Radiotherapy optimal control in the model of heterogeneous population of swelling sells

Modern notions of clinical radiobiology are applied to construct a mathematical model of radiation therapy, which includes five subpopulations of tumor cells with different growth kinetics and different radiation sensitivity. A “secondary hypoxia effect” is described, connected with increased radiation resistance of the tumor due to redistribution of the cells over the phases of the cycle. A numerical solution of the problem of optimal therapy control is given and the therapeutic benefit of the proposed fractionated irradiation schedules is estimated. Some possible applications of the modeling results are discussed.