ImportanceSeveral noninvasive tests for colorectal cancer screening are available, but their effectiveness in settings with low adherence to screening and follow-up colonoscopy is not well documented.ObjectiveTo assess the cost-effectiveness of and outcomes associated with noninvasive colorectal cancer screening strategies, including new blood-based tests, in a population with low adherence to screening and ongoing surveillance colonoscopy.Design, Setting, and ParticipantsThe validated microsimulation model used for the decision analytical modeling study projected screening outcomes from 2025 to 2124 for a simulated cohort of 10 million individuals aged 50 years in 2025 and representative of a predominantly Hispanic or Latino patient population served by a Federally Qualified Health Center in Southern California. The simulated population had low adherence to first-step noninvasive testing (45%), second-step follow-up colonoscopy after an abnormal noninvasive test result (40%), and ongoing surveillance colonoscopy among patients with high-risk findings at follow-up colonoscopy (80%).ExposuresColorectal cancer screening strategies included no screening, an annual or biennial fecal immunochemical test, a triennial multitarget stool DNA test, and a triennial blood-based test. Using a blood-based test was assumed to increase first-step adherence by 17.5 percentage points.Main Outcomes and MeasuresOutcomes included colorectal cancer incidence and mortality, life-years gained and quality-adjusted life-years gained relative to no screening, costs, and net monetary benefit assuming a willingness to pay of $100 000 per quality-adjusted life-year gained.ResultsUnder realistic adherence assumptions, a program of annual fecal immunochemical testing was the most effective and cost-effective strategy, yielding 121 life-years gained per 1000 screened individuals and a net monetary benefit of $5883 per person. Triennial blood testing was the least effective, yielding 23 life-years gained per 1000, and was not cost-effective, with a negative net monetary benefit. Annual fecal immunochemical testing with 45% first-step adherence and 80% adherence to follow-up and surveillance colonoscopy yielded greater benefit than triennial blood testing with perfect adherence (88 vs 77 life-years gained per 1000).Conclusions and RelevanceThis study suggests that in a federally qualified health care setting, prioritizing the convenience of blood tests over less costly and more effective existing stool-based tests could result in higher costs and worse population-level outcomes. Novel screening modalities should be carefully evaluated for performance in community settings before widespread adoption.
Read full abstract