CA Cancer J Clin
New colorectal screening guidance expands at-home options, sidelines blood tests
Clinical Takeaway: The American Cancer Society (ACS) continues to recommend colorectal cancer screening beginning at age 45 for average-risk adults, but the 2026 update expands preferred stool-based options to include multitarget stool RNA (mt-sRNA) testing every 3 years. Blood-based screening tests are not considered preferred because of lower sensitivity for advanced precancerous lesions and early-stage cancers; they should be offered only to patients who decline or do not complete recommended stool-based or visual screening tests.
In its first colorectal cancer (CRC) screening update since 2018, the ACS reaffirmed that adults at average risk should start screening at age 45 and continue through age 75 if life expectancy exceeds 10 years. The updated guideline also stresses that “the most effective screening test is the one that the patient completes.”
The biggest change is the addition of the FDA-approved multitarget stool RNA test (ColoSense) as a preferred stool-based option alongside FIT, high-sensitivity guaiac fecal occult blood testing, and multitarget stool DNA testing. The mt-sRNA assay, recommended every 3 years, showed 94.4% sensitivity for CRC and 45.9% sensitivity for advanced adenomas in a large validation study, outperforming FIT alone for cancer detection.
The guideline also reviewed emerging blood-based screening tests, including Guardant Shield and Freenome SimpleScreen. Although these assays may improve participation among patients reluctant to use stool-based tests or undergo colonoscopy, the ACS stopped short of endorsing them as preferred options. Sensitivity for advanced precancerous lesions was only about 13% in major validation studies, and sensitivity for stage I cancers lagged behind later-stage disease.
“We always say the best test is the one you get,” said Robert Smith, PhD, senior vice president of early cancer detection science at the ACS, underscoring the guideline’s emphasis on expanding screening participation through additional testing choices.
Still, the authors emphasized that “blood-based screening tests are not preferred screening options at this time,” recommending their use only for individuals who “decline or have not completed preferred screening tests.”
The ACS also emphasized that any positive noncolonoscopy screening test — including stool-based and blood-based assays — must be followed by timely colonoscopy, ideally within 6 months.
The update comes amid rising CRC incidence in younger adults. CRC is now the leading cause of cancer death in men younger than 50 years and the second leading cause in women younger than 50 years, according to the guideline.
Source: Wolf AMD, et al. (2026, May 27). CA Cancer J Clin. Colorectal cancer screening: An update to the American Cancer Society guideline, 2026