A Decision Support System for Radiation Therapy Treatment Planning

This paper reports on the use of an interactive decision support system to generate treatment plans for external beam radiation therapy. When evaluating treatment plans, radiation therapists are often faced with situations where overdose of healthy organs or underdose of the tumour cannot be avoided. Current treatment planning software incorporate trial-and-error methods to change treatment parameters and re-optimise in order to generate a better treatment plan. However, this process is not only inefficient, but also does not yield information on how radiation doses depend on the structure site and the planning parameters. Here a multi-criteria-based optimisation model is presented, which is used to calculate a large number of efficient treatment plans. These are stored in a database and accessed for evaluation by the decision support system Carina. The navigation among those solutions and the information that is provided to guide the user in this process are described. Of special importance is sensitivity analysis, which extracts dose dependence information for the tumour and healthy organs from the efficient treatment plans. As a result, plan quality is improved by finding advantageous trade-offs in competing treatment plans. Additionally, the common trial-and-error process is avoided and effectiveness in treatment planning is increased.