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Principal Investigator: Daniel Ellis Hyer
Organization: UNIVERSITY OF IOWA
Fiscal Year: 2024
Award: $395,858
Funding agency: National Cancer Institute
Abstract/Summary
Proton arc therapy has lagged behind photon arc therapy, which is now commonplace in the clinic, due mostly
to slow proton energy switching times which make treatment durations impractical. Fast energy modulation
systems are now clinically available, and, by applying delivery optimization tools that intelligently change beam
energy as the gantry rotates, proton arc therapy is on the verge of becoming a clinical reality that can improve
plan delivery speed and robustness to range uncertainties relative to conventional fixed field proton therapy.
Without dynamic lateral beam collimation, however, proton arc therapy tumor dose conformity will be inferior to
fixed field collimated proton therapy plans. This is a major problem especially for brain and head and neck
cancer patients whose normal tissues could be spared significant radiation dose using beam collimation. The
long-term goal is to develop the next generation of pencil beam scanning (PBS) proton therapy delivery
systems that maximize the achievable tumor dose conformity, robustness, and delivery speed. The overall
objective of this proposal is to develop dynamically collimated arc-based PBS by expanding the dynamic
collimation system (DCS) technology developed in the first part of this R37 proposal, providing the capability
for rapid, tumor-conformal delivery of dose distributions that are more robust to uncertainties in Bragg Peak
position placement than those delivered with fixed field proton therapy. The rationale for this project is that
superior treatment plans will result from the combination of energy-specific collimation and rotational arc
delivery than either of the individual technologies, thus improving the quality of care of proton therapy. Guided
by strong preliminary data from our in-silico treatment planning studies and constructed DCS prototype,
development of collimated proton arc therapy will be carried out by pursuing three specific aims: 1) develop
arc-based treatment planning and delivery methods for dynamically collimated proton therapy, 2) enhance the
clinical DCS prototype to perform proton arc treatments, and 3) adapt existing treatment verification
methodologies for quality assurance. Under specific aim 1, established multi-field treatment planning
techniques, both dose calculation and optimization, will be extended to include the optimization of trimmer and
energy sequencing for the case of a rotating gantry. Under specific aim 2, real-time feedback mechanisms will
be incorporated to monitor and synchronize gantry angle to the sequencing of the high-speed trimmer blades.
Under specific aim 3, experimental and computational techniques will be developed and demonstrated to
enable successful commissioning of dynamic collimated proton arc therapy. The research proposed in this
application is innovative because it represents a new combination of two promising and synergistic
technologies: dynamic collimation and proton arc therapy. This contribution is expected to be significant since
the two technologies together can preserve conformity improvements gained by collimated PBS while adding
the robustness and delivery speed benefits achievable with arc therapy, improving treatment outcomes.
Terms: <Acceleration><Acute Radiation Syndrome><Air><Algorithms><Area><Benchmarking><Best Practice Analysis><Body Tissues><Brain><Brain Neoplasia><Brain Neoplasms><Brain Nervous System><Brain Tumors><Cancer Patient><Cancers><Childhood><Clinic><Clinical><Collimation><Collimator><Computational Technique><Data><Development><Devices><Distal><Dose><Encephalon><Ensure><Equipment><Feedback><Foundations><Goals><H+ element><HNC patient><Head and Neck Neoplasms><Hydrogen Ions><Individual><Industrialization><Inferior><Intercept><Ions><Lateral><Malignant Neoplasms><Malignant Tumor><Marketing><Measurement><Measures><Mechanics><Methodology><Methods><Mission><Modeling><Monitor><Motion><Normal Tissue><Normal tissue morphology><Outcome><Parents><Patients><Photons><Planning Methodology><Planning Technic><Planning Techniques><Plant Leaves><Position><Positioning Attribute><Predisposition><Protons><Public Health><QOC><QOL><Quality of Care><Quality of life><Radiation Dose><Radiation Dose Unit><Radiation Toxicity><Radiation therapy><Radiotherapeutics><Radiotherapy><Radiotoxicity><Research><Risk Reduction><Rotation><Scanning><Speed><Spottings><Surface><Susceptibility><System><Techniques><Technology><Testing><Time><Tissues><Translating><Treatment Efficacy><Treatment Period><Treatment outcome><Uncertainty><Validation><Work><benchmark><brain tissue><care delivery><clinical care><commercialization><cost><cost effective><design><designing><developmental><doubt><fighting><head and neck cancer patient><head and neck tumor><improved><in silico><innovate><innovation><innovative><intervention efficacy><leaf><malignancy><mechanic><mechanical><neoplasm/cancer><new technology><next generation><novel technologies><parent><pediatric><preservation><proton beam><proton therapy><prototype><quality assurance><radiation poisoning><radiation treatment><reduce risk><reduce risks><reduce that risk><reduce the risk><reduce these risks><reduces risk><reduces the risk><reducing risk><reducing the risk><risk-reducing><side effect><technology platform><technology system><therapeutic efficacy><therapy efficacy><tool><treatment days><treatment duration><treatment planning><treatment with radiation><tumor><tumors in the brain><validations>