Cigarette smoking and lung cancer: reanalysis of the British doctors' data.

Attention has focused recently on the recessive oncogenesis model, according to which inactivation of both alleles of specific genes leads to cancer. A mathematical formulation of this model was fitted to the lung cancer incidence data from a cohort study among British doctors. The model described the data well. One implication is that age influences lung cancer risk among smokers independently of duration of smoking. A study of dose-response within the framework of the model shows that the data are consistent with various interpretations regarding the relative importance of daily level of smoking and duration of smoking in determining lung cancer risk.