NHS-Galleri trial finds fewer diagnoses of the most advanced cancers
Fewer of the most advanced cancers were diagnosed in people screened yearly with a multi-cancer early detection blood test, although no reduction was seen in late-stage cancers overall, the first full results from the NHS-Galleri trial have shown.
The NHS-Galleri trial is a research study to see how well the Galleri® multi-cancer early detection blood test works at a large scale in the NHS. The blood test can detect a ‘signal’ shared by many different types of cancer in a sample of a person’s blood.
The aim of the trial is to see if using the Galleri test alongside existing cancer screening can help to find cancer early. Finding cancer early usually means people have more treatment options and better outcomes.
More than 142,000 volunteers aged 50–77 from eight regions of England took part in the trial. They provided three blood samples over two years, allowing researchers to look at what happened over repeated yearly (annual) rounds of screening.
Impact on cancers diagnosed
There was no difference in the number of people diagnosed with late-stage cancer overall (stage 3 and stage 4 cancers together) between people who had the blood test (test group) and those who did not (control group). This means that the trial did not meet its main goal.
The researchers also looked at other data on what stage cancers were diagnosed at. At least 20% fewer of the most advanced cancers (stage 4) were diagnosed in the second and third round of screening, in the test group compared with the control group.
When researchers looked at 12 types of cancer that tend to grow quickly and are often found at a late stage, stage 4 cancer diagnoses decreased with each year of annual screening. There were 9% fewer stage 4 diagnoses the first time people had the blood test, 22% fewer the second time people had the test and 26% fewer the third time people had the test. Similar reductions were seen when all cancer types were looked at together.
In addition, more early stage cancers were diagnosed in people who had the test. The number of stage 1 and 2 cancers diagnosed was 16% higher overall in people who had the test. This included some cancer types often diagnosed late, such as ovarian, oesophageal, pancreatic and liver cancers.
What these results mean
The results showed fewer diagnoses of the most advanced cancers (stage 4) in people who had the blood test, but no difference in late-stage cancers overall (stage 3 and stage 4 together). Researchers will continue to analyse the data to better understand these findings.
Professor Charles Swanton, Co-Chief Investigator for the NHS-Galleri trial, 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 NHS-Galleri trial tested whether adding the Galleri blood test to NHS screening could reduce the combined number of cancers diagnosed at stage 3 or 4 over three years. The primary goal was not met.”
He added: “However, a pre-specified secondary goal did show a greater than 20% reduction in stage 4 cancers, with the effect strengthening by the third year of screening. 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 noticed that there were more stage 3 cancers in people who had the blood test than in those who did not have the test, especially the first time people had the test (‘prevalent’ screening round). This might help explain why no overall reduction was seen when stage 3 and stage 4 cancers were looked at together.
What else the results showed
The NHS-Galleri trial showed that fewer cancers were detected in an emergency situation, such as in A&E, among people who had the test.
More cancers were found by screening in people who had the test. Adding annual screening with the test to usual NHS screening for breast, colorectal, cervical and high-risk lung cancer detected four times more cancers than NHS screening alone.
People who are diagnosed after a screening test often do better than people diagnosed in other ways. People diagnosed in an emergency situation tend to have worse outcomes. This might be because they are more likely to have more advanced cancer.
The trial showed that the blood test was good at detecting cancer and was safe.
Professor Richard Neal, Co-Chief Investigator for the NHS-Galleri trial, said: “I want to extend my heartfelt thanks to all the people who took part in this landmark trial.
“These first results from the trial have helped us understand more about how the test might help find cancers earlier. They have also helped us learn more about how cancers develop and about this type of blood test.
“These results are just the start of what we will learn from this trial, which is the first and biggest of its kind. The trial and everything that we are discovering from the data would not have been possible without your support.”
What happens next
These first trial results have been shared with researchers at a scientific conference in the United States called the American Society of Clinical Oncology (ASCO) Annual Meeting.
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 researchers have decided to have another look at if the test helped find cancer earlier, using an extra 12 months of data.
Other things the researchers will look at in the future include if people who had a cancer signal detected (‘positive’) test result feel anxious, what effect using the test has on NHS services and if the test is good value for money. In a few years time, the researchers will also look at whether using the test might help reduce cancer deaths.
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.