Proton TherapyProtonsRadiotherapy Planning, Computer-AssistedRadiotherapy DosageRadiotherapy, Intensity-ModulatedOrgans at RiskRadiometryCraniospinal IrradiationNeutronsChordomaMonte Carlo MethodProton PumpsPhotonsRadiotherapy, ConformalRadiotherapy, High-EnergyRelative Biological EffectivenessRadiation InjuriesUncertaintyFour-Dimensional Computed TomographyScattering, RadiationRadiation DosageTreatment OutcomeRadiation OncologyPhantoms, ImagingFibromatosis, AbdominalRadiotherapyRadiotherapy, Computer-AssistedOutcome Assessment (Health Care)Proton Pump InhibitorsTomography, X-Ray ComputedDose-Response Relationship, RadiationTumor BurdenProstatic NeoplasmsAlgorithmsRetrospective StudiesPregnancy OutcomeNeoplasms, Radiation-InducedMagnetic Resonance SpectroscopyReproducibility of ResultsMovementSpineHydrogen-Ion ConcentrationComputer SimulationNeoplasms, Second Primary