‘Holy grail’ trialled by NHS could save thousands of lives by detecting cancer before symptoms show

A blood test for those over 50 being tested by the NHS could prevent one in ten cancer deaths in the UK.

The health service is conducting a world-first trial of the test, which aims to detect more than 50 types of cancer before symptoms appear.

Although there are no results yet, the researchers are optimistic that it has ‘huge’ potential. Based on modelling, they believe the ‘Holy Grail’ test could prevent 10 per cent of cancer deaths, of which about 167,000 occur each year in the UK – about 460 per day.

The breakthrough could save about 16,000 lives annually.

The trial’s findings have resulted in hundreds of people already being referred for scans or colonoscopies to the 140,000 volunteers who participated in the trial. It is expected that about half of those referred may develop cancer.

If the test proves successful, the test will be rolled out to a million more people in early 2024, then possibly nationwide.

If the test were made available across the UK and offered to around 18 million adults aged 50 to 79 years, approximately 130,000 more people without symptoms would receive a cancer screening referral each year, assuming that the investigators’ One in a hundred tests positive as expected.

British researchers believe cancer testing – by US company Grail – could be a ‘turning point’ in how the NHS deals with the disease.

There are currently about 3 million urgent cancer referrals annually based on February to February data, so the test would increase referrals by about 5 percent.

The researchers point out that many of these referrals will happen anyway, but at a later date.

The NHS is grappling with a post-Covid backlog of cancer referrals, and data leaked this month showed that more than 10,000 people are waiting for treatment three months after being referred for suspected cancer. But it is expected that this situation may have changed by the time the trial potentially starts.

Professor Peter Sassini, one of the trial’s three principal investigators from King’s College London, said: ‘The potential of this blood test to dramatically cut the number of people dying from cancer is enormous. Of course, if testing is introduced by the NHS, we will see some increase in short-term workloads from slightly higher numbers of referrals for cancer.

‘But in the long run, there should also be many savings for the NHS, such as a reduction in the need for chemotherapy and expensive drugs for advanced cancer.’

The blood test, called the gallery test, picks up pieces of cancer-associated DNA that are shed in the blood, and can suggest which part of the body it came from. It revolutionized the way cancer is detected, as most patients are currently diagnosed only after they develop symptoms.

Based on modelling, they believe the ‘Holy Grail’ test could prevent 10 per cent of cancer deaths, of which there are around 167,000 in the UK each year – about 460 a day.

It will be clear only after the results of the NHS trial are published whether the test can prevent about 10 per cent of all cancer deaths, the modeling shows.

But the test offers hope for hard-to-detect cancers like ovarian and pancreatic, which are usually picked up too late.

People aged 50 to 77 sent invitations to an NHS trial led by Cancer Research UK, King’s College London Cancer Prevention Trial Unit and Grill.

People with signs of cancer in their blood were sent for scans within a target of two weeks, which is expected to apply if they are offered regular blood tests. Researchers are not yet revealing what proportion of people referred to hospital in an NHS trial developed cancer, but previous studies suggest it may be as high as 30 to 70 percent.

By comparison, less than 10 percent of people who are referred to a hospital after being screened for breast or bowel cancer will actually have cancer. NHS testing did not test half of people’s blood samples. Their rates of advanced cancer will be compared to those taking the test. If it’s high enough, it means the test has prevented people from developing an advanced cancer.

The 130,000 referrals using cancer blood tests in the UK are based on people aged 50 to 79 if 70 per cent of them accepted the invitation.

The initial results of the trial will be shared with the NHS in 2024.

Rose Gray from Cancer Research UK said: ‘This type of research is critical to making progress against late-stage cancers and giving more patients the chance of a good outcome.’