A mathematical model for the effect of obesity on cancer growth and on the immune system response

Several experimental studies have found that obesity is a risk factor for different types of cancer. In this work we present a mathematical model of cancer tumor growth that takes into account the immune system response and the effects of obesity on the organism with cancer. This model consists of four ordinary differential equations with a logistic equation for the growth of the amount of fat stored. We analyze the stability of the equilibria obtained using parameter values reported in the literature. Our simplified model succeeds to reproduce different scenarios reported in clinical studies, such as, the negative effect of obesity on the cancer patient and the anticancer effect of a low caloric diet. (C) 2015 Elsevier Inc. All rights reserved.