Test may spot smoking cancer risk

Scientists may be able to tell a smoker whether he or she is at particularly high risk of developing lung cancer.
Of the hundreds of millions worldwide who smoke tobacco, only a relatively small proportion will go on to die from lung cancer.

Israeli scientists have found that smokers who lack a particular body chemical are five times more likely to develop the disease.

The study, published in the Journal of the National Cancer Institute, adds to evidence of a lung cancer smoking gene.

The chemical is called OGG, and appears to have a role in repairing DNA within cells.

It is thought to be damage to DNA caused by tobacco smoke which triggers the growth of tumours as cells fail to divide and die normally.

Screening call

A team of scientists from the Weizmann Institute of Science led by Professor Zvi Livneh, looked at levels of active OGG in the blood of 68 patients with lung cancer, and 68 healthy patients.

They found that those in the lowest third of OGG activity were 4.8 times more likely to be found in the lung cancer group.

Their suggestion is that the low levels of OGG might contribute to the development of lung cancer in some cases.

Professor Livneh said: "If so, then screening for smokers with low OGG activity, followed by smoking cessation in those individuals, may lead to a decrease in the incidence of lung cancer."

If OGG does emerge as pivotal in preventing lung cancer in patients whose lungs are damaged by smoke, then it is possible that the lower levels of the chemical in some patients are due to a different genetic makeup.

In that case, it might be possible to test for the gene, or simply test the blood for OGG levels.

There is no proof that the low levels of OGG might be contributing to the lung cancer - the research cannot exclude the possibility that having lung cancer itself might interfere with the production of the chemical, or the amount to be found in blood tests.

Mike Unger, the chief executive of the UK's Roy Castle Lung Foundation, said that he did not believe that the test would deter smokers from putting their lives at risk.

"Smokers already know that they are at risk of dying from smoking-related diseases, and it doesn't stop them."

He said the focus should be on early detection of the disease, as 90% of those diagnosed with lung cancer die, usually within months.

Article Source: http://www.bbc.co.uk