[Estimation of cancer latency using data from a case-control study with time-related factors--estimated latency for consumption of alcohol and tobacco in relation to gastric cancer].

As a practical application of theory, the susceptible exposure age and latency distribution of consumption of alcohol and tobacco in relation to stomach cancer is discussed. It was revealed that, in univariate, estimation of the susceptible exposure age of alcohol and tobacco were 15-50 years and 35-50 years. The estimated latency were 35 years and 15 years. Those of accumulative period and preneoplastic period were 30 and 10 years. In a multivariate analysis, the latency for alcohol consumption was changed to 20 years as the incubation time in preneoplastic period was prolonged by 5 years due to consumption of vegetables. This could give a theoretical interpretation of second line cancer prevention.