Colorectal cancer is a major global health concern, with 1.9 million new cases and 935,000 deaths annually. Early detection and interception is the best way to reduce these alarming numbers. Population-based screening with FIT is the most widely used approach for this purpose. After a positive FIT result, polyps are removed in more than 60% of screened individuals, who then undergo regular surveillance colonoscopies to monitor for cancer or precancerous growths.
Over the last decade, stool tests have been widely implemented for colorectal screening, but their use for surveillance after polypectomy has hardly been investigated. This observational study aimed to evaluate whether three stool tests—the multitarget stool DNA (mt-sDNA) test and two types of FITs—could serve as safe alternatives to colonoscopy in this context. The study included 3,830 participants aged 50-75 who were scheduled for colonoscopy surveillance at 18 endoscopy centers across the Netherlands. The stool samples provided by the before their colonoscopy were analyzed for their ability to detect advanced neoplasia, i.e. colorectal cancer, or its advanced precursors, often larger polyps. Using mathematical modeling, each test’s accuracy was used to predict long-term efficacy and colonoscopy burden of a range of surveillance scenarios.
Possible scenarios were found for all three tests in which the achieved efficacy was equal to colonoscopy surveillance, demonstrating that stool tests may be a safe alternative for colonoscopy in surveillance. The highest reduction in the number of necessary colonoscopies (41%) and the highest cost-effectiveness were achieved with annual FIT surveillance. This scenario both reduces patient burden and health care cost. “Our findings suggest that stool-based tests, particularly FIT, could significantly reduce unnecessary colonoscopies, easing the strain on healthcare systems while still effectively detecting high-risk cases”, says Gerrit Meijer, Principal Investigator at the Netherlands Cancer Institute. “This could lead to new guidelines that better balance cancer surveillance with patient comfort and healthcare costs”.
Next step
To confirm these findings, the researchers plan to evaluate the effectiveness of annual FIT monitoring after polyp removal in practice. This could pave the way for a new, less invasive form of follow-up care, where people undergo colonoscopy only if they are truly at high risk for colorectal polyps or cancer.
This research was financially supported by Alpe d’Huzes and KWF Dutch Cancer Society