The American Cancer Society has expanded its colorectal cancer screening guidelines to include blood tests, providing an alternative for those who avoid traditional methods like colonoscopies or stool-based tests. This update aims to increase screening participation, especially as colorectal cancer cases rise among younger adults.
New Screening Options
While colonoscopies remain the gold standard for detecting colorectal cancer, the addition of blood-based tests offers a less invasive option. The Shield test, developed by Guardant Health and approved by the FDA in 2024, is now recommended for adults aged 45 and older who are at average risk and have not completed or declined other screening methods.
Dr. William Dahut, chief scientific officer for the American Cancer Society, emphasizes that blood tests should only be used by individuals who refuse or cannot complete other preferred screenings. Although the Shield test is less sensitive in detecting early-stage cancers compared to colonoscopies or stool tests, it provides a viable option for those unable to undergo these procedures.
Benefits and Limitations
Screening is crucial for early detection and treatment of colorectal cancer, significantly improving survival rates. Colonoscopies and stool tests can identify precancerous polyps, allowing for early intervention. Blood tests, while less effective at detecting early-stage cancers, can still play a role in increasing screening rates.
Dr. Ursina Teitelbaum from the University of Pennsylvania notes that while blood-based testing is not perfect, it broadens the scope of screening, particularly for younger populations. Dr. Scott Kopetz from MD Anderson Cancer Center adds that future advancements in blood-based testing may further reduce barriers to effective screening.
The Shield test, covered by Medicare, involves a simple blood draw and is recommended every three years. If a positive result is returned, a follow-up colonoscopy is advised. The test’s sensitivity for detecting colorectal cancer is approximately 83%, with a specificity of 90%.
For those with a personal or family history of colorectal cancer or other risk factors, a colonoscopy remains the recommended screening method. Symptoms such as bleeding, abdominal pain, or changes in stool should prompt immediate medical consultation.
Original reporting: El Paso News (HLL/CB) — read the source article.
