Blood Test Now an Option for Colorectal Cancer Screening, Cancer Society Says

The American Cancer Society updated its colorectal cancer screening guidelines on May 27, 2026, adding a blood-based test to the list of approved options for average-risk adults aged 45 and older.

The test, called Shield and developed by Guardant Health, received FDA approval in 2024. It works by detecting tumor-derived DNA shed into the bloodstream. Under the new guidelines, the test is recommended every three years.

Doctors are clear that the blood test is not a replacement for colonoscopies. The Shield test detects about 83% of colorectal cancers but is less effective at finding early-stage tumors and precancerous polyps. A colonoscopy can both detect and remove polyps during the same procedure.

The ACS added the test specifically to reach the roughly one-third of eligible adults who currently do not get screened. Colorectal cancer is now the leading cause of cancer death among U.S. adults under age 50, making screening rates a public health priority.

The updated guidelines also include two newer at-home stool-based tests: Cologuard Plus, an updated multi-target stool DNA test, and ColoSense, a new multi-target stool RNA test. Both are recommended every three years.

Insurance coverage for the blood test remains uncertain. The U.S. Preventive Services Task Force has not yet updated its guidelines to include blood-based screening, and coverage typically follows USPSTF recommendations. The Shield test costs between $895 and $1,495 out of pocket for patients without coverage.

Experts say the most effective screening test is the one a patient actually completes.