Summary

Colorectal cancer (CRC) is a major health concern, ranking as the third most common cancer in the United States. Screening programs, especially colonoscopy, play a crucial role in preventing CRC by removing and detecting polyps or early-stage cancers. Despite inherent risks, colonoscopy's effectiveness in saving lives is significant. In this review, we analyzed the outcomes of screening colonoscopies in an asymptomatic population for 15 years, focusing on detection rates and complications. We compared the data with previous meta-analyzes to evaluate changes in efficacy and safety. We conducted a systematic search of medical literature databases (1 January 2012 to 31 December 2023) for English-language studies on CRC screening colonoscopy. Our inclusion criteria comprised complete articles with over 500 participants with extractable data and a focus on screening colonoscopy outcomes in average-risk populations. In total, 2,897,025 people were screened, most (99.6%) were asymptomatic and were an average-risk population. Colonoscopy was complete and reached the cecum in 97–99% of the procedures. CRC was found in 0.5% (95% confidence interval [95%CI] 0.4–0.7%) of the participants. Advanced adenoma was found in 7.6% (95%CI 6.2–9.3%) of the cases. Complications were rare. Perforation developed in 0.022% of the cases and bleeding in 0.148%. Our findings exhibited a significant increase in the detection yield of adenomas and advanced adenomas with low complication rates, which shows that colonoscopy is feasible and suitable for screening for CRC in asymptomatic people.