Source: Daily Telegraph
Contact: et.letters@telegraph.co.uk

Exsmokers 'at risk of cancer'
By David Fletcher, Health Correspondent

SMOKING 20 cigarettes a day for 25 years may lead to the development of
lung cancer which cannot be stopped by giving up cigarettes, scientists
said yesterday.

They have found that a biological "switch" a molecular receptor or
gateway develops on the surface of lung cells in people with a lengthy
smoking history. Once it has developed it continues to function, even if
the person stops smoking.

Dr Jill Siegfried, who led the research at the University of Pittsburgh
Cancer Institute, Pennsylvania, said: "Once this switch is turned on, it
appears to be permanent, which may explain in part why longterm exsmokers
who have not had a cigarette in over 25 years are still at high risk for
getting lung cancer."

Knowing when the switch appeared in someone's lung could help doctors give
preventative drugs to avert the final transformation of these cells into
cancer. She said: "Better still, if we can turn off this switch, we might
significantly reduce the odds that an exsmoker will ever get lung cancer."

The study, in the Journal of Respiratory and Critical Care Medicine, showed
that the switch was active in 77 per cent of volunteers who had smoked for
more than 25 years but in only 14.7 per cent of those who had smoked for
less than this.

The antismoking group Action on Smoking and Health said that the research
should not be used as an excuse for longterm smokers not to give up.

A spokesman said: "Stopping smoking reduces the risk of heart disease
almost immediately, even if there is still an increased risk of lung
cancer. It is always worth giving up, whatever your age, but the sooner the
better."

More women are smoking during pregnancy because they do not believe it is a
danger to themselves or their baby, a study by the Health Education
Authority said.

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