Exciting results from blood test for 50 cancers

A blood test for more than 50 types of cancer could help speed up diagnosis, a new study suggests.

Results from a trial in North America show the test was able to identify a wide range of cancers, three-quarters of which are not covered by any form of screening program.

More than half of cancers were detected at an early stage, where they are easier to treat and potentially curable.

The Galleri test, carried out by the American pharmaceutical company Grail, can detect cancerous DNA fragments detached from a tumor and circulating in the blood.

The trial followed 25,000 adults from the United States and Canada for a year.

Nearly one in 100 people tested had a positive result and in 62% of them the cancer was later confirmed.

The test correctly ruled out cancer in more than 99% of people who tested negative.

Combined with breast, bowel and cervical screening, it has increased the overall number of cancers detected sevenfold.

Above all, three quarters of the cancers detected concerned cancers for which there was no screening program, such as those of the ovary, liver, stomach, bladder and pancreas.

The blood test correctly identified the origin of the cancer in 9 out of 10 cases.

These impressive results suggest that blood testing could eventually play a major role in the early diagnosis of cancer.

Scientists not involved in the research say more evidence is needed to demonstrate whether blood tests reduce cancer deaths.

The main results are due to be published at the European Society for Medical Oncology congress in Berlin, but full details have not yet been published in a peer-reviewed journal.

Much will depend on the results of a three-year trial involving 140,000 NHS patients in England, which will be published next year.

The NHS has previously said that if the results were conclusive it would expand testing to a further million people.

Lead researcher Dr. Nima Nabavizadeh, associate professor of radiologic medicine at Oregon Health and Science University, said the latest data shows the test could “fundamentally change our approach to cancer screening, helping to detect many types of cancer earlier, when the chances of treatment success, or even cure, are greatest.”

But Clare Turnbull, professor of translational cancer genetics at the Institute of Cancer Research in London, said: “Data from randomized studies, with mortality as an endpoint, will be absolutely essential to determine whether apparently earlier detection by Galleri translates into mortality benefits. »

Sir Harpal Kumar, president of Biopharma at Grail, told the BBC: “We think these results are very compelling. The opportunity before us is that we can find many more cancers – and many of the most aggressive cancers – at a much earlier stage when we have more effective and potentially curative treatments.

Naser Turabi from Cancer Research UK said: “More research is needed to avoid overdiagnosing cancers which may not have caused harm. The UK National Testing Committee will play a vital role in reviewing the evidence and determining whether these tests should be adopted by the NHS. »