investigate the role of endoscopy screening in colorectal cancer (CRC). Methods: Up to January 2023, databases were searched for studies related to sigmoidoscopy and colonoscopy screening. The incidence of CRC, and/or CRC mortality were the main observation outcomes. Results: A total of 5 randomized controlled trials (RCTs) published from 2017 to 2022 were included. Among them, four studies used sigmoidoscopy screening and one study involved colonoscopy screening. Statistical results showed that the incidence (RR: 0.78, p < 0.001) and mortality (RR: 0.75, p < 0.001) of CRC were significantly lower in the screening group than in the control group. Further, a subgroup analysis of CRC site indicated that the incidence and mortality of CRC in the screening group were significantly lower than those in the non-screened group, regardless of distal CRC (Incidence: RR: 0.66, p < 0.001; Mortality: RR: 0.62, p < 0.001) or proximal CRC (Incidence: RR: 0.94, p = 0.038; Mortality: RR: 0.89, p = 0.038). In terms of gender, compared with the non-screening group, both males (Incidence: RR: 0.73, p < 0.001; Mortality: RR: 0.68, p < 0.001) and females (Incidence: RR: 0.85, p < 0.001; Mortality: RR: 0.85, p = 0.017), the screening group had a significant decrease in the incidence and mortality of CRC. Conclusion: This meta-analysis demonstrated that sigmoidoscopy screening (including colonoscopy) could effectively reduce the incidence and mortality of CRC.

Keywords

• Sigmoidoscopy
• Colonoscopy
• Colorectal Cancer
• Incidence
• Mortality
• Meta-Analysis