Colorectal cancer screening just got a new option — but physicians are concerned that the most important fact about this new test is getting lost in the enthusiasm for a less invasive alternative to colonoscopy.
In May 2026, the American Cancer Society updated its colorectal cancer screening guidelines to include the Shield blood test, developed by Guardant Health, as a qualifying screening option for average-risk adults. The Shield test requires only a blood draw and no bowel preparation — making it substantially more accessible for patients who have declined or delayed colonoscopy for years.
