A test that looks at circulating DNA rather than specific mutations is accurate in detecting 72% of early cancer cases and correctly identifying the tissue of origin in 75% of cases, researchers reported in study findings published in Nature.

Using a sample of 236 patients with cancer and 245 healthy controls, researchers applied the DELFI (DNA evaluation of fragments for early interception) test to detect seven different cancers: breast, colorectal, lung, ovarian, pancreatic, gastric, or bile duct. Based on the results, DELFI had a 73% sensitivity and 98% specificity. Additionally, DELFI correctly identified 72% of the 183 patients who had stage I–III resectable disease, showing promise for early detection.

Although the study did not explore the test’s ability to detect how a patient’s cancer responds to treatment, the researchers said that it may one day be able to do that. By identifying DNA fragmentation patterns instead of mutations, the test can monitor whether abnormalities decrease (indicating positive treatment response) or increase (indicating treatment failure).