Drugs used to treat breast cancer may also be useful in tackling lung cancer, according to research in Switzerland.The study, published The Cancer Journal, showed that anti-oestrogens reduced the number of deaths from lung cancer.The authors said the research, if backed up, could have substantial implications for clinical practice.Cancer Research UK warned that large scale clinical trials were needed before any conclusions could be made.Hormones have long been associated with some forms of cancer.Tamoxifen, which cancels out the sex hormone oestrogen, was first used to fight breast cancer more than 40 years ago.Some studies have shown that increasing levels of oestrogen, through hormone replacement therapy, increase the risk of lung cancer.The researchers at the University of Geneva asked if increasing oestrogen increased cancer deaths, would reducing oestrogen have the opposite effect. Preventing deathsThey analysed data on 6,655 women diagnosed with breast cancer between 1980 and 2003. Just under half had been prescribed anti-oestrogens.There was no significant difference in the number of women developing lung cancer, but those on anti-oestrogens did have a lower death rate.Dr Elisabetta Rapiti, who lead the study at the Geneva Cancer Registry, said: "Our results support the hypothesis that there is a hormonal influence on lung cancer, which has been suggested by findings such as the presence of oestrogen and progesterone receptors in a substantial proportion of lung cancers.She said: "If prospective studies confirm our results and find that anti-oestrogen agents improve lung cancer outcomes, this could have substantial implications for clinical practice."Lung cancer is the second most common form of cancer in the UK and is strongly linked with smoking.Oliver Childs, senior science information officer at Cancer Research UK, said: "It's possible that breast cancer drugs like Tamoxifen could also have an effect on lung cancer, but we can't draw firm conclusions from this study alone - the number of women who developed lung cancer was small."Evidence from large-scale clinical trials is needed before we know if these drugs could also be used as new treatments for people with lung cancer."Source: BBC