THE HOLY GRAIL OF CANCER TESTING
Revolutionary analysis can detect disease BEFORE patient develops it
SCIENTISTS have developed a blood test that could detect cancer years before sufferers fall ill.
With an accuracy rate of up to 90 per cent, it has been hailed as the ‘holy grail’ of cancer research. The test can find early signs of ten types of the disease by picking up fragments of DNA that fast-growing cancer cells have released into the blood.
The US authors hope that it will be available for healthy, cancer-free people within five to ten years.
Dr Eric Klein, of Cleveland Clinic’s Taussig Cancer Institute, which led the study, said: ‘This is potentially the holy grail of cancer research, to find cancers that are hard to cure at an earlier stage when they are easier to cure. We hope this could save many lives.
‘Most cancers are detected at a late stage, but this “liquid biopsy” gives us the opportunity to find them months or
years before someone would develop symptoms and be diagnosed.’
The results – to be presented at the American Society of Clinical Oncology conference in Chicago – come from a study of more than 1,600 people, of whom 749 were cancer-free, with no diagnosis, while 878 had been newly diagnosed with the disease.
The blood test that they were given is expected to deliver a result in one to two weeks.
It found early warning signs in the blood for ten types of cancer with an accuracy of more than 50 per cent.
The best results were for ovarian cancer – diagnosing 90 per cent of cases – and pancreatic cancer, which had 80 per cent accuracy.
Four out of five liver and gall-bladder cancers were successfully diagnosed.
For blood cancers lymphoma and multiple myeloma, it was 77 and 73 per cent accurate respectively, while two-thirds of bowel cancer sufferers were correctly diagnosed.
The results for triple-negative breast cancer were 58 per cent, and the test can also detect lung, oesophageal, and head and neck cancers with more than 50 per cent accuracy.
It was less able to pick up stomach, uterine and early-stage low-grade prostate cancer.
Among four cancer-free people who tested positive, two women were diagnosed with ovarian and endometrial cancer months later.
Around 30,000 Scots are diagnosed with cancer every year and that number is predicted to rise to almost 35,000 by 2020.
Lung cancer is the most common cause of cancer death, killing 4,000 a year. Breast cancer is the most common cancer among women, with about 4,700 new cases a year and around 1,000 deaths.
There are around 3,700 new cases of bowel cancer a year in Scotland and 1,600 deaths.
Dr Klein, whose research team also involved Stanford University, said: ‘Potentially this test could be used for everybody, regardless of their family history.
‘It is several steps away, and more research is needed, but it could be given to healthy adults of a certain age, such as those over 40, to see if they have early signs of cancer.’
The test uses whole-genome sequencing. But academics say it
‘Could be used for everybody’
is much more sensitive than previous tests.
For cancer there is at present only one blood test available to diagnose people before they find a lump or initial symptom – the notoriously unreliable PSA test for prostate cancer.
The new test has three parts, testing the whole genome for DNA fragments first, then searching for specific genetic mutations and finally DNA methylation – a process that changes the way genes work when someone has cancer. It is part of a new generation of ‘liquid biopsies’ that have advantages for early detection of cancer over traditional biopsies which remove tissue, such as part of the breast or lung, from the body.
Professor Nicholas Turner, from the Institute of Cancer Research in London, described the findings as ‘really exciting’ and said that they could potentially be used for ‘universal screening’.
He added: ‘Far too many cancers are picked up too late, when it is no longer possible to operate and the chances of survival are slim.
‘The goal is to develop a blood test, such as this one, that can accurately identify cancers in their earliest stages.
‘This test is really exciting but it is likely to be a few years before it is ready for clinical use.’
Simon Stevens, chief executive of NHS England, also welcomed the findings.
He said: ‘As the NHS marks its 70th anniversary, we stand on the cusp of a new era of personalised medicine that will dramatically transform care for cancer and for inherited and rare diseases.
‘In particular, new techniques for precision early diagnosis would unlock enormous survival gains, as well as dramatic productivity benefits in the practice of medicine.’
It comes amid concerns that Scottish patients are missing out on life-saving cancer treatment because of a lack of radiologists.
Earlier this week it emerged that NHS Highland has until August to replace its only remaining interventional radiologist, sparking fears patients may have to travel to other areas to undergo surgery.
NHS Scotland has launched a global recruitment campaign following claims that the country’s radiology service is on the ‘brink of collapse’.
A total of nine Scottish NHS boards, including NHS Highland, hope to recruit 32 radiologists from Western Europe, India, Australia, the United States and Canada.