The U.S. Food and Drug Administration (FDA) has approved the first stool-based colorectal screening test, and the Centers for Medicare & Medicaid Services (CMS) is proposing covering it under some circumstances, but the independent U.S. Preventive Services Task Force (USPSTF) currently doesn't recommend the test for screening.
Using a stool sample, Cologuard detects hemoglobin as well as certain mutations associated with colorectal cancer in the DNA of cells shed by advanced adenomas as stool moves through the large intestine and rectum. Those with positive test results are advised to undergo a diagnostic colonoscopy.
“Fecal blood testing is a well-established screening tool, and the clinical data showed that the test detected more cancers than a commonly used fecal occult test,” says Alberto Gutierrez, PhD, director of the Office of In Vitro Diagnostics and Radiological Health at the FDA’s Center for Devices and Radiological Health.
The approval, however, does not change current practice guidelines for colorectal cancer screening, according to the FDA. The USPSTF, a non-government body, currently does not recommend fecal DNA testing as a method to screen for colorectal cancer. Among other guidelines, the USPSTF recommends that adults aged 50 to 75 years who are at average risk for colon cancer be screened using fecal occult blood testing, sigmoidoscopy or colonoscopy.
CMS has issued a proposed national coverage determination for Cologuard that would pay for the test once every three years for Medicare beneficiaries who meet all of the following criteria:
- aged 50 to 85 years,
- asymptomatic (no signs or symptoms of colorectal disease including but not limited to lower gastrointestinal pain, blood in stool, positive guaiac fecal occult blood test or fecal immunochemical test) and
- average risk of developing colorectal cancer (no personal history of adenomatous polyps, of colorectal cancer, or inflammatory bowel disease, including Crohn’s disease and ulcerative colitis; no family history of colorectal cancers or an adenomatous polyp, familial adenomatous polyposis, or hereditary nonpolyposis colorectal cancer).
Cologuard is manufactured by Exact Sciences in Madison, Wisconsin.