The FDA has approved Guardant Health’s blood test, Shield, to screen for colon cancer. This test, which detects cancerous DNA in the bloodstream, could significantly increase screening rates, particularly among adults under 50 who are too young for routine colonoscopies. Shield is not a replacement for colonoscopies but is expected to be more accessible with insurance coverage, potentially improving early detection and reducing colorectal cancer mortality rates.

Despite its promise, the Shield test detects only 13% of early-stage polyps and is most effective for later-stage cancers. Positive results require follow-up colonoscopies for confirmation. Experts emphasize that while the test could boost screening compliance due to its convenience, colonoscopy remains the most accurate screening method. This new test could address the low screening rates, with fewer than 60% of eligible individuals currently screened, and potentially save lives through earlier detection.