Scientist have developed a simple blood test that could detect ten types of cancer years before sufferers fall ill. With an accuracy rate of up to 90 % , it has been hailed as the holy grail' of cancer research.
The test can find early signs of the disease by picking up fragments of DNA that fast-growing cancer cells have released into the blood.
The US authors hope 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 research, said: This is potentially the holy grail of cancer research, to find cancers that are currently hard to cure at an earlier stage when they are easier to cure, and we hope this test 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 %.
The best results were for ovarian cancer diagnosing 90 % of cases and pancreatic cancer, which had 80 % accuracy.
And four out of five liver and gall-bladder cancers were successfully diagnosed.
For blood cancers lymphoma and multiple myeloma, it was 77 and 73 % accurate respectively, while two-thirds of bowel cancer sufferers were correctly diagnosed.
The results for triple-negative breast cancer were 58 % , and the test can also detect lung, oesophageal, and head and neck cancers with more than 50 % 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.
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 is much more sensitive than previous tests.
For cancer there is currently just 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 said: 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 particular 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.'