FDA Gives Green Light for New Blood Test for Early Detection of Colon Cancer

In a significant step towards improving early detection of colorectal cancer, the US Food and Drug Administration (FDA) on Monday approved a new blood test that can detect particularly early and treatable stages of colorectal cancer. This blood test presents an easier alternative to colonoscopy or stool sample, as it only requires a blood draw in a doctor's office or a commercial lab. The test, named Shield, developed by Guardant Health from Palo Alto, California, will be available within a week. A company spokesperson, Matt Burns, announced that the list price of the test will be disclosed at that time. The test targets individuals aged 45 and older who are at average risk for colorectal cancer. Although the Shield test boasts a high success rate in detecting early-stage colorectal cancer, it shows weaknesses in identifying precancerous growths. Removing these growths early could prevent the onset of cancer. Nevertheless, experts hope that the easy access to the blood test could encourage more people to routinely screen for colorectal cancer. It is expected that up to 53,000 Americans could die from colorectal cancer this year, the second leading cause of cancer-related deaths in the United States. Regular screenings could prevent up to 73% of these deaths. Current guidelines recommend corresponding screenings starting at age 45, but still, 25% to 50% of the affected individuals do not get tested. Here, the new blood test could provide relief through its simplicity. The Shield test detects DNA fragments originating from cancer cells and large polyps that can sometimes develop into cancer. A study published on March 13 in the New England Journal of Medicine found that the Shield test detected 87% of early-stage cancers. The five-year survival rate for early-stage cancers is an impressive 91%, while it is only 14% for advanced cancer. However, the test has a 10% false-positive rate and only detects 13% of large polyps compared to 95% during a colonoscopy. On May 23, an FDA advisory committee recommended the test's approval but pointed out its limitations in cancer prevention. Existing screening methods include stool tests conducted every three to five years or a colonoscopy every ten years. Many patients shy away from the effort and discomfort of these procedures. The new blood test could represent a more attractive option, even if positive results necessitate a follow-up colonoscopy. Guardant Health emphasized that the test meets the requirements for Medicare coverage. For Medicare Part B holders, there should be no additional costs, while expenses for individuals with commercial insurance or Medicare Advantage depend on the respective plan.