Neoplasia withstands cancer.

A theory is presented which regards cancer as a systemic disease caused by carcinogens. The organism protects itself by mobilizing its stem cell pool which proliferates in form of a neoplasm to withstand the deterioration of systemic cancer. These ideas are illustrated in form of a mathematical model which reproduces the known epidemiological functions such as: Age specific cancer incidence, prevalence, mortality and cancer survival. Their shap supports the theory and is consistent with the above assumptions. The model may be utilized further for the estimation of cancer prevalence and the degree of interaction between chronic systemic diseases and cancer. Since these features of the model are independent of the above assumptions, it may be applied to cancer epidemiology as such.