Abstract

In the treatment of cancer, proton therapy offers a more conformal treatment than conventional radiotherapy owing to the fact that the ionization density is highest within a narrow range of depth in tissue, i.e., the Bragg peak. However, taking full advantage of the Bragg peak has so far not been possible due to range uncertainties that come about as a result of anatomical changes during the course of treatment, organ motion, patient positioning and setup errors as well as inherent uncertainties in estimating the tissue stopping power. These uncertainties warrant the development of so-called range monitoring techniques that ideally enable adaptation of the treatment in case of range errors. Yet, there is still no range monitoring system that is used in routine clinical proton therapy practice. To address this problem, we have recently formed the NOVO (NeutrOn and gamma-ray imaging for real-time range VerificatiOn and image guidance in particle therapy) collaboration to develop a compact detector array (NOVCoDA) consisting of optically segmented, bar-shaped organic scintillator elements with dual-ended light readout. The NOV CoDA is to enable simultaneous detection and imaging of secondary fast neutrons and prompt gamma-rays that are produced abundantly in nuclear collisions during treatment. In this talk, I will give an overview of the recent results of experimental campaigns exploring suitable organic scintillator materials via characterisation of their physical properties as well as providing an overview of the results of a Monte Carlo modelling study that explored the feasibility of the proposed approach to detect clinically relevant range shifts of 1-2 mm and its capabilities of identifying relevant treatment deviations via a clinical example case.   On behalf of the NOVO collaboration.