Advantages of Blood-Based Colorectal Cancer Screening: An Expert Discussion

Traditional methods like colonoscopy and fecal immunochemical tests have long been the standard in colorectal cancer (CRC) screening, but their limitations—such as patient discomfort, preparation requirements, and accessibility barriers—often lead to low compliance rates. In the video above, William Grady, MD—a professor in the public health sciences division at the Fred Hutchinson Cancer Center in Seattle, WA—discusses how blood-based testing offers a more convenient, accessible, and patient-friendly alternative, potentially transforming how we screen for CRC. Dr Grady also talks about how a new class of tests based on circulating free DNA in the blood, such as Guardant Health’s recently approved Shield test, could have broader applications in early cancer detection.

Dr Grady is also the Rodger C. Haggitt professor in the division of gastroenterology at the University of Washington School of Medicine and corresponding author of the ECLIPSE clinical trial evaluating the Shield cfDNA blood-based test. For details on the ECLIPSE trial, watch part 1 of our interview with Dr Grady, here.