[P137] Joint Estimation of Radiation-Induced Late Toxicity and Cancer Recurrence Risks for Bilateral Breast Cancer after Photon Versus Spot-Scanning Proton Therapy

dictive of clinical acceptable agreement in the target and dose falloff regions.The difference between the performances of ArcCheck Sm and HDm acquisition modes was not clinically relevant.The Arc-Check Sm and EBT3 film PR were significantly correlated between them.An optimal LOA <5% was found between ArcCheck and EBT3 film PR setting the local gamma analysis DTA criterion to 1 mm and the DD% respectively to 4% and 3%.Conclusions.The ArcCheck diode arrays resulted suitable for PsQA at the accuracy level required by SBRT treatments.An optimal LOA <5%, was found between the ArcCheck and the EBT3 film PR with properly selected local gamma criteria.