Clinical Trial Reconsiders the Effectiveness of Colonoscopies

Colonoscopies have long been a recommended preventive care measure for adults aged 45–75; however, a new study found that they are less beneficial than previously thought. The Nordic-European Initiative on Colorectal Cancer (NordICC) trial found that colonoscopy reduced the risk of colorectal cancer over 10 years by 18% but had no significant reduction in the risk of death from colorectal cancer. 

The study compared these results to several randomized sigmoidoscopy trials and found that by using the less invasive screening method, researchers showed an improved 22% reduction in colorectal cancer and a 26% reduction in colorectal cancer-related deaths.  

The NordICC trial used a practice called “consent after randomization” that sorted participants into randomized groups before they had consented to screening. The objective of this practice is to estimate what proportion of people would willingly participate in a colonoscopy, and it is supposed to replicate the actual effectiveness of a treatment as it would occur in a standard care setting. In short, the negative results produced in the NordICC trial also portray the fact that people are less willing to undergo a colonoscopy, thus making it a less effective preventive screening tool.   

In the adjusted per-protocol analysis of the NordICC trial, colonoscopies faired much better, reducing cancer incidence by 31% and cancer-related death by 50%. These results represent a colonoscopy’s efficacy in a population willing to have the procedure performed. Still, they do not demonstrate the procedure’s effectiveness in an everyday setting where patients could choose not to receive a colonoscopy.  

In an editorial published alongside the study, unaffiliated researchers Jason Dominitz, MD, and Douglas Robertson, MD, recommended that patients not forgo colonoscopies when they are recommended. However, the editorial’s authors suggested that clinicians consider offering less-invasive preventive care strategies like sigmoidoscopy and fecal occult blood testing, which effectively detect cancer.  

They expanded, writing: “If the trial truly represents the real-world performance of population-based screening colonoscopy, it might be hard to justify the risk and expense of this form of screening when simpler, less-invasive strategies (e.g., sigmoidoscopy and FIT) are available. However, with increased levels of participation in screening and with high-quality examinations, greater reductions in the incidence of colorectal cancer and related death would be expected.” 

Colonoscopy is certainly in no danger of going away in the United States, and many organizations are investing resources into improving access and effectiveness of screening for their patients. Hospitals and health systems are now using cutting-edge technology like artificial intelligence to improve early detection capabilities while providing an equitable distribution of service to make sure no patient is barred from the opportunity to receive a colonoscopy.