Medicine and Health Sciences Commons^™

Travel-Time Disparities In Access To Proton Beam Therapy For Cancer Treatment, Todd Burus, Alexander Vanhelene, Michael Rooney, Krystle Lang Kuhs, W. Jay Christian, Christopher Mcnair, Sanjay Mishra, Arnold Paulino, Grace Smith, Steven Frank, Jeremy Warner

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

IMPORTANCE: Proton beam therapy is an emerging radiotherapy treatment for patients with cancer that may produce similar outcomes as traditional photon-based therapy for many cancers while delivering lower amounts of toxic radiation to surrounding tissue. Geographic proximity to a proton facility is a critical component of ensuring equitable access both for indicated diagnoses and ongoing clinical trials.

OBJECTIVE: To characterize the distribution of proton facilities in the US, quantify drive-time access for the population, and investigate the likelihood of long commutes for certain population subgroups.

DESIGN, SETTING, AND PARTICIPANTS: This population-based cross-sectional study analyzed travel times to proton facilities in …

Develop A Novel Beam Orientation Optimization Algorithm For Let (Linear Energy Transfer) Incorporated Impt (Intensity Modulated Proton Therapy) (Imptlet, R Dao, Y Qian, Xiaoqiang Li, H Quan, Xuanfeng Ding, G Liu

Conference Presentation Abstracts

Purpose: To improve the dose and LET distribution in the IMPTLET, we introduce a new optimization algorithm to search for the optimal beam orientation and count through the arc trajectory (BOC-IMPTLET). Methods: We introduce kmeans clustering analysis in the BOC-IMPTLET algorithm by analyzing the distribution of LET in the target from the full arc trajectory. The optimal of cluster count was used as beam count, which was determined based on the SSE (Sum of Square Error) value and the angle of the corresponding centroid of each cluster was used as beam orientation, respectively. The BOC-IMPTLET algorithm was implemented in the …

Investigate The Delivery Efficiency Improvement For Sparc Compared To Impt, Peilin Liu, B A. De Jong, S Chang, Lili Zhao, G Liu, Craig Stevens, Rohan Deraniyagala, E W. Korevaar, J A. Langendijk, Xiaoqiang Li, Xuanfeng Ding

Conference Presentation Abstracts

Purpose: To assess the efficiency improvement of SPArc compared to IMPT in proton clinical operation.Methods: A random clinical operation day at a proton therapy center with a two room system. Aa total of 10 Head & Neck cancer cases treated on Jan 6th, 2021were selected and SPArc plans were generated for all the cases with similar target coverage and dose constraints of organ at risk (OARs). 3% range uncertainties and 3mm setup uncertainties were applied for robust optimization. The log files of clinical IMPT were exported to calculate true treatment delivery time. The machine-specific delivery sequence model was utilized to …

Improving Dose-Response Correlations For Locally Advanced Nsclc Patients Treated With Imrt Or Pspt, Yulun He

Dissertations & Theses (Open Access)

The standard of care for locally advanced non-small cell lung cancer (NSCLC) is concurrent chemo-radiotherapy. Despite recent advancements in radiation delivery methods, the median survival time of NSCLC patients remains below 28 months. Higher tumor dose has been found to increase survival but also a higher rate of radiation pneumonitis (RP) that affects breathing capability. In fear of such toxicity, less-aggressive treatment plans are often clinically preferred, leading to metastasis and recurrence. Therefore, accurate RP prediction is crucial to ensure tumor coverage to improve treatment outcome. Current models have associated RP with increased dose but with limited accuracy as they …

Idiopathic Pulmonary Fibrosis And Lung Cancer: Future Directions And Challenges, Ahmad Abu Qubo, Jamil Numan, Juan Snijder, Maria Padilla, John H.M. Austin, Kathleen M. Capaccione, Monica Pernia, Jean Bustamante, Timothy O’Connor, Mary M. Salvatore

Einstein Health Papers

Idiopathic pulmonary fibrosis (IPF) is a progressive disease of pulmonary scarring. New treatments slow disease progression and allow pulmonary fibrosis patients to live longer. Persistent pulmonary fibrosis increases a patient’s risk of developing lung cancer. Lung cancer in patients with IPF differs from cancers that develop in the non-fibrotic lung. Peripherally located adenocarcinoma is the most frequent cell type in smokers who develop lung cancer, while squamous cell carcinoma is the most frequent in pulmonary fibrosis. Increased fibroblast foci in IPF are associated with more aggressive cancer behaviour and shorter doubling times. Treatment of lung cancer in fibrosis is challenging …

