COMPUTER PROCEDURES IN 3D RADIOTHERAPY TR EATMENT PLANNING

The aim of 3D radiotherapy treatment planning is to match the dose as closely as possible to the target volume, thus avoiding side effects i n healthy tissue and radiosensitive organs at risk. A virtual radiothe rapy simulator designed for the definition of treatment parameters and the analysis of precalculated dose distributions enables iterative op timization of treatment plans. Methods: VOXELPLAN is a software packag e for 3D radiotherapy treatment planning developed at the German Cance r Research Center; it consists of user interfaces for image segmentati on, virtual therapy simulation, dose calculation, plan evaluation and patient documentation. It is written in C and FORTRAN and runs on VAXs tation 4000, IBM RS/6000 and DEC ALPHA hardware. Results: Since 1990 a pilot installation of VOXELPLAN has been applied in clinical routine at the Center and at the University Clinic for Radiology, Heidelberg. Treatment for more than 1500 patients has been planned and carried out using the system, proving its technical and organizational applicabil ity. Conclusions: We expect better acceptance and further disseminatio n of the techniques described, conformation therapy as well as (after its technical realization) inverse planning, from continuous optimizat ion of the planning process.