Performance of a multi-cancer early detection test in the randomized controlled NHS-Galleri trial
In brief
Galleri detected 27% to 37% of cancers across three screening rounds
In the NHS-Galleri trial, the test's sensitivity for all cancers ranged from 27% to 37% across three annual rounds, while 99.5% to 99.6% of people without cancer screened negative. A positive result indicated cancer in 46% to 58% of cases, but the trial did not meet its primary goal of reducing advanced cancer diagnoses; whether screening improves outcomes remains unproven.
- Journal
- Nature medicine (Q1)
- Published
- 22 September 2026
- Study design
- Randomized controlled trial
- Evidence level
- Level 1, High (CEBM 1b)
- Authors
- Richard D Neal, Saoirse Dolly, Peter Johnson, Helen Jones, Sir Harpal Kumar, Lennard Y W Lee, et al.
- PMID
- 42773209
- DOI
- 10.1038/s41591-026-04652-8
Why clinicians should know about it
- Picked for Gastrointestinal and Colorectal Surgery (top studies of the week, 27 September 2026): Screening test performance, not surgical oncology
- Picked for Family Practice (top studies of the week, 27 September 2026): Multi-cancer early detection test performance in population screening
- Picked for Oncology and Radiation Oncology (top studies of the week, 27 September 2026): Multi-cancer early detection test performance in population screening
- Picked for Pediatric Surgery (top studies of the week, 27 September 2026): Not surgical pediatric focus
- Picked for Radiation Oncology (top studies of the week, 27 September 2026): High-quality evidence in a top journal
- Picked for Spine Surgery (top studies of the week, 27 September 2026): High-quality evidence in a top journal
- Picked for Surgical Oncology (top studies of the week, 27 September 2026): Not surgical oncology focus
- Picked for Bariatric and Metabolic Surgery (top studies of the week, 27 September 2026): Not related to bariatric surgery outcomes
Abstract
The NHS-Galleri trial was a randomized controlled trial evaluating a multi-cancer early detection (MCED) test added to usual care. We reported elsewhere that the primary endpoint of a reduction in the incidence of stage III/IV cancer diagnoses in the intervention arm versus control arm was not met. Here we report prespecified secondary test performance endpoints among evaluable intervention arm participants across three annual screening rounds. These analyses were descriptive; there was no hypothesis testing. Participants aged 50-77 years (N = 142,250) were randomized 1:1 into intervention (MCED) or control arms. Intervention arm participants with positive MCED results were referred to National Health Service (NHS) standard-of-care pathways for diagnostic workup, with referrals informed by the predicted cancer signal origin (CSO). Positive test results were returned for 722 of 70,325 (1.03%), 518 of 64,498 (0.80%) and 561 of 62,323 (0.90%) participants in rounds 1-3, respectively. In aggregate, 937 participants had MCED-detected primary cancers. Respective by-round cancer detection rates were 0.60%, 0.40% and 0.41%; positive predictive values were 58.0% (419/722), 50.4% (261/518) and 45.8% (257/561); and negative predictive values were 98.98% (68,895/69,603), 98.90% (63,278/63,980) and 98.86% (61,058/61,762). Across rounds, specificity ranged from 99.50% to 99.60%; episode sensitivity ranged from 26.7% to 37.2% for all cancers and from 47.6% to 63.4% for 12 prespecified types; and CSO accuracy ranged from 91.1% to 93.6%. These data provide insights on the performance of the MCED test in population screening within the NHS setting. ClinicalTrials.gov: NCT05611632 ; ISRCTN: ISRCTN91431511 .
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.