Attributable causes of lung cancer incidence and mortality in China.

The aims of our study were to estimate the contribution of known lung cancer risk factors, and provide evidence to support the National Cancer Prevention and Control Program in China. We calculated the proportion of lung cancer attributable to specific risk factors. Data on exposure prevalence were from meta-analyses and large-scale national surveys of representative samples of the Chinese population. Data on relative risks were from meta-analyses and large-scale prospective studies. Lung cancer mortality and incidence were taken from the Third National Death Survey and from cancer registries in China. We estimated that in China 285 304 lung cancer deaths and 327 465 cases were attributable to smoking, involuntary smoking (women only), occupational exposure, indoor radon, and low fruit intake in 2005. The proportion of lung cancer deaths attributable to smoking, involuntary smoking among non-smoking women, occupational exposure, indoor radon and low fruit intake was 56.9%, 11.1%, 9.5%, 0.2% and 12.4%, respectively. About 41% of lung cancer mortality and incidence in women was caused by risk factors in our study. However, over half of lung cancer deaths and cases among women were not attributable to known risk factors. It is necessary to conduct large-scale studies to identify additional risk factors of lung cancer in non-smoking women.