A therapy system (100) includes an imager (102), a therapy planner (104), and a therapy device (106). The therapy planner (104) includes a therapy prescription apparatus (118) which calculates a desired therapy (D) to be applied to a human patient or other subject. The therapy precription system (118) uses a pathology model (122) and a patient-specific biological parameter history (124) to optimize the applied therapy. WO2008016795A1