ASCO said it will not recommend Grail’s Galleri multicancer early detection test for routine use after reviewing follow-on evidence from the NHS-Galleri randomized trial. The trial did not meet its primary endpoint, and ASCO emphasized that the assay should not be incorporated into cancer screening guidelines at this time. ASCO leadership acknowledged signals that could matter clinically—such as fewer stage IV cancers and more stage I/II detections over three years—but concluded the results remain insufficient to clear guideline standards. For clinicians already considering early-access pathways, the decision sets a clear boundary around evidence thresholds. The move highlights how MCED adoption may hinge on endpoint design and on whether benefits consistently outweigh risks such as downstream testing and diagnostic delays.