New paper shows (perhaps counter-intuitively…) that more frequent colonoscopy in #LynchSyndrome does not reduce CRC incidence… however
Background: People with Lynch syndrome have a high risk of colorectal cancer, and regular colonoscopies are recommended to prevent or detect cancer early. However, the evidence supporting these recommendations has been mixed.
Study Goal: Researchers used data from 4,732 patients in the English NHS with Lynch syndrome to see how well they followed surveillance guidelines and what impact colonoscopies had on their risk of developing or dying from colorectal cancer.
Key Findings:
- Patients who had colonoscopies at intervals of three years or less showed a decrease in deaths specifically from colorectal cancer and from all causes combined. However, there was no change in the overall number of new colorectal cancer cases.
- Interestingly, patients undergoing colonoscopies at intervals of two years or less showed an increase in the total number of colorectal cancer cases, particularly early-stage ones. This might be due to detecting more cancers that wouldn’t have caused problems (overdiagnosis) or the short study period.
- The study noted that while reduced mortality was observed, it’s difficult to definitively attribute this solely to surveillance due to the observational nature of the study, which means other factors (selection bias) could be at play.
Conclusion: The benefits of surveillance colonoscopy for Lynch syndrome patients are still not fully clear. While regular checks might reduce mortality, the impact on cancer incidence is complex and might even lead to overdiagnosis with very frequent screening. The authors suggest that more rigorous studies, like randomized controlled trials, are needed to fully understand the effectiveness of this intervention.does reduce overall mortality.
https://gut.bmj.com/content/early/2026/08/06/gutjnl-2025-337379
Lynch Syndrome Ireland 