[Lung cancer: recent epidemiologic data]

The prognosis of lung cancer is still very poor. However, during the last few years a favorable trend has been observed, consisting in the stabilization and even the decrease of incidence rate in Western countries. Besides, the sex-ratio shows a divergent trend, increasing in France and decreasing in the United States where lung cancer nowadays is the first cause of cancer deaths in women. The major risk factor, tobacco smoke, is now well established, qualitatively as well as quantitatively. Other air contaminants, occupational factors and air pollutants, have a lesser responsibility. The intervention of nutritional or genetic factors could explain why smokers are not equally susceptible to tobacco smoke. Screening for lung cancer is, and will be, reconsidered in the light of the results of prospective studies initiated 10 years ago under the auspices of the American Cancer Society.