Blood test can predict lung cancer before it is a killer

A BLOOD test has been developed that could save countless lives by improving early detection of lung cancer.

It measures circulating DNA that is shed by cancer cells as they grow and multiply.

Scientists believe it could predict the presence of lowgrade tumours in the lungs long before they become a threat.

Each year around 2,500 people are diagnosed with lung cancer in Ireland, the leading cause of cancer deaths here.

Late diagnosis is one of the main reasons why the disease is so lethal.

By the time it has been detected, the illness has often spread to other parts of the body, making it much more difficult to treat.

The new blood test was developed using mice with a mutant version of the gene KRAS, which triggers cell abnormalities leading to lung cancer.

Mice developing cancerous lung tumours were found to have higher levels of lung cancer DNA in their blood.

The amount of DNA shed by the tumours also correlated with their size seen on CT scans.

‘This is an early study in mice but it is very interesting research’

A closer look at the DNA revealed the presence of the KRAS mutation at a pre-cancerous stage.

Lead scientist Dr Miguel Martins, from the Medical Research Council Toxicology Unit at Cambridge University, said: “This observation is exciting because it suggests that tumour-causing mutations may be detectable in circulating DNA from patients with early-stage cancers or with pre-cancerous tumours.”

The findings are reported in the journal ‘Disease Models and Mechanisms’.

Nick Hopkinson, medical director at the British Lung Foundation, said: “This is an early study in mice, but it is a very interesting area of research.

“In the meantime the most important message is, if you’re a smoker, the best thing you can do to lower your cancer risk is to quit smoking.

“It’s also important not to ignore symptoms like getting out of breath doing things you used to be able to do, or a cough lasting more than a few weeks.”