A blood test to detect cancer is one step closer after scientists developed one that can spot eight types of the disease.
Described as the “Holy Grail”, the newly developed test could revolutionise screening programmes far many deadly cancers.
Although currently still being trialled, hopes are it could eventually see GP’s able to offer patients blood tests to detect the disease even when no symptoms have developed, saving lives through early diagnosis.
Dr Gert Attard, team leader in the Centre for Evolution and Cancer at the Institute of Cancer Research, London, and consultant medical oncologist at the Royal Marsden NHS Foundation Trust, told the BBC: “This is of massive potential.
“I’m enormously excited.
“This is the Holy Grail - a blood test to diagnose cancer without all the other procedures like scans or colonoscopy.”
Scientists at Johns Hopkins University in the US have developed a test that screens for eight common forms of cancer and helps identify the location of the disease.
The test, called CancerSEEK, looks for mutations in 16 genes and evaluates the levels of eight proteins usually released by cancer sufferers.
It was evaluated on 1,005 patients with cancers of the ovary, liver, stomach, pancreas, esophagus, colorectum, lung or breast.
Researchers said its ability to find cancers was successful 70% of the time - and ranged from a high of 98% for ovarian cancer to a low of 33% for breast cancer.
Dr Cristian Tomasetti, from Johns Hopkins University School of Medicine, told the BBC: “This field of early detection is critical, and the results are very exciting.
“I think this can have an enormous impact on cancer mortality.”
He added: “We envision a blood test we could use once a year.”
Professor of oncology Bert Vogelstein said that although the test does not spot every cancer, it identifies many cancers that would likely otherwise go undetected.
However, Dr Richard Marais, Director of the Cancer Research UK Manchester Institute, cautioned that it is still not known how effective the test will be at detecting the disease in people who have no symptoms.
He said: “Detecting cancer early, before the disease has spread is one of the most powerful ways to improve cancer survival and this interesting research is a step towards being able to do this earlier than is currently possible.
“This study only looked at people who were already diagnosed with cancer, so we don’t yet know how effective it would be at picking up the disease in people who don’t have symptoms.
“We now need clinical trials to test its accuracy further as well as more research to work out why the test failed in 30% of patients and whether these tests can be extended to other cancers.
“Hopefully in the future we can develop a blood test such as this that can be used routinely in patients, perhaps once a year, to allow them to know earlier if they have cancer and to get them treated much sooner.”
The next ongoing step is to trial CancerSEEK on people who have not been diagnosed with cancer.
The findings have been published in the journal Science.