Lung cancer in nonsmokers more common in women

NEW YORK, Feb 14 (Reuters) The findings of a new study confirm that lung cancer among nonsmokers is more common in women than in men.

Lung cancer is the leading cause of cancer death in the US, and research in the patterns of lung cancer in those who have never smoked is ''an important public health priority,'' Dr Heather A Wakelee, from Stanford University School of Medicine in California, and colleagues emphasize in their report in the Journal of Clinical Oncology.

Smoking remains the main cause of lung cancer, the investigators note. As such, few studies have looked at the occurrence of this malignancy among nonsmokers.

Wakelee's team assessed the epidemiology of nonsmokers with lung cancer. Epidemiology refers to the study of factors that affect illness in various populations -- and is used to make decisions about interventions in the interest of public health and disease prevention.

The investigators analyzed data from six large prospective studies: the Nurses' Health Study, the Health Professionals Follow-up Study, the California Teachers Study, the Multiethnic Cohort Study, the Swedish Lung Cancer Register in the Uppsala/Orebro region, and the First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study.

In nonsmokers between 40 and 79 years of age, the incidence of lung cancer was 14.4 to 20.8 per 100,000 persons per year for women and 4.8 to 13.7 per 100,000 persons per year for men.

The results also indicate that the lung cancers that affect never smokers are different from those typically seen in smokers. For example, cancers in patients who never smoked respond differently to drugs and are more likely to have a different appearance.

The cause of lung cancer in nonsmokers is not completely understood, but researchers expect second-hand smoke exposure probably plays a role.

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