INDIVIDUALS without a family history of colorectal cancer (CRC) could safely extend their colonoscopy screenings from the standard 10-year interval to 15 years, according to recent research. This potential change aims to reduce unnecessary invasive procedures while maintaining effective CRC prevention.
The study, conducted using nationwide Swedish register-based data, examined CRC diagnoses and CRC-specific mortality among individuals aged 45–69 years who had a first colonoscopy between 1990–2016 that showed no signs of CRC. The exposed group consisted of 110,074 individuals (59.2% female) with a median age of 59 years, while the control group included 1,981,332 individuals (59.2% female) matched by sex, birth year, and baseline age. Up to 18 controls were matched with each exposed individual, encompassing those who either did not undergo a colonoscopy during follow-up or received a CRC diagnosis from their procedure.
Over a follow-up period extending up to 29 years, the study tracked 484 incident CRC cases and 112 CRC-specific deaths in the exposed group. The findings revealed that, for up to 15 years after a negative first colonoscopy, the risks of developing CRC and dying from it were significantly lower in the exposed group compared to controls. Specifically, 15 years post-screening, the 10-year standardised incidence ratio was 0.72 (95% CI: 0.54–0.94), and the 10-year standardised mortality ratio was 0.55 (95% CI: 0.29–0.94). This means the 10-year cumulative risk of CRC in the 15th year was only 72% of that in the control group, and the risk of CRC-specific death was reduced by 45%.
Moreover, extending the screening interval to 15 years could potentially miss the early detection of only two CRC cases and prevent one CRC-specific death per 1,000 individuals. In contrast, it could also avoid approximately 1,000 colonoscopies, reducing the burden of invasive procedures on patients and healthcare systems.
Researchers conclude that for those without a family history of CRC, extending the colonoscopy screening interval from 10 to 15 years after a negative first colonoscopy is a viable option. This adjustment could help minimise unnecessary examinations while still effectively lowering CRC incidence and mortality rates.
The study highlights the importance of personalised screening strategies and suggests that longer intervals may be appropriate for low-risk populations, potentially reshaping current CRC screening guidelines.
Reference
Liang Q et al. Longer interval between first colonoscopy with negative findings for colorectal cancer and repeat colonoscopy. JAMA Oncol. 2024;10(7):866-873.
