Clinical resources for primary care staff

Information for health professionals

The information on this page is designed to support primary care practice staff in areas where the NHS-Galleri trial is taking place. The target audiences are health professionals and supporting organisations participating in the trial.

Wherever possible, practices should direct enquiries relating to the NHS-Galleri trial to the trial website (www.nhs-galleri.org) or the trial team using the contact details below.


Enquiries from the general public:

Email: info@nhs-galleri.org


Participants and people who have received an invitation:

Email: participant_help@nhs-galleri.org

Call: 0800 030 9245


Health professionals:

Email: clinical_help@nhs-galleri.org

Call: 0800 030 9245

The Galleri test looks at DNA in the blood to see if any of it may have come from cancer cells. DNA is the genetic code (a sort of instruction manual) found in cells. Although the Galleri test does not look at the genetic code itself, it looks at the pattern of other markers on the DNA to flag a possible cancer signal and predict where in the body the cancer signal may have come from. However, the signal does not mean that a person definitely has cancer. It just means that they might have cancer, and they will need to have some follow-up tests to check. If a cancer signal is detected, the trial team will contact the participant to organise an appointment at a regional NHS hospital for follow-up tests.

The NHS-Galleri trial is organised by a company called GRAIL Bio UK Ltd. in partnership with NHS England and The Cancer Research UK & King’s College London Cancer Prevention Trials Unit.

  • GRAIL, LLC is a company in the United States (US) that developed the Galleri test. They have also set up a branch in the UK, GRAIL Bio UK Ltd. (GRAIL). They are the main funder and organiser of the NHS-Galleri trial.
  • NHS England is partnering with GRAIL and will provide follow-up tests, hospital care and any treatments related to the trial.
  • The Cancer Research UK & King’s College London Cancer Prevention Trials Unit (KCL-CPTU) are a team of cancer researchers and trial managers based at King’s who will coordinate the trial and analyse the results.

To take part in the NHS-Galleri trial, the person must be:

  • age 50-77 years old;
  • registered at a postcode within a participating Cancer Alliance; and
  • not currently undergoing treatment for cancer or received a cancer diagnosis within the past three years

A selection of people who are eligible to take part will be sent an invitation in the post, including an invitation code unique to them (see section: How are patients invited to take part?). This code is required to register to take part in the trial. In the future it may be possible for people who have not yet received an invitation to take part. Please check the website at https://www.nhs-galleri.org/ to find out more.

The trial is taking place across 8 regions in England known as Cancer Alliances. Cancer Alliances bring together leaders from different hospitals, health and social care organisations, to improve cancer care in local areas. The Cancer Alliances taking part in the NHS-Galleri trial are:

  • Cheshire and Merseyside
  • East of England (North)
  • Greater Manchester
  • Kent and Medway
  • East Midlands
  • West Midlands
  • Northern
  • South East London

Eligible patients (see section: Who can take part in the NHS-Galleri trial?) will be identified by NHS Digital and sent an invitation in the post. NHS Digital is the national custodian of health and care data in England. They collect and hold information from the patient records that health and social care providers maintain. Using this data, NHS Digital can run an electronic search to find patients who meet the eligibility criteria set by the trial. Some patients may be identified and invited by their GP. GRAIL and KCL-CPTU (see section: who is running the NHS-Galleri trial?) will not have access to patient contact details. However, if a patient registers to take part in the trial, they will be asked to share their contact details with the trial team at KCL-CPTU to arrange appointments and receive follow-up information about the study. GRAIL will not have access to patient contact details at any point in the study.

People interested in taking part in the NHS-Galleri trial will make an appointment to attend a mobile clinic near them. At the appointment, they will review information about the trial and have an opportunity to ask questions about taking part. If they are willing to take part, they will sign a consent form, provide a blood sample, and complete surveys about their health. Participants will be asked to do this up to 2 more times, usually with a year between appointments.

Participants in the NHS-Galleri trial will be randomly assigned to either the test or control group. They will not be able to choose which group they are in and will have a 50:50 chance of being assigned to either group.

  • Test (or ‘Intervention’) Group: Half of the people who take part in the trial will be in this group. They will give blood samples and their samples will be tested with the Galleri test at GRAIL’s laboratory in the US as soon as they are received. In this group, a small number of tests are expected to show a cancer signal. Anyone with a ‘Cancer Signal Detected’ will be contacted about their test result and their GP informed. This should happen within 30 days of giving the blood sample.
  • Control Group: Half of the people who take part in the trial will be in this group. They will give blood samples, but their samples will be stored and may be tested in the future. They will not receive results, not even after the trial is finished. A control group is a standard procedure in trials, as it creates a comparison group that the researchers need for their analysis. This comparison group is an essential part of good research.

Participants, and most people involved in running the trial, will not be told which group participants are assigned to. This is because if people know which group they are in, it might alter their health behaviour. This could make the research results less clear or reliable.

When making an appointment for the NHS-Galleri trial, patients will be asked if they need help to access the mobile clinic or if they need an interpreter. Participant information sheets and consent forms will be available in English or alternatively Punjabi, Gujarati, Bengali and Urdu if requested. Participants will be offered a £10 voucher following their appointment as a thank you for their time.

