Radiotherapeutic implications of genetic instability of tumor cells

A mathematical model was used to explore the radiotherapeutic implications of genetic instability. The model included two populations whose different radiosensitivity was represented by different values of alpha parameter of linear quadratic model. It was shown that the presence of a small fraction of mutants may profoundly affect an optimal treatment schedule structure, especially for radiosensitive tumors currently deemed suitable for treatment by hyperfractionation. In some cases, the analysis favors hypofractionation or hybrid schedules composed of hyperfractionated and hypofractionated phases