Effect of screening with multicancer early-detection test on late-stage cancer diagnosis.

Multicancer early-detection tests could change how cancers are identified, but earlier detection does not automatically improve patient outcomes. This UK randomized controlled Galleri trial evaluated whether screening with a multicancer early-detection test affected late-stage cancer diagnosis. The results find that adding a multicancer blood test to usual care didn't reduce late-stage cancers over three screening rounds, but longer follow-up is needed to see how results change over time. Its findings are relevant to screening policy, diagnostic pathways, and overdiagnosis.