Evaluation And Clinical Implementation Of A Dual-Energy Ct Stopping-Power Ratio Mapping Technique For Proton-Therapy Treatment Planning, Maria Jose Medrano Matamoros

McKelvey School of Engineering Theses & Dissertations

Proton radiotherapy has the potential to treat tumors with better conformal dose distribution than competing modalities when the rapid dose falloff at the end of the proton-beam range is correctly aligned to the edge of the clinical target volume (CTV). However, its clinical potential is dependent on the accurate localization of the Bragg-peak position from predicted stopping-power ratio maps. The method that is most commonly used in today’s clinical practice for predicting stopping-power ratio (SPR) consists of a stoichiometric calibrationtechnique based on single-energy CT (SECT) for direct estimation of patient-specific SPR distribution from vendor-reconstructed Hounsfield Unit (HU) images. Unfortunately, this …

The First Modeling Of The Spot-Scanning Proton Arc(Sparc) Delivery Sequence And Investigating Its Efficiency Improvement, Xuanfeng Ding, Gang Liu, Lewei Zhao, Rohan Deraniyagala, Craig Stevens, Di Yan, Xiaoqiang Li

Conference Presentation Abstracts

Purpose: Introduce an experimental approach to model a precise prototype arc system and quantitatively assess its efficiency improvement in the routine proton clinical operation. Methods: The SPArc delivery sequence model(DSMSPArc) includes two kinds of parameters:(1) mechanical parameters. (2) irradiation parameters. Log files and an independent gantry inclinometer were used to derive the irradiation parameters through a series of test plans. The in-house DSMSPArc was established by fitting both mechanical and irradiation parameters. Eight SPArc plans from different disease sites were used to validate the model’s accuracy. To assess the treatment efficiency improvement, the DSMSPArc was used to simulate the SPArc …

A Direct Machine-Specific Parameters Incorporated Spot-Scanning Proton Arc (Sparc) Algorithm, Gang Liu, Lewei Zhao, Di Yan, Xiaoqiang Li, Xuanfeng Ding

Conference Presentation Abstracts

Purpose: To address the challenges of generating a deliverable and efficient spot-scanning proton arc (SPArc) plan for a proton therapy system. We developed a novel SPArc optimization algorithm (SPArcDMSP) by directly incorporating machinespecific parameters such as mechanical constraints and delivery sequence. Method and Material: A SPArc delivery sequence model (DSMarc) was built based on the machine-specific parameters of the prototype arc delivery system IBA ProteusONEt. The SPArcDMSP resamples and adjusts each control point’s delivery speed based on the DSMarc calculation through the iterative approach (Fig1). Users could set the expected delivery time and gantry max acceleration as a mechanical constraint …

Assess The Interplay Effect Based On The Cyclotron Accelerator Proton Therapy System Machine-Specific Delivery Sequence Model, Lewei Zhao, Gang Liu, J Shen, A Lee, Di Yan, Rohan Deraniyagala, Craig Stevens, Weili Zheng, Xiaoqiang Li, S Tang, Xuanfeng Ding

Conference Presentation Abstracts

No abstract provided.

Toward Online Adaptive Proton Therapy Of Sinonasal Cancer: The Dosimetric Accuracy Of Utilizing Deep-Learning Synthetic Ct From Cbct For Daily Treatment Dose Verification, An Qin, Lewei Zhao, Shupeng Chen, Xiaoqiang Li, Weili Zheng, Di Yan, Rohan Deraniyagala, Xuanfeng Ding

Conference Presentation Abstracts

No abstract provided.

