Rembert Reemtsen, Brandenburg Technical University of Cottbus, Germany
Continuous optimization of radiotherapy treatment plans
Inverse approaches and, in particular, intensity modulated radiotherapy (IMRT), in combination with the development of new technologies such as multi-leaf collimators, have enabled new potentialities of radiotherapy for cancer treatment. The main mathematical tool needed in this connection is numerical optimization. In this talk we discuss a variety of approaches by continuous optimization, which have been proposed for the computation of optimal beam and beamlet intensities respectively. The discussion includes a nonlinear optimization model for IMRT with biologically motivated goals and an algorithm for its solution, developed by M. Alber from the University Clinics of Tuebingen and the speaker.
At last, the more recent intensity modulated proton therapy (IMPT) is considered. It is shown that the mentioned algorithm is capable to give results in clinical routine within a few minutes of computation time, for IMRT and also in case of the much larger problems for IMPT by the spot-scanning technique.