A recent study, known as PATHFINDER 2, has showcased promising results for a new blood test, Galleri, which claims to detect over 50 types of cancer. Results from this interventional screening trial, presented at the European Society for Medical Oncology Congress 2025, indicate a significant increase—over seven-fold—in cancer detection rates when Galleri is used alongside standard screenings. Notably, more than half of the detected cancers were identified at early stages (stage I or II), enhancing treatability.
Approximately 75% of the cancers identified by Galleri lack existing standard screening protocols, such as pancreatic and ovarian cancers. Dr. Josh Ofman, President of GRAIL, highlighted the critical need for early detection, as many cancers are typically diagnosed too late, leading to higher mortality rates.
The UK’s National Health Service (NHS) is currently incorporating the Galleri test into one of its largest screening studies, enrolling over 140,000 participants. Expected topline results next year may pave the way for a broader implementation, potentially marking the first national multi-cancer early detection program globally.
Experts emphasize that successful early detection could not only improve treatment outcomes but also reduce the economic burden associated with late-stage cancer care. Galleri operates by analyzing cell-free DNA from tumors in the bloodstream, boasting a specificity rate of 99.6% and a positive predictive value of approximately 62%. Additionally, it can pinpoint the cancer's origin in 92% of cases, allowing for more targeted diagnostics.
While the initial findings are encouraging, researchers stress that further studies are necessary to determine if early detection translates to improved survival rates. As trials progress, Galleri may significantly influence cancer screening practices worldwide, shifting focus from late-stage treatment to proactive prevention.