Michelle Böck: Challenges in Adaptive Radiation Therapy

The goal in radiation therapy is to maximize tumor-damage while limiting toxic effects of radiation on nearby healthy tissue and organs. Typically, optimization problems are formulated and solved to determine best compromise between the involved anatomical structures which constitutes the treatment plan. Once such a treatment plan is obtained, the total planned dose is split into a series of predetermined equal-dosage fractions delivered daily so that healthy cells can recover between sessions. Therefore, commercial treatment planning software solutions are based on static-deterministic optimization methods, and thus, these solutions cannot adapt to uncertain interfractional anatomical variations, such as the tumor’s response due to radiation-induced damage, taking place in the course of the treatment. Some uncertainties can be accounted for by robust optimization during the planning stage. If interfractional anatomical variations lead to non-negligible deviations from the prescribed dose distribution, the original plan has to be adapted. The approach to adaptive radiation therapy can vary in sophistication and costs. The dynamic nature of the problem raises the demand for interdisciplinary thinking and for combing concepts of robust optimization, control theory and radiation biology modelling.

How the challenges in adaptive radiation therapy can be confronted is the subject of the upcoming PhD seminar. Join the battle against cancer!