Cancer Alliances will inform GP practices that the trial is taking place in their area. A small number of agreed GP practices/Primary Care Networks (PCN) will send invitations on behalf of the trial. GPs will be notified by the trial team if their patient consents to take part in the trial and if their patient receives a ‘Cancer Signal Detected’ result. The trial team may contact GPs to request additional support if their patient has received a ‘Cancer Signal Detected’ result and has not responded to follow-up invitations (see section: What happens if a patient receives a ‘Cancer Signal Detected’ result?).

If a patient contacts you to discuss whether they should take part, you can advise them that it is their decision to make on the basis of the information provided to them by the trial team- you cannot advise them. Taking part is completely voluntary and if someone does not want to take part, it will not affect the care they receive from the NHS. More information can be found on the NHS-Galleri trial website (www.nhs-galleri.org).

  • If the patient has received an invitation and if they would like to discuss their questions or receive further information, they can email the trial team at participant_help@nhs-galleri.org or telephone 0800 030 9245.
  • If the patient has not received an invitation and would like to discuss their questions or receive further information, they can email the trial team at info@nhs-galleri.org.

If a patient has received an invitation and decides they do not want to take part in the NHS-Galleri trial, no action needs to be taken. The patient will not be contacted or invited to join the trial again.

  • If a patient has not yet received an invitation and has decided they do not want to receive one, they can contact the NHS on 0300 303 5678 or visit the NHS Digital website (https://digital.nhs.uk/services/nhs-digitrials/nhs-galleri-trial).
  • If the patient has previously opted-out of sharing health data for planning and research purposes by submitting a National Data Opt-out, they should not receive an invitation to take part in the NHS-Galleri trial.

All participants will receive a letter to thank them for taking part in the trial and to confirm that their blood sample has been received.

If a participant has not received any results from the trial, no action needs to be taken. This is because most people taking part in the trial will not get a test result.

  • 50% of participants will be in the control group. They will not receive any test results, not even after the trial is finished (see section: what is involved in taking part).
  • 50% of participants will be in the test group. In this group, a small number of tests are expected to show a cancer signal. Anyone with a ‘Cancer Signal Detected’ will be contacted about their result. People in the test group will not be contacted if their blood sample shows no cancer signal (see section: Why are people in the test group not informed if their sample shows no cancer signal?).

Participants who do not receive a test result are still at risk of developing cancer. Participants should continue to attend their NHS screening appointments and inform their GP of any new or unusual symptoms.

If a participant would like to talk to a member of the trial team about their test result, they can email participant_help@nhs-galleri.org or call 0800 030 9245.

People in the test group will not be informed if their blood sample shows no cancer signal. This is because:

  • We do not want to give people false reassurance if no cancer signal was detected. The test will not detect all cases of cancer and we are still collecting information on how well the test works in the NHS.
  • If we tell people their test result, they will know that they are part of the test group. This could alter the way they behave towards their health, which could make the research results less clear or reliable.

A ‘Cancer Signal Detected’ result is not a diagnosis of cancer and follow-up tests are needed to confirm if a participant has cancer. A trial nurse will contact the participant to tell them their result by telephone. If the trial nurse is unable to reach the participant by phone, the participant will be sent a letter requesting they contact the trial team as a matter of urgency. The trial team may contact GPs to request additional support if their patient has received a ‘Cancer Signal Detected’ result and has not responded to follow-up invitations. Trial nurses will refer the participant to their regional NHS hospital via the 2-week wait pathway for follow-up tests to determine if a participant has cancer or not.

Participants with a ‘Cancer Signal Detected’ result will be referred to an NHS hospital for a follow-up tests to look for cancer. No test is perfect and there will be participants with a ‘Cancer Signal Detected’ who will not have a cancer diagnosis confirmed. These participants will be advised (safety-netting) to report any new or changing symptoms to their GP. No additional GP-initiated tests are being recommended unless there are new or changing symptoms. These participants may be anxious, despite having received all the appropriate investigations. All participants with a ‘Cancer Signal Detected’ result who do not have cancer confirmed on follow-up testing will be offered a Galleri test at 12 and 24 months following their first appointment.

Participants should continue to attend their NHS screening appointments and inform their GP of any new or unusual symptoms.

GPs will be informed if their patient receives a ‘Cancer Signal Detected’ result. If further information is required about a particular patient, health professionals can contact the NHS-Galleri trial team at KCL-CPTU by email (clinical_help@nhs-galleri.org) or call 0800 030 9245. Additional information can be found on the NHS-Galleri trial website (https://www.nhs-galleri.org/).

The trial has been reviewed by an NHS ethics committee. This ethics committee has the job of making sure that research trials are well designed and run so that people who take part in the trials are not at an unreasonable risk of harm. The committee has approved the trial and believes that it will be run safely and appropriately. The trial has also been approved by NHS England and NHS Improvement, as part of their work to improve cancer screening for people in England.

Primary Care Information (version 1). Last updated: 19/08/2021