Difference between male and female cancer incidence rates: How can it be explained

Age patterns of male and female cancer incidence rate do not look similar. This is because of the biologically based difference in susceptibility to cancer of different sites. This argument, however, does not clarify how age patterns of male and female cancer incidence rate must look like. The analysis of epidemiological data on cancer in different countries and in different years shows that male and female cancer incidence rates intersect around the age of female climacteric. We explain the observed pattern using the difference in ontogenetic components of aging between males and females. The explanation requires a new model of carcinogenesis, which takes this difference into account. Application to data on cancer incidence in Japan (Miyagi prefecture) illustrates the model.