Abstract

In 1946 particle physicist Robert Wilson was the first to point out that high energy protons might be a useful tool in radiotherapy. The characteristics of the interaction of energetic ions with matter indeed allow a dose distribution that is much more conformal with the target (malignant tissue to be irradiated) than can be achieved with X-rays, i.e. the dose integral to inevitably co-irradiated normal tissue is significantly lower. Normal tissue complications are in radiotherapy with photons often constraining the tumor dose and thereby treatment success rate. Nevertheless translating the physical advantage of radiotherapy with protons (and other ions) into clinical benefit has shown to be rather difficult for various reasons, which will be discussed, and is yet to be completed. The planned clinical facility for radiotherapy with protons in Groningen and the associated comprehensive research programme will be shortly presented.