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 and stool-based tests. This update aims to increase screening rates, especially among younger populations experiencing a rise in colorectal cancer cases.
New Screening Options
Colonoscopies remain the gold standard for detecting colorectal cancer, allowing doctors to examine the colon and rectum for signs of disease. However, many individuals skip screenings due to the invasive nature of these tests. To address this, the American Cancer Society now recommends blood-based tests, such as the Shield test by Guardant Health, approved by the FDA in 2024. This test is suggested for adults aged 45 and older who are at average risk and have not completed other screening methods.
The Shield test detects signals for colorectal cancer from tumor DNA in the blood, with a recommended screening every three years. Although it is not as sensitive as colonoscopies or stool tests, it provides an option for those unwilling to undergo traditional screenings. If the test returns a positive result, a follow-up colonoscopy is advised.
Additional Testing Options
Alongside the Shield test, the updated guidelines include new stool-based tests like Cologuard Plus and ColoSense, which detect molecular markers associated with colorectal cancer. These at-home tests require samples to be sent to a lab for analysis. While blood-based tests are not the first choice due to lower sensitivity for early-stage cancers, they offer a viable alternative for those who decline other methods.
Experts emphasize the importance of screening, as early detection significantly improves survival rates. Over 90% of individuals who detect colorectal cancer at stages I and II survive at least five years. Screening also reduces the risk of developing cancer by identifying and removing precancerous polyps.
Dr. William Dahut of the American Cancer Society highlights that the updated guidelines are for adults at average risk. Those with a personal or family history of colorectal cancer should consult their doctor for appropriate screening options. Blood-based tests are covered by Medicare, making them accessible to many patients.
Original reporting: KEYT (Ventura/Santa Barbara) — read the source article.
