EXTENDING the colonoscopy screening interval from 10 to 15 years in individuals without family history of colorectal cancer (CRC) after initial negative findings could be safe, says a study conducted on 110,074 individuals by Qunfeng Liang, German Cancer Research Centre and Heidelberg University, Germany, and colleagues. This may only marginally increase the risk, missing two CRC cases and one CRC-related death per 1,000 individuals.
Using Swedish nationwide register-based data, this cohort study examined CRC diagnoses and CRC-specific mortality among individuals without a family history of CRC. The exposed group underwent their first negative CRC colonoscopy findings at ages 45–69 years between 1990–2016. Controls included those matched by sex, birth year, and baseline age; those who did not undergo colonoscopy; or had CRC diagnosis post-colonoscopy. Up to 18 controls were matched per exposed individual. Follow-up spanned 1990–2018, analysed from November 2022–November 2023.
The study defined a first colonoscopy without colorectal polyp, adenoma, carcinoma in situ, or CRC within 6 months, as negative for CRC. Standardised ratios compared risks in exposed and control groups.
The study comprised 110,074 individuals (59.2% females) in the exposed group and 1,981,332 (59.2% females) in the control group, with a median age of 59 years in both groups. Over up to 29 years, 484 incident CRCs and 112 CRC-specific deaths occurred after the first negative CRC colonoscopy findings. For 15 years, the exposed group had significantly lower CRC and CRC-specific death risks than their matched controls. At 15 years post-negative CRC colonoscopy, the 10-year standardised incidence ratio was 0.72 (95% confidence interval: 0.54–0.94), and the standardised mortality ratio was 0.55 (95% confidence interval: 0.29–0.94), indicating a 28% lower CRC risk in the exposed group. Extending the screening interval to 15 years could miss only two CRC cases and one CRC-specific death per 1,000 individuals, potentially sparing 1,000 colonoscopies.
The research discovered that extending the time between colonoscopy screenings from 10 to 15 years for those without a family history of CRC and initial negative colonoscopy findings could be beneficial. This longer interval could help avoid unnecessary invasive procedures.
Reference
Liang Q et al. Longer interval between first colonoscopy with negative findings for colorectal cancer and repeat colonoscopy. JAMA Oncol. 2024;DOI:10.1001/jamaoncol.2024.0827.
