Women seem to be more vulnerable to tobacco carcinogens. Even when they smoke less, they could more likely fall victim to lung cancer.
Swiss scientists who studied 683 lung cancer patients found that women tended to be younger than men when they developed the disease. This was despite the fact that on average they smoked significantly less than men.
Dr Martin Frueh, from St Gallen Canton Hospital, presented the research at the first European Multidisciplinary Conference in Thoracic Oncology (EMCTO) in Lugano, Switzerland.
Dr Enriqueta Felip, from Val D'Hebron University Hospital in Barcelona, Spain, who co-chaired the meeting, said there was a growing awareness that smoking was riskier for women.
'In the early 1900s lung cancer was reported to be rare in women, but since the 1960s it has progressively reached epidemic proportions, becoming the leading cause of cancer deaths among women in the United States,' she said.
'Lung cancer is not only a man's disease, but women tend to be much more aware of other cancers, such as breast cancer.'
But another study found that women were likely to live longer than men after having lung tumours removed.
Irish researchers led by Dr Bassel Al-Alao, from St James's Hospital, Dublin, checked the progress of 640 patients who had surgery for lung cancer over a 10-year period.
They found that survival after surgery was typically 2.1 years for men and 4.7 years for women.
About 90 per cent of lung cancer cases are caused by smoking. The habit is also thought to contribute to a wide range of other cancers, including those of the mouth, gullet, pancreas, stomach, bladder and kidney.
The meeting also heard that cancer vaccines and targeted therapies were beginning to offer new treatment options for patients with early lung cancer.
One group was trying to identify patients suitable for a vaccine that could be effective in 30 per cent of cases.
Studies have shown that the vaccine can help to prevent cancer re-occurrence after surgery. But it only works in patients with a lung cancer-linked protein called MAGE-A3.
'Personalising therapy is the key strategy for longer and better survival in lung cancer,' said Professor Paris Kosmidis, from Hygeia Hospital in Athens, Greece, who spoke at the meeting.