A simple blood test that can detect cancer before symptoms even start is been being hailed as a major breakthrough which could save thousands of lives.
Likened by scientists to a smoke detector, the test works by detecting changes to red blood cells that occur when cancer is present, rather than the cancer itself.
Costing roughly the same as a standard blood test, it is hoped it could one-day be used to monitor people deemed at high risk of getting the disease.
Early detection boosts the chances of survival in most cancer cases with treatments most effective at targeting the cancer before it spreads.
Scientists believe the discovery, which was unveiled at the British Science Festival in Swansea, could save thousands of lives a year.
It was developed after researchers at Swansea University Medical School studied 300 healthy people, patients with signs of pre-cancer and those with oesophageal cancer.
The test, which only takes a few hours using standard laboratory equipment, detects mutations in proteins on the surface of red blood cells.
Whereas in healthy patients, the average number of mutations is about five per million, in cancer patients there can be 50 to 100 mutants per million.
While they do not have a role in the development of cancer, it is seen as ‘collateral damage’ produced in circulating blood cells as a by-product of a cancer developing internally.
Scientists said the test provides a non-invasive way to monitor high risk patients.
Professor Gareth Jenkins, who led the study, said: ‘The test can be likened to a ”cancer smoke detector” because a smoke detector does not detect the presence of fire in our homes but its by-product, smoke.
‘This test detects cancer, by detecting the ‘smoke’ – mutated blood cells.
‘The old adage of no smoke without fire also applies to ”no cancer without mutation”, as mutation is the main driving force for cancer development.’
Oesophageal cancer, which the test looked at, has particularly poor survival rates as it is often diagnosed late with the average patient only living around a year after diagnosis.
Professor Jenkins said the test would have a ‘massive effect’ if it worked on all types of cancer – and that there were ‘high hopes’ it will.
‘With any cancer, if it is caught early enough and surgically removed, that is the biggest impact you can have on the outcome of a cancer diagnosis,’ he said.
Research is now under way to establish if pancreatic cancer can be traced in the same way.
‘It would be really difficult to think why it would only affect oesophageal cancer,’ he said.
Dr Áine McCarthy, Cancer Research UK’s senior science information officer, said finding new ways to detect cancer early is vital to improve survival rates.
‘Studies like this, which used blood samples to detect background DNA damage as a sign of cancer, are exciting because they could lead to more oesophageal cancers being diagnosed in the early stages.
‘But larger scale studies are needed to confirm the results and show the test is reliable before it can be used in the clinic.’. Health FAQs