Blood Tests in the New Colorectal Cancer Screening Guideline

The American Cancer Society updated its colorectal cancer screening guideline in 2026, for the first time including a blood-based screening test that detects cell-free DNA. The guideline states explicitly that blood-based tests are NOT a preferred option — they should be offered only to people who decline or have not completed a preferred screening test, because of lower sensitivity for advanced precancerous lesions and stage I cancer and uncertainty about the optimal screening interval. The recommendation to begin screening at age 45 in average-risk adults is unchanged.