ACS updated colorectal cancer screening guidance, reaffirming screening at age 45 and adding newer stool-based and blood-based options.
The American Cancer Society (ACS) has updated its
“We need to increase our emphasis on colorectal cancer as a highly preventable disease as much as a treatable one,” Robert Smith, PhD, senior vice president for early cancer detection science at ACS and senior author of the report, said in the announcement. “By offering more screening tools in our guideline update, more eligible adults will be able to participate in lifesaving colorectal cancer testing, helping to close the screening gap and catch more cancers at an earlier, treatable stage.”1
Key Facts
The update, published in CA: A Cancer Journal for Clinicians, keeps the core ACS age-based framework unchanged: average-risk adults should begin
The main change is expansion of accepted screening modalities. ACS now includes next-generation multitarget stool DNA testing, multitarget stool RNA testing, and a blood-based tumor DNA test. Multitarget stool DNA and RNA tests are recommended every 3 years. The blood-based test is positioned more narrowly: ACS recommends it only for individuals who decline or do not complete preferred screening tests, citing lower sensitivity for advanced precancerous lesions and stage I cancers compared with established stool-based strategies.1
The guideline preserves long-standing options, including annual high-sensitivity guaiac fecal occult blood testing, annual fecal immunochemical testing, multitarget stool DNA testing every 3 years, colonoscopy every 10 years, flexible sigmoidoscopy every 5 years, and computed tomography colonography every 5 years. Consistent with prior guidance, ACS emphasizes that any abnormal stool- or blood-based test must be followed by timely colonoscopy, preferably within 6 months, to complete screening.1
The clinical rationale remains substantial. CRC screening can detect early-stage cancers and precancerous lesions, but ACS notes that more than 20 million eligible US adults remain unscreened, approximately 1 in 3 adults in the eligible population. The organization also cited recent ACS data indicating CRC is now the leading cause of cancer death among adults younger than 50 years, underscoring the importance of screening uptake beginning at age 45 years.1 The US Preventive Services Task Force similarly recommends CRC screening for adults aged 45 to 75 years, reflecting a broader national shift toward earlier screening for average-risk adults.2
Evidence supporting newer molecular approaches varies by test type and target. In the BLUE-C study, a next-generation multitarget stool DNA test demonstrated 93.9% sensitivity for CRC and 43.4% sensitivity for advanced precancerous lesions, with specificity of 90.6% for advanced neoplasia.3 For blood-based screening, the ECLIPSE study of a cell-free DNA assay reported 83.1% sensitivity for CRC, 89.6% specificity for advanced neoplasia, and 13.2% sensitivity for advanced adenomas.4 These performance differences help explain why ACS places blood-based testing as an alternative for patients who otherwise would not complete recommended screening, rather than as a preferred first-line option.
For clinicians, the update reinforces shared decision-making centered on completion. Colonoscopy remains the definitive diagnostic follow-up test and a major screening option because it allows detection and removal of premalignant lesions. However, home-based stool testing may reduce logistical barriers for patients who face transportation limitations, procedural concerns, or limited access to endoscopy. Blood-based testing may further expand reach in office-based settings, but its lower detection of advanced precancerous lesions raises questions about long-term effect on CRC incidence reduction.
Implementation will be the key next step. ACS stated that ongoing evaluation of adherence, real-world uptake, and clinical outcomes will inform future updates for targeted screening tests.1 In practice, clinicians may need to balance test availability, insurance coverage, patient preference, local colonoscopy capacity, and the ability to ensure prompt follow-up after positive noninvasive results.
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