Analysis of a "phase transition" from tumor growth to latency

A mathematical model, based on the local interaction simulation approach, i s developed in order to allow simulations of the spatiotemporal evolution o f neoplasies. The model consists of a set of rules, which govern the intera ction of cancerous cells among themselves and in competition with other cel l populations for the acquisition of essential nutrients. As a result of sm all variations in the basic parameters, it leads to four different outcomes : indefinite growth, metastasis, latency, and complete regression. In the p resent contribution a detailed analysis of the dormant phase is carried on and the critical parameters for the transition to other phases are computed . Interesting chaotic behaviors can also be observed, with different attrac tors in the parameters space. Interest in the latency phase has been arouse d by therapeutical strategies aiming to reduce a growing tumor to dormancy. The effect of such strategies may be simulated with our approach.