Cell-Free Blood DNA Tests Less Effective Than Other CRC Screening

WEDNESDAY, Oct. 30, 2024 (HealthDay News) -- Cell-free DNA blood tests (cf-bDNA) may be more costly and less effective for colorectal cancer (CRC) screening than other screening modalities, according to a study published online Oct. 29 in the Annals of Internal Medicine.

Uri Ladabaum, M.D., from the Stanford University School of Medicine in California, and colleagues estimated the clinical and economic impacts of novel CRC screening tests in a cost-effectiveness analysis using published data for average-risk persons ages 45 to 100 years.

The researchers found that compared with no screening for CRC, the relative rates for CRC incidence were 0.21, 0.29, 0.33, 0.32, 0.58, and 0.58 for colonoscopy every 10 years, annual fecal immunochemical test (FIT), and triennial next-generation multitarget stool DNA, FIT-RNA, cf-bDNA (Guardant Shield), and cf-bDNA (Freenome), respectively; the corresponding relative rates for CRC mortality were 0.19, 0.25, 0.28, 0.28, 0.44, and 0.46. Compared with no screening, the cf-bDNA test (Shield) cost $89,600 per quality-adjusted life-year gained; alternatives were more effective and less costly. In a sensitivity analysis, when novel test intervals were shortened to two or one years, incremental costs exceeded incremental benefits. Assuming equal colonoscopy follow-up, the cf-bDNA test matched FIT's impact on CRC mortality at 1.35-fold that of FIT's uptake rate. CRC deaths increased if persons who accept colonoscopy or stool tests shifted to cf-bDNA.

"The blood tests are certainly much better than nothing, but you'll worsen the population outcomes and raise health care costs if you see people switching from colonoscopies to first-generation blood tests," Ladabaum said in a statement.

Abstract/Full Text (subscription or payment may be required)