Screening for many cancers with one blood test

How far are multi-cancer blood tests from routine screening?

Multi-cancer early detection (MCED) blood tests look for signs of many cancer types in one sample. GRAIL's Galleri test was studied in a trial of 142,250 people in England. The trial missed its primary endpoint of fewer stage III and IV cancers, but reported a 14% reduction in stage IV diagnoses, which GRAIL describes as nominally statistically significant. In September 2026 a US FDA advisory panel voted 7 to 2 that benefits outweigh risks. The FDA has not yet decided, and no study has yet shown fewer cancer deaths.

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WHERE WE AREPilots

Close. Early pilots are running in the real world.

The test has been studied in a large trial in England and in US pilot studies, and GRAIL has submitted it for FDA premarket approval. The FDA advisory panel reviewed it in September 2026, but the FDA has not made a decision, and the test has not been cleared or approved. No national screening programme has adopted it. The stage is pilot: tested in real populations, but not yet approved or used in a national programme.

The tech tree

Everything recorded on Vrulum that this future needs, oldest foundations at the top and the goal at the bottom. Lines show what each step requires.

What it takes: Screening for many cancers with one blood test Unlocked Being researched Locked
  1. 2023Multi-cancer early detection blood testsPilot and early commercial Unlocked.
  1. 2023Pilot study in US adults aged over 50 (PATHFINDER)Done Unlocked.
  2. 2025Second US study reports pre-specified analysis (PATHFINDER 2)Done Unlocked.
  3. 2026FDA premarket approval application submittedDone Unlocked.
  4. 2026Large trial in England completes three screening rounds (NHS-Galleri)Done Unlocked.
  5. 2026FDA advisory panel reviewDone Unlocked.
  6. Date not recordedPrimary endpoint: fewer stage III and IV cancers in the trialDone Unlocked.
  7. Date not recordedFDA decision on approvalNot started Locked.
  8. Date not recordedUK national screening recommendation and NHS rollout decisionIn progress Being researched.
  9. Date not recordedEvidence that earlier detection reduces cancer deathsNot started Locked.
  1. GoalScreening for many cancers with one blood testGoalRequires: Multi-cancer early detection blood tests, Pilot study in US adults aged over 50 (PATHFINDER), Second US study reports pre-specified analysis (PATHFINDER 2), Large trial in England completes three screening rounds (NHS-Galleri), Primary endpoint: fewer stage III and IV cancers in the trial, FDA premarket approval application submitted, FDA advisory panel review, FDA decision on approval, UK national screening recommendation and NHS rollout decision, Evidence that earlier detection reduces cancer deaths. Locked.

The road so far

6 of 9 steps done, 1 in progress.

  1. Done · 5 Oct 2023Pilot study in US adults aged over 50 (PATHFINDER)

    PATHFINDER enrolled 6,662 adults over 50 without symptoms suggestive of cancer. It was a pilot, non-randomised study. The refined test had a positive predictive value (PPV) of 43.1%, and 48% of confirmed cancers were stage I or II. GRAIL's release says larger controlled trials are needed to establish clinical utility and cost-effectiveness. [7]

  2. Done · 18 Jun 2025Second US study reports pre-specified analysis (PATHFINDER 2)

    GRAIL's June 2025 top-line release reported the pre-specified analysis of 25,578 participants. The release gave no numerical sensitivity, specificity or PPV for PATHFINDER 2. [6]

  3. Done · 19 Feb 2026Large trial in England completes three screening rounds (NHS-Galleri)

    NHS-Galleri enrolled 142,250 people aged 50 to 77 in England and tested adding the blood test to standard screening over three rounds. GRAIL's top-line release of 19 February 2026 reported the results, and full results were presented at ASCO on 30 May 2026. The full results have not been published in a peer-reviewed journal, according to GRAIL. [2][1]

  4. DonePrimary endpoint: fewer stage III and IV cancers in the trial

    Not met. The combined stage III and IV incidence rate ratio for 12 prespecified cancers was 1.03 (95% CI 0.92 to 1.14), which GRAIL describes as no statistically significant difference. A prespecified secondary endpoint did show fewer stage IV diagnoses: an incidence rate ratio of 0.86 (95% CI 0.744 to 0.998), a 14% reduction that GRAIL describes as nominally statistically significant. Reductions were 9%, 22% and 26% across the three rounds, and the first round's interval includes no reduction. [1][2]

  5. Done · 29 Jan 2026FDA premarket approval application submitted

    GRAIL submitted the final module of its premarket approval (PMA) application on 29 January 2026. The submission relied on PATHFINDER 2 data and first-year NHS-Galleri data. The FDA designated the test a Breakthrough Device in 2018, which is not an approval. [5]

