Epidemiology of lung cancer.

There are few relationships in the epidemiology of cancer between an exposure and disease that are as consistent as those observed between tobacco and lung cancer. The health consequences of tobacco use are not limited to lung cancer; the 1990 Surgeon General's Report described that the use of cigarettes was the leading cause of avoidable mortality in the United States, with about 434,000 preventable deaths per year. Although a majority of the adults in the United States are current or former smokers, smoking cessation and prevention efforts have been successful, although currently about one in four adults still smoke cigarettes. The decline in ever-smoking has reached a plateau in the past few years, however, and rates of teenage smoking have begun to increase. In 1997, smoking rates among high school students in the United States were 32% higher compared with 1991. As noted by Cinciripini et al, adult smokers who quit or die are being replaced by children who smoke. Until recently, lung cancer control efforts primarily have focused on smoking prevention in youth and cessation among adults, with little obvious potential for reducing deaths through early detection. With the recent publication of early results from the Early Lung Cancer Action Project showing remarkably more favorable screening performance compared with chest radiography, the potential to detect lung cancer early and save lives is being revisited. Ultimately, the preferred disease control strategy is the prevention of lung cancer through the elimination of tobacco use altogether, but for the foreseeable future a legacy of decades of tobacco use in a significant proportion of the US population means we are still challenged to develop public health strategies to reduce deaths and suffering from those destined to develop lung cancer.