Patient vs Population Level Colorectal Cancer Screening Outcomes Compared

Screening colonoscopies have shown clear benefit at the patient level, but the overall efficacy of screening as a primary population-based screening modality is still ambiguous.

Colonoscopy screening programs for colorectal cancer (CRC) have clear benefits on the patient level, but the effect of colonoscopy-based CRC screening programs on a population level remain unclear, according to a reaction letter published in Gastroenterology.

The letter referred to results from a study published in The New England Journal of Medicine, in which individuals living in 4 countries in Europe between 2009 and 2014 were randomly assigned 1:2 to be invited to undergo colonoscopy screening or not. The patients were aged 55 to 64 years and were screening- and fecal immunochemical testing (FIT)-naïve.

The study reported that 42.0% of the invited participants underwent colonoscopy and the resulting adenoma detection rate was 30.7%.

Overall, the screening program significantly reduced 10-year incidence of CRC (risk ratio [RR], 0.82; 95% CI, 0.70-0.93) but not CRC-related mortality (RR, 0.90; 95% CI, 0.64-1.16) in the intention-to-treat analysis. In the per-protocol analysis, however, the screening program significantly reduced both 10-year incidence of CRC (RR, 0.69; 95% CI, 0.55-0.83) and CRC-related mortality (RR, 0.50; 95% CI, 0.27-0.77).

Regardless of the modalities employed, ongoing efforts should be made to provide widespread patient education on CRC screening to improve uptake and optimize health equity.

These results have been a subject of debate. Some experts believe that per-protocol results are more representative of the benefits of colonoscopy programs, while others have pointed out that barriers to acceptability and uptake of such programs are relevant, making the intention-to-treat results more realistic.

 “Similar studies with long(er) follow-up periods, studies comparing colonoscopy and FIT for population screening, and studies carried out in different populations are all needed,” the author concluded. Regardless of the modalities employed, ongoing efforts should be made to provide widespread patient education on CRC screening to improve uptake and optimize health equity.”

Disclosure: The author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of the author’s disclosures.

References:

Forbes N. Outcomes associated with colorectal cancer following population-based colonoscopy screening: Results from a European pragmatic randomized trial. Gastroenterology. Published online November 12, 2022. doi:10.1053/j.gastro.2022.10.038