Overview
- The randomized trial of about 142,000 people aged 50 to 77 tested annual Galleri screening against standard NHS care and did not meet its pre‑specified primary endpoint of reducing combined stage‑3 and stage‑4 diagnoses.
- Presented at the American Society of Clinical Oncology in May 2026, researchers reported a more than 20% fall in stage‑4 cancers but an overall increase in stage‑3 diagnoses, suggesting some cancers were detected earlier without clear net downstaging.
- Galleri is a multi‑cancer early detection blood test by GRAIL that looks for fragments of tumour DNA to screen for over 50 cancer types from one blood draw, and the trial cost about £150 million to run across the NHS.
- GRAIL’s chief medical officer said the results alone will not secure NHS approval and NHS England leaders said they will review the full trial data before deciding how, or whether, to use the test.
- Independent experts cautioned that only long trials measuring survival can prove a mortality benefit, and they warned shorter stage‑shift measures can raise referrals and strain services without clear evidence of lives saved.