Published on 22 Mar 2012 Sections

Breakthrough cancer blood test to be made available in UK

Health and Social Care Correspondent

A simple blood test which can detect cancers up to five years earlier than conventional screening is to be made available in the UK for the first time.

Invented and developed by a Professor of Surgery at Nottingham University, the test called Early CDT could revolutionise the way solid tumours such as lung, breast, colon and prostate cancers are detected and treated.

The first of the tests, EarlyCDT-Lung has been available in the United States for two years, and already the results are showing that there is improved prognosis through earlier detection.

Now, alongside the UK roll-out, the Scottish Government has taken the highly unusual step of announcing a massive lung cancer screeing trial using EarlyCDT-Lung. The trial will include 10,000 high-risk smokers, defined as a person having smoked the equivalent of 20 cigarettes a day for more than 20 years. Half will have the blood test and those who are positive will be followd up with CT scans to confirm if lung cancer is present. The other half will be given chest X-rays.

There is currently no screening progamme for lung cancer. If someone has symptoms they may be referred for an X-ray or a CT scan, although they are often not available because they are so expensive.

But, unusually, this is not a trial to prove that CDT works. That has already been established. Instead NHS Scotland will be looking to see if this is a cost-effective way to screen for lung cancer.

Scotland has one of the highest lung cancer rates in the world with about 5,000 patients diagnosed every year. That is 16 per cent of the UK lung cancer total, despite Scotland having only eight per cent of the UK population.

A ‘Detect Cancer Early’ programme is already running and this trial will be piloted as part of that.

The Chief Medical Officer for Scotland Sir Harry Burns said: “The earlier a cancer is diagnosed the greater the chance it can be treated successfully. Currently 85 per cent of patients with lung cancer remain undiagnosed until the disease has reached an advanced stage.”

The cancer specialist who developed the EarlyCDT-Lung technology,Professor John Robertson, of Nottingham University’s Faculty of Medicine and Health Sciences, said that traditionally screening was done by looking for the cancerous cells. “That was like looking for a needle in a haystack. I like to think of this as looking for the haystack rather than the needle,” he said. “We look for the body’s immune response which happens when something is going wrong.”

The test works by replicating the cancer proteins. In the laboratory, seven of these proteins are lined up on a tray and the patient’s blood is passed over them. If there are any auto-antibodies which are the immune systems response to cancerous proteins, they then bind to the proteins or cancer antigens.

A company, Oncimmune Ltd, was set up through Nottingham University to develop and market the test. Its executive chairman Geoffrey Hamilton-Fairley, said up to this point nobody had been able to make this sort of test which searched for an immune response to work.

The significance of such a test is the early detection, its sensitivity and its specificity. Research has shown that different types of cancerous tumours produce different autoantibodies. It is these antibodies which can act as a flag for cancer years before a tumour has developed.

Professor Robertson said: “It is much easier to find the antibodies because there are much higher amounts. Sometimes, in fact, with certain proteins you can’t even find them in the blood but you can find the antibodies. So by taking the proteins and putting them down on a plate in a lab and looking to bind the antibodies from the blood into that we can find the antibodies and say there is something abnormal happening here.”

The test for lung cancer took on more significance last year with a publication of an American trial which showed that screening using CT scans rather than X-rays meant earlier diagnosis and, even more importantly, increased survival rates. Until these results it had largely been thought that even if lung cancers were detected early it made no difference to the death rate.

But CT scans have a high number of false-postive rates. Fifty per cent of high-risk patients screened were called back but in fact did not have cancer. With EarlyCDT-Lung, the false positive rate was just seven per cent.

NHS Scotland is basing its study on an estimate that it will not only be cheaper than using CT scans but that early detection will also save tens of thousands of pounds per patient. One rough estimate is that it costs £50,000 to treat a patient from diagnosis to death. Early detection would mean most people would have surgery and some would not even have to have chemotherapy. This, the believe could save £40,000 for every patient and at the same time improve the death rates by up to 20 per cent. Current survival rates in the UK are as low as five per cent over five years and that has not changed for decades.

The Scottish trial will begin at the end of this year and results are expected in 2014. Oncimmune also hopes to have its tests for breast cancer ready by next years, followed by colon, prostate cancers and others. But they believe that the technology could be of use for all solid tumours.

The test, however, will not be available on the NHS, and patients wanting it will for the moment have to pay privately.

Prof Robertson is hopeful the health services in England, Wales and Northern Ireland will see the value of this form of screening. But he is also pragamatic. “It took us about two years to confirm our ideas were correct and then another 15 years to work out the technology in order to scale it up for wider use.

“It should not have taken as long as that,” he said.