Colonoscopy Screening Reduced Colorectal Cancer Incidence but No Significant Mortality Benefit

A 13-year follow-up of a randomized controlled trial found that a single colonoscopy screening significantly reduced colorectal cancer incidence but did not significantly lower mortality. In this multicountry study involving 84,583 adults aged 55–64 years from Norway, Poland, and Sweden, participants were randomized to receive colonoscopy screening or no screening. After 13 years, colorectal cancer incidence was lower in the screening group (1.46%) compared to the no-screening group (1.80%), with a risk reduction of 19% in intention-to-screen analyses and 45% in per-protocol analyses. The reduction was more pronounced for distal colorectal cancer and in men, while the effect on proximal cancer and in women was less evident. Although colorectal cancer mortality was slightly lower in the screening group (0.41% vs 0.47%), the difference was not statistically significant. Notably, overall mortality rates were lower than initially expected in both groups, which may have influenced the findings. Source: https://www.thelancet.com/