A blood-based screening option for colorectal cancer (CRC) for the general population (>45 years) is now FDA approved.
The Shield® blood test was approved by the regulatory body as a screening option for average-risk individuals who are at least 45 years of age. You are considered to be average risk when you do not have:
- A family history of CRC
- A personal history of CRC or polyps
- A personal history of inflammatory bowel disease/IBD (Crohn’s disease or ulcerative colitis)
- A hereditary CRC syndrome (Lynch or FAP)
- A personal history of getting radiation to the abdominal or pelvic area
Why is the approval of this test exciting news? Because this has the potential to improve screening rates for the second leading cause of cancer-related deaths in the country. And CRC is highly treatable if caught early!
A recent study published in JAMA estimated that approximately 60 million average-risk individuals in the U.S. will be eligible for CRC screening in 2025. Widespread screening has remained a struggle in the country, with barriers such as lack of awareness of CRC and its symptoms among both clinicians and the general population, fear/apprehension about the screening procedure, fear of the outcome, financial concerns with testing, and challenges with transportation.
For colonoscopy in particular, the person is required to take a day off from work and someone to drive them home following the procedure, since they are recovering from anesthesia. For others, the prep required a day before the test can seem daunting. This may lead to a delay in screening or avoiding the procedure altogether. The routine nature of a blood draw makes the screening process a lot less daunting.
The test has been shown to have 83% sensitivity for detection of CRC and 90% specificity for advanced neoplasias, and 13% sensitivity for advanced precancerous lesions. According to the manufacturer (Guardant Health), Medicare is expected to cover this test for eligible individuals, while commercial insurers will follow suit only after guideline inclusion by the American Cancer Society and the U.S. Preventive Services Task Force.
While welcoming this approval, experts are emphasizing that a positive result on the Shield test has to be confirmed with a colonoscopy.