Longtime behavior of a class of stochastic tumor-immune systems

This paper focuses on a class of stochastic systems describing tumor-immune dynamics. The underlying systems are given by stochastic differential equations. Our study concentrates on longtime behavior. A sharp threshold-type condition is obtained, which characterizes the dynamic systems, and pinpoints sufficient and nearly necessary conditions for persistence and extinction. Examples and numerical results are provided to illustrate our findings. (c) 2020 Elsevier B.V. All rights reserved.