The FDA recently approved the first blood-based test for colon cancer screening, and we sat down with Dr. Jay Popp, gastroenterologist and AMSURG Medical Staff Lead, to learn more about the implications.
Due to the rising number of cases of colorectal cancer (CRC) in younger adults, the U.S. Preventive Services Task Force advises individuals at average risk to undergo a baseline screening at age 45.
Regular on-time screenings remain effective tools in colorectal cancer detection and prevention. When colorectal cancer is found at an early stage before it has spread, the five-year survival rate is about 90 percent1.
Colorectal cancer screening methods include colonoscopy, stool-based tests and now a new blood test, approved in July by the U.S. Food and Drug Administration.
“I welcome new [screening] options because there are certain patients who will not wish to have colonoscopy and also who will be uncomfortable submitting their stool,” said AMSURG Medical Staff Lead Jay Popp, MD, MACG.
What Is the New CRC Screening Blood Test?
In the new CRC blood test, a person’s blood is tested for changes in DNA that could suggest the presence of cancer or precancerous cells in the body.
Dr. Popp noted that the blood test is inferior to some popular stool tests. With this blood test, colorectal cancer is identified 83 percent2 of the time when it is present.
“Blood and stool tests may be a reasonable option to detect colon cancer, but they perform very poorly when it comes to detecting precancerous polyps,” Dr. Popp added.
The only way to detect precancerous polyps is through colonoscopy, the “gold standard” of colorectal cancer screening.
“Colonoscopy is the only screening test that can not only detect colon cancer but also prevent it,” Dr. Popp said. “Since almost all colon cancers begin as a small growth called a polyp, during screening colonoscopy, these polyps can be identified and removed, thus preventing cancer from developing.”
Yet, many people decline colonoscopy for various reasons.
“Fear of the procedure and fear of what might be found could be a deterrent to some people,” Dr. Popp said. “The test requires a restricted diet the day before and laxative to clean the colon — another reason people may be reluctant to have the test. There could be issues with payment, especially in those who have no health insurance. Other issues include taking time off from work, perhaps obtaining childcare and arranging transportation to and from the procedure.”
Like stool-based screenings, if the blood-based test is positive (abnormal) a person will need a follow-up colonoscopy to determine if cancer or precancerous polyps are present. Follow-ups are recommended within six months following the abnormal test.
One-third of Americans Are Overdue for Colon Cancer Screening
An estimated 55 million3 people between 45 and 85 are eligible for a colorectal cancer screening in the United States. Yet, recent studies show one-third4 of Americans are overdue.
Individuals should talk to their healthcare providers about which screenings might be good options for them.
“People with a family history of colon cancer, certain hereditary syndromes or a history of inflammatory bowel disease should be screened earlier than age 45 and more frequently,” Dr. Popp said. “Finally, patients with digestive symptoms that may be experienced with CRC should seek medical attention regardless of age.”
It’s important to note health insurance coverage varies for colorectal cancer screening tests, so individuals should contact their providers prior to getting screened.
We would like to thank Dr. Jay Popp for sharing the considerations for this advancement in colorectal cancer screening options. AMSURG remains strongly committed to increasing awareness and screening for colon cancer prevention.
“As is often said, the best screening test is the one that gets done,” said Abbey E. Vandersall, MD, MS, AMSURG Vice President of Quality & Clinical Services. “We need to get more people screened, regardless of the method used. This is a preventable cancer, and losing over 50,000 people to this disease annually is unacceptable.”
[1] “Can Colorectal Polyps and Cancer Be Found Early?” American Cancer Society, cancer.gov, https://www.cancer.org/cancer/types/colon-rectal-cancer/detection-diagnosis-staging/detection.html. Accessed 22 August 2024.
[2] “A Cell-free DNA Blood-Based Test for Colorectal Cancer Screening.” The New England Journal of Medicine, https://www.nejm.org, https://www.nejm.org/doi/full/10.1056/NEJMoa2304714. 13 March 2024.
[3] “Estimated Average-Risk Colorectal Cancer Screening–Eligible Population in the US.” JAMA Network Open, https://www.jamanetwork.com, https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2816965. 29 March 2024.
[4] “New Study Shows Most U.S. Adults Overdue for Colorectal Cancer Screening Report not Receiving Screening Recommendation From Doctor; More in Marginalized Populations.” American Cancer Society, cancer.org, https://pressroom.cancer.org/releases?item=1252. 11 September 2023.