Blood testing people at high risk of lung cancer could reduce the number of deaths, a study has found. University of St Andrews School of Medicine researchers tested biomarkers in the blood of individuals at high risk of developing lung cancer and found the test led to earlier cancer detection and a “major reduction in deaths”.
Lung cancer is often only diagnosed when symptoms emerge and the disease is therefore too advanced for effective treatment. Many have a 10% chance of surviving five more years after the cancer is detected. Biomarkers, such as proteins found in blood or urine, indicate biological processes at work in the body and can reveal changes that may signal lung cancer before symptoms appear, researchers said.
Dr Frank Sullivan, professor of primary care medicine at the University of St Andrews, said of the research published on Wednesday: “This study, along with others using imaging techniques, shows that earlier diagnosis of lung cancer is now possible. That is good news because, if caught early enough, the improved treatments now available have a much higher chance of success.”
Researchers suggested the biomarker test, which looks at autoantibodies in the blood, could be used to identify who needs a subsequent CT scan.
Professor Sullivan told the PA news agency: “The low-dose CT scan over-diagnoses, the blood test misses cancers, whereas if you combine the high sensitivity of one and the high specificity of the other, that might make it a viable option.”
The blood test is also a fairly simple method that “any laboratory anywhere in the world can do fairly cheaply”, he added. The large-scale trial involved 12,208 smokers and ex-smokers who were aged between 50 and 75 years old and at high risk of developing the disease.
One group was screened for abnormal autoantibodies with the EarlyCDT-Lung test every six months for two years. The control group was not tested for autoantibodies and followed standard clinical practice for those at risk of developing the disease.
Both groups were followed for five years. Researchers found that over the five-year period, deaths by any cause and deaths by lung cancer were significantly reduced for those diagnosed within two years of the first EarlyCDT-Lung test.
Of the lung cancer cases caught in that two-year period, there were 34 deaths overall and 29 from lung cancer. Meanwhile, in the control group, there were 56 deaths with 49 from lung cancer. There were therefore 40% fewer deaths from all causes including lung cancer among those who had the EarlyCDT-Lung test, the researchers said.
They added: “After five years, all-cause and lung cancer-specific mortality is significantly reduced in patients tested for autoantibodies and diagnosed with lung cancer within two years of the test. The autoantibodies detected by EarlyCDT-Lung are potentially most valuable for detecting early-stage disease in the first year or two after testing and the cancers detected in this study, in those who tested positive, were mainly early stage when patients were able to benefit from recent advances in the management of early-stage lung cancer.”
Lung cancer may be cheaper to treat if caught at an early stage, they added. The EarlyCDTLung Test measures seven autoantibodies and other biomarker tests including hair and urine are currently being developed across the world. Researcher colleagues from the NHS and the universities of Dundee, Glasgow, Aberdeen, and Nottingham, also worked on the trial and it was published in the Plos One journal.