Prioritizing Blood-Based CRC Tests May Lead to Higher Costs and Worse Outcomes, Study Finds

In a federally qualified health care setting, prioritizing blood-based colorectal cancer (CRC) screening over existing stool-based tests may result in increased costs and poorer outcomes, according to a new study published in JAMA Network Open.1

Findings from the validated microsimulation model suggest that novel screening methods should be carefully evaluated before being widely implemented in community settings.1

“This simulation study examines the benefits, costs, and cost-effectiveness of noninvasive screening tests when adherence to this multistep screening process reflects adherence rates in populations receiving care at FQHCs [Federally Qualified Health Centers],” Carolyn Rutter, PhD, a professor with the Hutchinson Institute for Cancer Outcomes Research and the Biostatistics Program within the Public Health Sciences Division at Fred Hutch Cancer Center, and colleagues wrote.1 “Stool-based tests were a cost-effective screening approach, even with low adherence to both noninvasive screening and follow-up colonoscopy.”

Currently, there are 2 FDA-approved blood-based tests for CRC screening in people at average risk: Shield and Epi proColon.2 These tests detect possible signs of CRC or pre-cancerous polyps in the blood. Stool-based tests, which are typically completed at home, require more frequent testing, and an abnormal result necessitates a follow-up colonoscopy.

The study utilized a validated microsimulation model to project CRC screening outcomes for a simulated cohort of 10 million individuals aged 50 in 2025. This cohort represented a predominantly Hispanic or Latino population characteristic of patients served by FQHCs in Southern California. The simulated population exhibited low adherence rates: 45% for first-step noninvasive testing, 40% for follow-up colonoscopy after an abnormal result, and 80% for ongoing surveillance colonoscopy.1

The screening strategies modeled included no screening, annual or biennial fecal immunochemical test (FIT), triennial multitarget stool DNA (mt-sDNA) testing, and triennial blood-based testing. Researchers assumed that blood-based tests would increase first-step adherence by 17.5%.1

The primary outcomes assessed included CRC incidence and mortality, life-years gained (LYG) and quality-adjusted life-years (QALYs) gained relative to no screening, costs, and net monetary benefit, assuming a willingness to pay $100 000 per QALY gained.1

Under realistic adherence assumptions, annual FIT emerged as the most effective and cost-effective screening strategy, yielding 121 LYG per 1000 screened individuals and a net monetary benefit of $5883 per person. Triennial blood-based screening, in contrast, was the least effective, providing only 23 LYG per 1000 and failing to meet cost-effectiveness thresholds due to negative net monetary benefit.1

Even in scenarios with perfect adherence, triennial blood testing (77 LYG per 1000 individuals) was outperformed by annual FIT with realistic adherence (88 LYG per 1000 individuals), demonstrating FIT’s superior balance of effectiveness and cost-efficiency in community health settings.1

Rutter and colleagues acknowledged several limitations. First, adherence rates were based on observed FQHC data, allowing for variability in missed screenings while assuming a single level of adherence over time. Second, while CRC screenings entail short-term costs and long-term benefits, many individuals transition out of the FQHC system upon reaching Medicare eligibility, which may improve adherence with more consistent insurance coverage.1

Despite these limitations, the findings suggest that annual FIT may be the most effective and cost-efficient noninvasive screening option for CRC.1

“Setting health policy based on increasing adherence to noninvasive screening, without considering effectiveness and adherence to follow-up colonoscopy, could waste health care resources and result in inferior patient outcomes,” the investigators concluded.1

References:

1. Nascimento de Lima P, Matrajt L, Coronado G, et al. Cost-effectiveness of noninvasive colorectal cancer screening in community clinics. JAMA Netw Open. Published online January 16, 2025. doi:10.1001/jamanetworkopen.2024.54938

2. Colorectal cancer screening tests. American Cancer Society. Accessed January 16, 2025. https://www.cancer.org/cancer/types/colon-rectal-cancer/detection-diagnosis-staging/screening-tests-used.html.