A groundbreaking cancer blood test, hailed as a potential game-changer for healthcare, faced setbacks in its NHS trial as it fell short of its primary objective. The innovative Galleri test, capable of detecting early signs of various cancers by analyzing tumor DNA fragments in the blood before symptoms manifest, underwent a three-year evaluation involving over 142,000 NHS patients aged 50 to 77. While the trial, costing £150 million, aimed to lower the incidence of stage three and four cancer diagnoses, it did not achieve this target. Nonetheless, there were some positive outcomes noted.
Although the number of stage four cancer diagnoses decreased by over 20%, there was a rise in stage three diagnoses, which experts attributed to the earlier detection and reclassification of some stage four cases. Developed by GRAIL, a US biotech firm, the Galleri test is a Multi-Cancer Early Detection (MCED) tool designed to screen for more than 50 cancer types from a single blood sample, often identifying cancers before symptoms appear.
Despite these findings, GRAIL’s chief medical officer, Julie Gralow, indicated that the test might not gain NHS approval based on the trial results. Concerns were also raised by Professor Richard Houlston from The Institute of Cancer Research in London, cautioning against shifting focus to positive aspects while missing the primary goal. He suggested that the ultimate test for such a screening tool would involve a long-term trial assessing patient survival rates. However, the time-consuming nature of such trials poses challenges as technology advances rapidly.
Professor Peter Johnson, national clinical director for cancer at NHS England, emphasized the importance of early cancer detection in line with the National Cancer Plan. He expressed eagerness to review the trial data in detail to inform future decisions within the NHS regarding cancer screening strategies. The mixed results of the Galleri test were presented at the American Society of Clinical Oncology’s annual conference in Chicago.
