The NHS-Galleri trial results came out last Friday. 142,000 participants. 3 years. The most ambitious cancer screening trial ever run.
The headlines: primary endpoint missed.
That's a fact, and it matters. But I believe the headlines are missing the deeper story in these data – one that matters enormously to patients and to the future of cancer screening.
Here's what the NHS-Galleri Test study showed:
✅ Stage IV cancer diagnoses – metastatic, typically incurable disease – declined substantially in the screened group, with >20% reductions across the 12 deadliest cancer types
✅ More cancers were found at Stage I & II, when treatment can be curative, in cancers that are typically diagnosed late (pancreatic, ovarian, liver, lung)
✅ 4x higher overall cancer detection rate when Galleri was added to standard screening (i.e., colonoscopy & mammography)
✅ Fewer cancers detected through emergency presentation – the worst possible way to learn you have cancer, and the most lethal and most costly
✅ No serious safety concerns. Test performance consistent with prior studies (with very high 99.5% specificity and very low false positive rate)
So why did the 'primary endpoint' miss? See article for more detail & perspective on the study design, and the 'Stage Migration paradox' that masks enormous progress and clinical impact for patients.