A simple blood test that can detect more than 50 types of cancer, even before symptoms appear, could transform early diagnosis and save thousands of lives, researchers say.

The Galleri test, developed by U.S. biotech company Grail, works by identifying tiny fragments of tumor DNA circulating in the bloodstream. Dubbed the ‘holy grail’ of cancer screening, it is currently being trialed by the UK’s NHS and in large-scale U.S. studies.

New findings suggest the test is even more effective than previously thought. It correctly identified that more than a third of patients previously told they were “false positives” actually did have cancer within two years.

In 92%of these cases, the test also accurately pinpointed the organ or tissue where the disease originated.

The Pathfinder 2 study, which examined the test’s use in real-world settings alongside standard NHS screening, found that over half (53.5%) of new cancers detected were at the earliest stage, when treatment is most effective. More than two-thirds (69.3%) were found at later stages.

Experts say the test could be a gamechanger for GPs, helping them direct patients to the right scans sooner and significantly improving outcomes.

A major U.S. trial involving more than 23,000 patients also found the Galleri test detected 74% of cases across the 12 deadliest cancers, including bowel and lung cancers.

“This suggests it wasn’t a false positive at all,” said Harpal Kumar, president of International Business and BioPharma at Grail and former head of Cancer Research UK. “We have something that could really help GPs send patients to the right clinic quickly.”

Full results are expected to be presented this week at the Early Detection of Cancer Conference in Oregon, U.S. While not yet published in a peer-reviewed journal, the findings have strengthened hopes that the Galleri test could soon become part of routine cancer screening programs.

Cancer is one of the leading causes of death in Greece. One in four deaths in 2019, were attributed to cancer, highlighting the pressing need for enhanced prevention, early detection, and treatment strategies