Modeling of the aging-cancer interface: some thoughts on a complex biological dynamics

Major US demographers predict that, by the year 2010, the United States will have attained zero population growth. They further predict that, by that time, more than half the U.S. population will be over the age of 40. Along with this dynamic change in the underlying age structure of the population comes an increasing body of evidence which supports the correlation between chronological age of the host and incidence of a variety of human cancers. Not only does cancer affect the older age group in a disproportionate manner but, as we have already noted, our nation's number of older individuals is increasing. In 1900, the number of individuals over 65 years of age was 3.1 million. By 2030 this number is expected to reach 55 million. Hence, there will be an increasing need for cancer treatment and cancer care among the older segment of the population. This chapter addresses some of the issues of the modeling and the simulation of the interplay of aging normal tissues and cancer processes. We will illustrate some simply preliminary results and will show how these might be extended to address some of the more complex questions arising in this intriguing interface.