First results announced from trial of blood test for cancer

The first full results have been announced from research looking at whether a blood test can help the NHS to detect cancer early.

The results from the NHS-Galleri trial – whose Co-Chief Investigator is UCLH medical oncologist Professor Charles Swanton – showed that, although the trial's main goal was not met, fewer of the most advanced (stage 4) cancers were diagnosed in the later rounds of annual screening among those who had the Galleri® multi-cancer early detection test.

More than 142,000 volunteers aged 50-77 from across England took part in the trial of the blood test, which can detect a ‘signal’ in a sample of blood shared by many different types of cancer.

The main aim was to see whether adding the Galleri blood test to NHS screening could reduce the number of cancers diagnosed at stage 3 and 4, across three years of annual screening.

The results, announced on 30 May by the company GRAIL who developed the test, showed there was no difference in the overall number of stage 3 and stage 4 cancers diagnosed, which means the main aim of the study was not met.

However, a secondary objective of the study was to look at stage 4 cancers alone. This secondary objective was planned before the study began. The study found that stage 4 cancers were lower overall in people who had the test, with at least 20% fewer stage 4 cancers diagnosed in the second and third round of screening. This pattern is consistent with the test detecting some cancers earlier, before they would otherwise have reached stage 4, although longer follow-up, including mortality data, is needed to confirm a genuine benefit.

Professor Swanton, who is supported by the NIHR UCLH Biomedical Research Centre, said:

“As a lung cancer doctor, I see the clinical importance of diagnosing cancer at an earlier stage, when treatment is more likely to be curative. The stage 4 reduction is clinically meaningful because for many cancers there is a real gulf in outlook between a stage 4 diagnosis and one caught earlier. The hope is that for more patients the conversation can be about treating cancer with curative intent rather than managing it palliatively.”

The researchers will continue to analyse the data from the trial over the coming months and years. More results will be reported in the future.

The NHS and other health organisations will review the results of the trial in detail to understand how this type of test could be used in the future.