PET monitoring of hadrontherapy

Abstract

Imaging techniques for in-vivo verification of the ion beam range
and treatment delivery are increasingly receiving a considerable
attention, as they hold the promise to enable full clinical
exploitation of the improved tumour-dose conformality offered
by ion beams. Although promising novel techniques have recently
been proposed and are being investigated in fundamental
pre-clinical research, Positron-Emission-Tomography (PET)
still offers the only technically feasible method for a volumetric
non-invasive verification of the ion treatment during or shortly
after daily dose delivery. This contribution discusses examples
of clinical implementation of PET imaging, with special focus
on the experience in in-beam and offline monitoring of carbon
ion and proton therapy at the GSI Helmholtzzentrum für
Schwerionenforschung in Germany, the Massachusetts General
Hospital in USA, and the Heidelberg Ion Beam Therapy Center
in Germany. In particular, it highlights the encouraging clinical
results but also the encountered major limitations. Finally, it
addresses the most promising ongoing developments aiming
to achieve optimal exploitation of the surrogate PET signal for
in-vivo quality assurance of high precision ion beam therapy.