American Cancer Society Adds Blood Test to Colorectal Cancer Screening Guidelines

The American Cancer Society released an updated guideline on Wednesday that adds blood-based screening tests to its list of recommended options for colorectal cancer. The guideline applies to adults age 45 and older at average risk who have not completed or have declined visual exams and stool tests. S.

Food and Drug Administration in 2024. The guideline also adds two new stool-based tests: Cologuard Plus and ColoSense, the latter developed by Geneoscopy.

The report states that blood-based tests should be recommended only to individuals who decline or do not complete preferred screening tests. Dr. William Dahut, chief scientific officer for the American Cancer Society, said the blood test is not the first choice because it is less sensitive than other options for detecting precancerous polyps.

Dahut said the addition aims to reach people who cannot or will not undergo colonoscopy or collect stool samples. He noted that the Shield test is recommended every three years and is covered by Medicare with no co-pay for most beneficiaries.

Clinical trial data show the Shield test has approximately 83 percent sensitivity for detecting colorectal cancer and 90 percent specificity. The test performs better at identifying stage II, III, and IV cancers than stage I cancers or precancerous adenomas.

Dr. Ursina Teitelbaum of the University of Pennsylvania said the guideline is forward thinking because it broadens screening access, particularly for younger populations. Dr. Scott Kopetz of The University of Texas MD Anderson Cancer Center said future blood tests are expected to improve performance.

The American Cancer Society continues to recommend visual exams such as colonoscopy every 10 years and stool-based tests as primary options. A positive result on any non-visual test requires follow-up colonoscopy. Individuals with symptoms or higher risk factors are advised to consult a physician about colonoscopy.