Health
A groundbreaking blood test capable of detecting more than 50 types of cancer could significantly speed up diagnosis and improve survival rates, according to a new study. Results from a large-scale trial in North America showed that the test was able to identify a wide range of cancers—three-quarters of which currently have no screening programme—and detected more than half of them at an early, more treatable stage.
The test, known as Galleri, is developed by American biotechnology company Grail. It works by detecting tiny fragments of cancerous DNA that have broken away from tumours and are circulating in the bloodstream. The test is also being trialled by the UK’s National Health Service (NHS).
Promising Results from the Trial
The trial followed 25,000 adults from the United States and Canada for one year. Nearly 1 in 100 participants received a positive test result, and among those, 62% were later confirmed to have cancer. Lead researcher Dr. Nima Nabavizadeh, Associate Professor of Radiation Medicine at Oregon Health & Science University, said the data suggests the test could “fundamentally change” how cancer is detected and managed.
He explained: “It could help identify many cancers earlier, when the chances of successful treatment or even cure are greatest.” The test also demonstrated a high degree of accuracy, correctly ruling out cancer in more than 99% of participants who tested negative.
When combined with existing screening programmes for breast, bowel, lung, and cervical cancers, the addition of the Galleri test increased overall cancer detection seven-fold.
Early Detection Where No Screening Exists
Crucially, three-quarters of the cancers detected were those for which no standard screening programme currently exists, including ovarian, liver, stomach, bladder, and pancreatic cancers. In nine out of ten cases, the test was also able to correctly identify the tissue of origin — a key step in guiding treatment. These findings indicate the potential for the blood test to revolutionize early cancer diagnosis and treatment outcomes.
Experts Call for More Evidence
Despite the promising data, scientists not involved in the research have urged caution.
Professor Clare Turnbull, a translational cancer genetics expert at The Institute of Cancer Research, London, said that more rigorous testing is needed before the Galleri test can be widely adopted.
“Data from randomized studies, with mortality as an endpoint, will be absolutely essential to establish whether seemingly earlier-stage detection by Galleri translates into benefits in mortality,” she said.
The topline results were presented at the European Society for Medical Oncology (ESMO) Congress in Berlin on Saturday. Full findings are expected to be published in a peer-reviewed journal later this year.
Next Steps for NHS Trials
The NHS is currently running a three-year trial involving 140,000 patients in England, with results expected next year. If successful, the health service plans to extend the testing to an additional one million people.
Sir Harpal Kumar, President of Biopharma at Grail, described the findings as “very compelling.”
"The vast majority of people who die from cancer do so because we find their cancers too late. Our goal is to shift to earlier detection—when treatments are much more effective and potentially curative.”
However, Naser Turabi of Cancer Research UK urged careful evaluation before mass adoption, warning that early testing could risk overdiagnosis—detecting cancers that might never have caused harm.
“The UK National Screening Committee will play a critical role in reviewing the evidence and determining whether these tests should be adopted by the NHS,” he added.
If proven effective, the Galleri blood test could mark one of the most significant advances in cancer detection in decades—transforming the way cancers are diagnosed and saving countless lives through earlier intervention.
Source: BBC
