The American Cancer Society released updated colorectal cancer screening guidelines that add blood-based tests and new at-home stool tests to the screening arsenal, making it easier for people to get tested without a colonoscopy. The changes reflect advances in disease detection and a critical shift in public health strategy to expand screening options and lower barriers to access, particularly for the estimated 20 million Americans eligible for screening who have not been tested as recommended.

Why Are New Screening Options Being Added?

Colorectal cancer screening dramatically improves survival rates, with early-stage detection yielding five-year survival rates of more than 90% in the United States. Despite these benefits, about 1 in 3 adults who should be screened have not completed testing. The situation is becoming more urgent because recent research shows colorectal cancer is now the top cancer killer of adults under age 50.

The American Cancer Society's updated guidelines, published in CA: A Cancer Journal for Clinicians, emphasize that the most effective screening test is the one that patients actually complete. By offering more options, the organization hopes to close the screening gap and catch more cancers at an earlier, treatable stage.

"We need to increase our emphasis on colorectal cancer as a highly preventable disease as much as a treatable one. 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," said Dr. Robert Smith, senior vice president of early cancer detection science at the American Cancer Society.

Dr. Robert Smith, Senior Vice President, Early Cancer Detection Science at the American Cancer Society

What Are the New Screening Tests?

The updated guidelines introduce and expand screening options beyond the traditional colonoscopy. Here's what's now recommended:

• Next-generation stool DNA test (Cologuard): An updated version of an existing at-home test that analyzes stool samples for specific DNA markers and hemoglobin, recommended every 3 years.
• Multi-target stool RNA test (ColoSense): A new at-home test that analyzes stool samples for specific RNA markers and hemoglobin, also recommended every 3 years.
• Blood-based tests (Shield): Tests that detect tumor DNA in the blood, recommended for individuals who decline or do not complete preferred screening tests.

The stool-based tests demonstrate high sensitivity for colorectal cancer and moderate sensitivity for advanced precancerous lesions. However, blood-based tests showed lower sensitivity for both advanced precancerous lesions and stage I cancers compared with stool-based tests, with studies predicting less effectiveness in reducing colorectal cancer incidence and mortality.

For any stool or blood-based screening test to be effective, a positive result requires timely follow-up with a colonoscopy, preferably within 6 months, to complete the screening process.

What Hasn't Changed in Colorectal Cancer Screening?

The guidelines continue to recommend several established screening methods that remain effective options:

• High-sensitivity guaiac-based tests (gFOBT): Traditional stool tests recommended annually.
• Fecal immunochemical tests (FIT): Stool-based tests recommended annually.
• Colonoscopy: The gold standard visual examination of the colon and rectum, recommended every 10 years.
• Flexible sigmoidoscopy: A procedure that examines only the lower third of the colon, recommended every 5 years.
• CT colonography: A test that creates 3D images of the colon and rectum to detect polyps or cancer, recommended every 5 years.

The guidelines also maintain that average-risk adults should begin colorectal cancer screening at age 45 and continue through age 75 for those with a life expectancy greater than 10 years. People at increased or high risk may need to start screening before age 45, be screened more often, or receive specific tests. Additionally, people over age 85 should no longer get colorectal cancer screening.

How to Choose the Right Screening Test for You

• Consider your comfort level: If you prefer to avoid a colonoscopy, at-home stool tests or blood tests offer convenient alternatives that you can complete in your own home without a medical procedure.
• Evaluate your risk factors: People at increased or high risk of colorectal cancer may need different screening approaches, so discuss your personal and family history with your doctor.
• Prioritize completion: The most important factor is choosing a test you will actually complete. Experts emphasize that the best screening test is the one that gets done, regardless of which option you select.
• Plan for follow-up: If you choose a stool or blood test and receive a positive result, be prepared to schedule a colonoscopy within 6 months to confirm findings and remove any precancerous polyps.

Access and affordability remain significant barriers to colorectal cancer screening. The American Cancer Society's advocacy affiliate, the American Cancer Society Cancer Action Network, continues to work at all levels of government to advance equitable screening and eliminate out-of-pocket costs.

"No matter which test you choose, what's most important is to get screened, and that includes underserved, rural, and minority populations," said Dr. William Dahut, chief scientific officer at the American Cancer Society.

Dr. William Dahut, Chief Scientific Officer at the American Cancer Society

The updated guideline report also includes a patient page supporting the new recommendations, providing evidence-based information in a structured format that addresses typical patient questions about colorectal cancer screening, symptoms, prevention, and treatment options.