Pathophysiological Aspects of Cancer Epidemiology

Tumor epidemiology has traditionally used an analytical approach. In order to study the role played by endogenous factors, such as the biological response to tumors, and genetic and physiological factors, a new approach is required. The retroviruses and oncogens illustrate the need to integrate the study of endogenous and exogenous factors in cancer epidemiology. The new ap proach proposed to cancer epidemiology could hopefully have relevant results, for instance in regard to iatrogenic tumors or tumor prevention. If the reason why most secondary tumors are either acute myeloid leukemias or lymphomas can be understood, it may be possible to prevent these iatrogenic tumors now seen in almost 10 per cent of long term survivors.