Performance of a multi-cancer early detection test in the randomized controlled NHS-Galleri trial

Secondary endpoint analyses from the randomized controlled NHS-Galleri trial report how a blood-based multi-cancer early detection test performed when added to usual care in more than 142,000 participants who had no clinical suspicion of cancer. The study is the largest randomized evaluation to date of a circulating-tumour-DNA screening test applied to an asymptomatic general population, and it quantifies detection rates and diagnostic accuracy under real screening conditions rather than in enriched case-control cohorts. These performance data are central to deciding whether such tests can be deployed at population scale, although the trial's key mortality and stage-shift outcomes remain the decisive test of clinical benefit.