A blood test called DENEB detected 92 percent of stage I to III colorectal cancers and 81 percent of advanced adenomas, the precancerous polyps that often precede cancer, in a study of more than 1,500 adults screened by colonoscopy in China, Japan and Spain.
The findings were published on August 10, 2026 in The Lancet Gastroenterology and Hepatology. The test is experimental and not yet approved by the U.S. Food and Drug Administration.
Most blood-based colorectal tests are good at spotting existing cancer but poor at catching the precancerous growths that give doctors a chance to prevent cancer altogether. The Shield test from Guardant Health, which the FDA approved in July 2024 as the first blood test for primary colorectal cancer screening, picked up about 83 percent of colorectal cancers but only 13 percent of advanced adenomas in its pivotal trial.
How DENEB works
DENEB analyzes microRNAs, small molecules that help control how genes switch on and off. It combines microRNAs circulating freely in blood with microRNAs carried inside tiny membrane-bound particles called exosomes to identify molecular signals tied to colorectal abnormalities.
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The test also correctly identified about 85 percent of people without advanced precancerous lesions, keeping the false-positive rate in a range acceptable for a screening tool.
Why the polyp number matters
Advanced adenomas are growths in the colon that carry a real risk of turning into cancer over time. When a doctor removes them during colonoscopy, that cancer never develops. A blood test that flags these lesions could route the people who most need a colonoscopy toward one, and reassure those who do not.
Ajay Goel, PhD, professor and founding chair of the Department of Molecular Diagnostics and Experimental Therapeutics at the Beckman Research Institute of City of Hope in Duarte, California, developed the test and led the international research team. Detecting colorectal cancer early, at stage I or at the advanced polyp stage, gives patients the best chance of a cure.
What it means for screening now
The U.S. Preventive Services Task Force recommends colorectal cancer screening for adults aged 45 to 75. Options include colonoscopy every 10 years, annual stool-based tests, and stool DNA testing every one to three years. Screening rates lag partly because the preparation and the procedure put people off, and the idea of a routine blood draw picking up the same disease has been the goal of the field for years.
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DENEB is not on the market. The researchers say larger prospective studies in real screening populations are still required before the test could be considered for approval, and Goel has said a blood test like DENEB could eventually move screening from finding colorectal cancer earlier to helping prevent some cancers from developing at all.
For readers already covered by current guidelines, a blood test that could one day replace an unpleasant cancer examination is not a reason to postpone. Getting screened cuts the risk of dying from colorectal cancer by nearly half, and the USPSTF advises starting at age 45.
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This article is made and published by Jesper Bengtson, who may have used AI in the preparation.