Analysis of virotherapy in solid tumor invasion.

Cancer treatment is an inexact science despite traditional cancer therapies. The traditional cancer treatments have high levels of toxicity and relatively low efficacy. Current research and clinical trials have indicated that virotherapy, a procedure which uses replication-competent viruses to kill cancer cells, has less toxicity and a high efficacy. However, the interaction dynamics of the tumor host, the virus, and the immune response is poorly understood due to its complexity. We present a mathematical analysis of models that study tumor-immune-virus interactions in the form of differential equations with spatial effects. A stability analysis is presented and we obtained analytical traveling wave solutions. Numerical simulations were obtained using fourth order Runge-Kutta and Crank-Nicholson methods. We show that the use of viruses as a cancer treatment can reduce the tumor cell concentration to a very low cancer dormant steady state or possibly deplete all tumor cells in body tissue. The traveling waves indicated an exponential increase and decrease in the cytotoxic-T-lymphocytes (CTLs) density and tumor load in the long term respectively.