Additional Considerations
The AGA CRC Workshop Panel met in September 2023 to review the two modeling studies and other data on blood-based tests for CRC. Overall, the group concluded that a triennial blood test that meets minimal CMS criteria would likely result in better outcomes than no screening and provide a simple process to encourage more people to participate in screening.
However, patients who may have declined colonoscopy should understand the need for a colonoscopy if blood-based tests show abnormal results, the commentary authors wrote.
In addition, because blood-based tests for CRC appear to be less effective and more costly than current screening options, they shouldn’t be recommended to replace established screening methods. Although these blood-based tests may improve screening rates and outcomes in unscreened people, substituting blood tests for other effective tests would increase costs and worsen patient outcomes.
Beyond that, they wrote, the industry should consider other potential benchmarks for an effective blood test, such as a sensitivity for stage I-III CRC of greater than 90% and sensitivity for advanced adenomas of 40%-50% or higher.
University of California San Diego
Dr. John M. Carethers
“Unless we have the expectation of high sensitivity and specificity, blood-based colorectal cancer tests could lead to false positive and false negative results, which are both bad for patient outcomes,” John M. Carethers, MD, AGAF, vice chancellor for health sciences at UC San Diego, AGA past president, and a member of the AGA CRC Workshop panel, said in a statement.
Several authors reported consultant roles and funding support from numerous companies, including Guardant Health and Freenome.