Risk-Adapted Screening for CRC Comparable to Established Strategies

A personalized risk-adapted screening approach that prioritizes colonoscopy for those at high risk for colorectal cancer (CRC) was effective and affordable, a randomized trial in China showed.

Among over 19,000 participants, detection rates for advanced neoplasia were similar for those who underwent one-time colonoscopy (2.76%), annual fecal immunochemical testing (FIT; 2.17%), or risk-adapted screening (2.35%) over a 3-year period, reported Min Dai, PhD, of Peking Union Medical College Hospital in Beijing, and colleagues.

Moreover, costs for detecting one advanced neoplasm were comparable at $1,004, $844, and $970, respectively, they noted in Clinical Gastroenterology and Hepatology.

“This large-scale randomized controlled trial demonstrated that the proposed risk-adapted approach is a feasible, effective and cost-favorable personalized CRC screening strategy compared with established colonoscopy and FIT strategies, which could be adopted as a promising approach in future population-based CRC screening programs, especially in constrained healthcare resource settings,” Dai and team wrote.

Not surprisingly, colonoscopy led to the highest detection rate for any neoplasm (10.3%), followed by risk-adapted screening (6.9%) and FIT (5.6%), they said.

“I’m not entirely sure if it would change clinical practice at the moment, at least in the U.S.,” Allen Kamrava, MD, of Cedars-Sinai Medical Center in Los Angeles, told MedPage Today.

“A more compelling analysis would be to have the screening randomized within the same patients. That is, for a patient that is given an FIT test to then be randomized and blinded to an endoscopist to perform a colonoscopy,” noted Kamrava, who was not involved in this study. “This would show on the same patient if the FIT test or the colonoscopy is more sensitive.”

CRC is the second most common cause of cancer deaths worldwide, Dai’s group noted. Current guidelines incorporate a “one-size-fits-all” age-based approach recommending colonoscopy every 10 years and FIT annually or every other year. However, this strategy does come with drawbacks, such as low adherence, which can be attributed to barriers to or disparities in screening.

For this multicenter study, Dai and colleagues enrolled 19,373 participants and randomized 3,883 to one-time colonoscopy, 7,793 to annual FIT, and 7,697 to annual risk-adapted screening, based on a risk assessment stratification score. Those at high risk for CRC — as evidenced by a modified Asia-Pacific Colorectal Screening (APCS) score of ≥4 — were referred to colonoscopy, and those at low risk (APCS <4) were referred to FIT from May 2018 to May 2021.

Among the participants, mean age was 60.5, and 58.3% were women. Although baseline characteristics were similar among the groups, more risk-adapted participants had a family history of CRC. Some (n=349) underwent CRC screening without adhering to the trial protocol.

The participation rates for baseline screening among the colonoscopy, FIT, and risk-adapted screening groups were 42.3%, 94%, and 85.2%, respectively, and these rates increased to 42.4%, 99.3%, and 89.2% after three screening rounds.

Across all groups, participation decreased with increasing age. No differences between men and women were observed among the colonoscopy and FIT groups, but more women participated in risk-adapted screening (97% vs 78%).

None of the screening strategies reached significance after adjusting for sex, age, and study center:

• Colonoscopy versus FIT: OR 1.27, 95% CI 0.99-1.63
• Colonoscopy versus risk-adapted screening: OR 1.17, 95% CI 0.91-1.49
• Risk-adapted screening versus FIT: OR 1.09, 95% CI 0.88-1.35

Compared with risk-adapted screening, colonoscopy had a higher detection rate for advanced neoplasia in the proximal colon and among women.

The number of colonoscopies needed to detect one advanced neoplasm was 15.4, but fewer colonoscopies were needed after risk-adapted screening (10.2) or FIT (7.8).

Dai and team acknowledged that long-term CRC mortality rates were not assessed, and colonoscopy rates among FIT-positive patients were not optimal, which were limitations to their study.