  6. Done · 23 Sept 2026FDA advisory panel review

    The Molecular and Clinical Genetics Panel met on 23 September 2026. Trade press reports that it voted 7 to 2, with one abstention, that benefits outweigh risks, and 6 to 4 on effectiveness, for adults aged 50 or older. All voting members supported safety. Performance analyses presented to the panel used retrospective testing of stored plasma samples. [3][4]

  7. Not startedFDA decision on approval

    GRAIL's August 2026 release describes the panel meeting as the next step and does not describe a final FDA decision. The test is not cleared or approved. [3][5]

  8. In progressUK national screening recommendation and NHS rollout decision

    The UK National Screening Committee recommends a screening programme only when robust, peer-reviewed, published evidence shows it will do more good than harm. The sources reviewed did not show a committee recommendation on Galleri. The BMJ reported in 2024 that NHS England said it would wait for the final trial results before deciding on rollout. This is journalists' reporting of NHS England's position, not a primary NHS England statement. [9][8]

  9. Not startedEvidence that earlier detection reduces cancer deaths

    No reduction in cancer deaths has been reported. GRAIL's February 2026 release says GRAIL plans to extend the trial's follow-up by 6 to 12 months. The release does not report a mortality endpoint or cancer-death results. [2]

Why it matters

A single blood test that catches several cancer types early could widen screening beyond the few cancers screened for today. The same tests also produce false alarms that lead to invasive follow-up, so any benefit has to be shown in people, not only in detection figures. The main open question is whether finding cancers earlier saves lives.

What stands in the way

  • The NHS-Galleri trial missed its primary endpoint of fewer stage III and IV cancers. The stage IV reduction is a secondary endpoint, and the trial's full results are not yet peer-reviewed.
  • No reduction in cancer deaths has been shown. Follow-up is to be extended by 6 to 12 months, and no mortality results are available.
  • Sensitivity is low for many cancers and stages. In NHS-Galleri, GRAIL reports 30.7% across all cancer types, and the FDA panel discussed 10.7% for prostate cancer and 13.6% for stage I cancers.
  • Positive results often lead to invasive tests. In PATHFINDER 2, 72.9% of participants with a positive signal had at least one invasive procedure, including 47.8% of those without a cancer diagnosis.
  • The FDA decision is pending, and it is not clear whether the NHS-Galleri results apply to the version of the test that FDA reviewed.

Signals to watch

  • A peer-reviewed publication of the full NHS-Galleri results.
  • The FDA's final decision on the PMA application, including the age group and the wording of any claims about early detection.
  • A UK National Screening Committee recommendation on multi-cancer tests, and an NHS England decision on rollout.
  • Extended NHS-Galleri follow-up with cancer-death results.
  • Prospective results for the test's cancer signal origin accuracy in routine use, rather than in retrospective analyses of stored samples.

Sources

  1. company announcement
    GRAIL Reports Full Results from NHS-Galleri Trial Demonstrating Substantial Reduction in Stage IV Cancer Diagnoses at 2026 ASCO Annual Meeting
    GRAIL, 30 May 2026.
  2. company announcement
    Landmark NHS-Galleri Trial Demonstrates a Substantial Reduction in Stage IV Cancer Diagnoses, Increased Stage I and II Detection of Deadly Cancers and Four-Fold Higher Cancer Detection Rate
    GRAIL, 19 Feb 2026.
  3. company announcement
    GRAIL Announces FDA Advisory Committee Meeting to Review Premarket Approval Application for the Galleri Multi-Cancer Early Detection Test
    GRAIL, 7 Aug 2026.
  4. news
    FDA Panel Votes in Favor of Galleri Multi-Cancer Early Detection Test
    Andrea Eleazar. Targeted Oncology, 24 Sept 2026.
  5. company announcement
    GRAIL Submits FDA Premarket Approval Application for the Galleri Multi-Cancer Early Detection Test
    GRAIL, 29 Jan 2026.
  6. company announcement
    GRAIL Announces Positive Top-Line Results From The Galleri PATHFINDER 2 Registrational Study
    GRAIL, 18 Jun 2025.
  7. company announcement
    Final Results From PATHFINDER Study of GRAIL's Multi-Cancer Early Detection Blood Test Published in The Lancet
    GRAIL, 5 Oct 2023.
  8. news
    New evidence casts doubt on a much-hyped blood test for early cancer detection
    Margaret McCartney, Deborah Cohen. The BMJ, 8 Aug 2024.
  9. government report
    Assessing the evidence for using multi-cancer early detection tests in screening
    Anne Mackie. UK National Screening Committee, 3 Apr 2023.

Last reviewed 21 Oct 2026.