GATE as a GEANT4-based Monte Carlo platform for the evaluation of proton pencil beam scanning treatment plans

International audienceIn the field of hadron therapy, active scanning delivery systems take full advantage of ion beams to best conform the dose to the tumor shape and to spare surrounding healthy tissues. However, it is also a challenging technique for quality assurance. This paper presents a generic method for the evaluation of proton treatment planning systems (TPS) with the GATE/GEANT4 Monte Carlo (MC) code. It presents various comparisons in homogeneous and heterogeneous configurations between a commercial TPS, MC simulations and measurements. The study is concluded by the evaluation of a prostate cancer treatment plan. Several sources of discrepancies were illustrated and the limits of the TPS analytical algorithms were evidenced in heterogeneous geometries. The possibility of using GATE for clinical validation purposes has been demonstrated. GATE is a convenient tool for imaging and dosimetric applications in medical physics, with new capabilities for active scanning treatment plan simulation