[Social class and bronchial cancer. Quantitative and qualitative aspects of cigarette smoking].

The social class distribution of 400 male lung cancer patients differs significantly from the distribution in 280 controls (more lower-class people among lung cancer patients). Lung cancer patients showed a similar distribution of smokers in all social classes, who had the same tar exposure. Controls showed a similar distribution of smokers in all social classes but a significant difference between the tar exposure of smokers in different social classes. Tar exposure of smokers increases with the decrease of social class, comprising a higher lung cancer risk in the lower social classes, which equals the class distribution of lung cancer patients found in the study.