A new experimental blood test detected 92 percent of early-stage colorectal cancers and 81 percent of precancerous polyps in a multicenter clinical trial, according to Healthline. The results, published in The Lancet Gastroenterology and Hepatology on August 10, involve a test called DENEB and have drawn attention from researchers who say most blood-based cancer screens have struggled with exactly what this one appears to do well.
The trial tested more than 1,500 adults enrolled in colonoscopy screening programs in China, Japan, and Spain. Researchers measured how often the DENEB test correctly identified colorectal cancers across stages I, II, and III, as well as advanced adenomas, which are polyps that can turn into cancer if not removed.
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, and a co-author of the study, said the polyp detection number was the most significant part of the findings. "Many blood-based screening tests are very good at finding cancer, but have struggled to detect these precursor lesions," he said.
That distinction matters. Colorectal cancer is one of the more preventable cancers precisely because it usually develops slowly from polyps that can be removed before they become malignant. A test that finds those polyps could shift the role of blood screening from early detection to actual prevention.
Goel said the broader goal is access. "The larger opportunity is to make screening easier and more accessible. A blood test could be incorporated into a routine medical visit to help identify people who should undergo [a] colonoscopy, particularly those who might otherwise avoid traditional screening," he said.
He also noted that more research would need to confirm the results before any change in clinical practice. "If these findings are confirmed in prospective screening studies, a blood test like DENEB could potentially help us move from simply finding colorectal cancer earlier to actually preventing some cancers from developing," he said.
Currently, colonoscopy and stool-based tests remain the standard for colorectal cancer screening. One blood test, called Shield, is already approved and available, but guidelines from the American Cancer Society say it should only be used when patients are unwilling to undergo a visual or stool-based test. The DENEB test is not yet approved and is considered experimental.
Ketan Thanki, MD, a board-certified colorectal surgeon with the MemorialCare Todd Cancer Institute at Long Beach Medical Center in California who was not involved in the study, said the results were encouraging. If the findings can be reproduced, he told Healthline, clinicians will be one step closer to using blood-based tests widely for colorectal cancer screening and being able to avoid routine colonoscopies.
The DENEB test showed stronger sensitivity than Shield, particularly in detecting precancerous polyps, though direct comparisons between tests carry limitations since they are not tested under identical conditions. Researchers and outside physicians both noted that additional prospective studies will be needed before DENEB can be considered for routine clinical use.
