“Screening colonoscopy has been shown to reduce colorectal cancer (CRC) incidence and mortality by enabling detection and removal of precancerous lesions. However, the available evidence about the optimal screening interval is limited. [..]
More targeted screening offers would potentially reduce the burden of testing and demand of capacities and costs associated with colonoscopy, thereby also counteracting the frequently reported overuse and underuse of screening examinations in considerable proportions of the population. [..]
Anonymized registration of screening colonoscopy findings and the use of the anonymized data for program evaluation by the Central Research Institute of Ambulatory Health Care in Germany is mandatory in the German screening colonoscopy program. [..] In Germany, certification for conducting screening colonoscopies is tightly regulated based on extensive previous training and experience, and its maintenance is subject to rigorous quality control. Specifically, only gastroenterologists, internists, or surgeons who have conducted at least 200 colonoscopies during the preceding 2 years will be certified. Maintenance of certification is contingent on conducting at least 200 colonoscopies per year, the quality and completeness of which needs to be proven by photo or video documentation. [..]
Among repeated screening colonoscopy users, prevalence gradually increased with time intervals since negative index colonoscopy (from 5.2% to 6.6% in men and 3.6% to 4.9% in women for intervals of 10, 11, 12, 13, and ≥14 years). Even the prevalence 14 years or greater after a negative screening colonoscopy was markedly lower than those in all screening colonoscopy users, for whom ADNs [advanced adenoma or cancer] were found in 65 911 men (11.6%) and 49 100 women (7.1%). [..]
Consistent with findings for all screening colonoscopies, the prevalence of ADN was substantially (approximately 40%) higher in men vs women using a repeated screening colonoscopy regardless of the interval between examinations. Among women younger than 75 years at repeated screening, prevalence of ADN was very low (approximately 4%, including <0.5% cancers) even at intervals of up to 13 years, and only slightly higher (4%-6%) at intervals 14 years or greater. [..]
The study findings also suggest that age may be more strongly associated with higher prevalence at repeated screening than the interval between examinations. Within the same sex, prevalence of advanced findings in those aged 65 to 74 years with intervals of 13 years or longer was on the same level and partly even lower than those seen in individuals 75 years or older with 10-year intervals. This may not be unexpected, as older age is generally a risk factor for CRC. However, it has largely been unknown whether and to what extent these well-described increases in CRC risks along an age trajectory would also manifest in those free of polyps at an index colonoscopy, and the limited previous evidence in this respect has been inconclusive.
Taken together, the strong and consistent differences between men and women, as well as the lower prevalence among younger vs older repeated screening participants, indicates the potential use of risk stratification by sex and age in defining screening colonoscopy intervals. For instance, women at younger screening ages with no finding at an index colonoscopy could possibly be screened at prolonged intervals or, alternatively, be offered less invasive methods, such as stool tests, while maintaining the 10-year interval for men and women at older ages. By reducing the burden of testing in those at lower risk, such risk-adapted intervals could promote a more efficient use of colonoscopy capacities and resources regardless of a country’s income level. Future studies should assess the potential implications of risk-adapted intervals from a health-economic point of view. Possibly, cost-effectiveness analyses on CRC screening may need to be carefully revised to reflect that participants free of polyps at an index colonoscopy have a long-lasting lower risk of advanced colorectal neoplasia.
[..] this study specifically focuses on asymptomatic individuals at average risk of CRC with negative index screening colonoscopy who opted to undergo a repeated screening colonoscopy 10 or more years later. Therefore, broader generalizing of this study’s findings, which do not extend to individuals who might need to undergo a colonoscopy for clarification of symptoms (eg, rectal bleeding) at earlier intervals or individuals at higher risk of CRC (eg, inflammatory bowel disease), should be done cautiously.”
Full article, T Heisser, J Kretschmann B Hagen, JAMA Internal Medicine, 2023.1.17