The NordICC Study recently published in The New England Journal of Medicine and widely reported on by media outlets has raised questions regarding the benefit of screening colonoscopy in lowering the risk of colorectal cancer and cancer-related deaths among otherwise healthy and symptom-free men and women aged 55 to 64.
Provocative headlines and commentaries have added further to the controversy, with one outlet (CNN) describing colonoscopies as the “dreaded rite of passage for many middle-aged adults. The promise has been that if you endure the awkwardness and invasiveness of having a camera travel the length of your large intestine once every decade after age 45, you have the best chance of catching – and perhaps preventing – colorectal cancer.”
SAGES hopes to clarify the results of the NordICC study and frame them in the context of decade-long efforts by several national agencies to reduce the risk of colorectal cancer, the second leading cause of cancer death in the United States, by promoting early detection and treatment of lesions. The NordICC study enrolled 84,585 patients across Poland, Norway, and Sweden where patients were randomized to either receive a screening invitation (to undergo colonoscopy) or to follow usual care. At a median follow-up of 10 years, the authors found that the risk of developing colorectal cancer was 18% lower in the group invited to undergo screening and the risk of death from colorectal cancer was not significantly lower relative to the usual care group (0.31% vs 0.28%). These results deviate from the results of prior screening trials and fell short of the expected 25% reduction in colorectal cancer-related mortality.
However, these results must be interpreted with caution considering the significant design limitations. Among patients who received an invitation to undergo screening, only 42% complied with the study protocol and underwent colonoscopy. Despite the lower-than-expected compliance with the screening protocol, all patients in the screening arm, including the 58% of patients who did not undergo colonoscopy, were still included in the “invited to undergo screening” group, which significantly diluted the impact of screening colonoscopy on reducing colorectal cancer incidence and cancer-related mortality. In addition, the study did not specify when or how the patients who did not undergo screening colonoscopy underwent subsequent diagnosis of colorectal cancer. Given that there were no significant differences in cancer stage at diagnosis between the groups, colonoscopy presumably played a role in establishing a diagnosis in both groups and impacted cancer-related mortality across the entire cohort of patients.
Ultimately, the most important finding of the NordICC study is that a screening colonoscopy did reduce the risk of colorectal cancer at 10 years. The lower-than-expected benefits, especially as it relates to reducing cancer-related mortality, should not impact national recommendations regarding colorectal cancer screening. At this time, colonoscopy remains the most effective screening test to identify and reduce the incidence of colorectal cancer. Guidelines for screening have been established by the American Cancer Society to begin at age 45 for patients with average risk. Patients with other risk factors such as family history may benefit from earlier screening. Colonoscopy for screening in average risk patients was approved by CMS for Medicare beneficiaries in 2000 and is almost universally covered by most private insurance carriers.
SAGES affirms the value of colonoscopy in the prevention, identification, and treatment of colorectal cancer based on the preponderance of evidence. We urge the public to follow the guidelines for screening to prevent colon cancer. We also advocate for the insurance industry to maintain coverage for screening colonoscopy to ensure equitable access to care and maintain the standard for public health. SAGES represents more than 6,000 surgeons and endoscopists who care for patients with GI diseases including colon cancer. Our members are focused on the use of flexible endoscopy and minimally invasive surgery techniques to achieve the best results for our patients.