Structure Sparsity Of The Spot Optimization In Proton Arc Therapy, Lewei Zhao

Conference Presentation Abstracts

Radiation therapy is one of the main cancer treatments that uses radiation to kill cancer cells. Proton therapy, or proton radiotherapy, is a type of particle therapy that uses a beam of protons to irradiate tumor volume. Beaumont proton therapy center research group invented the first robust and delivery-efficient spot-scanning proton arc (SPArc) therapy in 2016. Based on our beam modeling platform, we have found that the spot switching time (SSWT) is proportional to spot numbers. We aim to develop a direct mathematical optimization method to reduce the spot numbers for SPArc based on an independent optimization method to reduce …

Modeling Proton Relative Biological Effectiveness Using Monte Carlo Simulations Of Microdosimetry, Mark A. Newpower

Dissertations & Theses (Open Access)

Proton therapy is a radiotherapy modality that can offer a better physical dose distribution when compared to photon radiotherapy by taking advantage of the Bragg peak, a narrow region of rapid energy loss. Proton therapy is also known to offer an enhanced relative biological effectiveness (RBE) compared to photons. In the current clinical standard, RBE is fixed at 1.1 at all points along the proton beam, meaning protons are assumed to require 10% less dose than photons to achieve target coverage and organ at risk (OAR) sparing. However, there is mounting clinical evidence, and a significant number of in vitro …

Evaluation Of Presage® As A 3d Dose Verification Tool In Proton Beams, Mitchell Carroll

Dissertations & Theses (Open Access)

Radiotherapy techniques have advanced and radiation dose plans have become much more complex over the last decade. This is especially true in proton therapy, which involves extremely steep dose gradients as a result of positioning the Bragg peak to cover the volumes to be treated. The Bragg peak can be shifted significantly in the patient as a result of nonuniformities in the tissue composition in its path, which can result in treatment complications. Some traditional dose verification tools used in proton beam commissioning and treatment plan verification are film, TLD, and ionization chambers. Such 0D and 2D dosimeters are incapable …

Magnetically Focused Proton Irradiation Of Small Volume Radiosurgery Targets Using A Triplet Of Quadrupole Magnets, Patrick Mcgee, Grant Mcauley, Andrew Wroe, James M. Slater, Jerry D. Slater

Grant McAuley, PhD

Proton therapy is an advantageous choice for the irradiation of tumors in proximity of critical structures due to rapid dose fall off and high dose deposition at target compared to dose at the surface of the patient (ie, peak-to-entrance dose ratio (P/E)). However, with target fields below 1.0 cm, as often encountered in proton radiosurgery, multiple Coulomb scattering (MCS) broadens proton beams leading to diminished P/E advantages and reduced dose delivery efficiency (DDE). Magnetic focusing tends to counteract MCS and is a promising method to reduce these undesirable effects. The purpose of this research is to investigate the advantages of …

Classification Of Intensity-Modulated Proton Therapy Plans, Louise Gabrielle Lima '19, Alice Liu '19

Student Publications & Research

Proton Radiotherapy

Proton radiotherapy is a form of radiation treatment that uses energized protons to break DNA, leading to cell death and killing cancers.

Magnetically Focused Proton Irradiation Of Small Volume Radiosurgery Targets Using A Triplet Of Quadrupole Magnets, Patrick Mcgee, Grant Mcauley, Andrew Wroe, James M. Slater, Jerry D. Slater

Andrew Wroe, PhD

Proton therapy is an advantageous choice for the irradiation of tumors in proximity of critical structures due to rapid dose fall off and high dose deposition at target compared to dose at the surface of the patient (ie, peak-to-entrance dose ratio (P/E)). However, with target fields below 1.0 cm, as often encountered in proton radiosurgery, multiple Coulomb scattering (MCS) broadens proton beams leading to diminished P/E advantages and reduced dose delivery efficiency (DDE). Magnetic focusing tends to counteract MCS and is a promising method to reduce these undesirable effects. The purpose of this research is to investigate the advantages of …

Advances In Dual-Energy Computed Tomography Imaging Of Radiological Properties, Dong Han

Theses and Dissertations

Dual-energy computed tomography (DECT) has shown great potential in the reduction of uncertainties of proton ranges and low energy photon cross section estimation used in radiation therapy planning. The work presented herein investigated three contributions for advancing DECT applications. 1) A linear and separable two-parameter DECT, the basis vector model (BVM) was used to estimate proton stopping power. Compared to other nonlinear two-parameter models in the literature, the BVM model shows a comparable accuracy achieved for typical human tissues. This model outperforms other nonlinear models in estimations of linear attenuation coefficients. This is the first study to clearly illustrate the …

Magnetically Focused Proton Irradiation Of Small Volume Radiosurgery Targets Using A Triplet Of Quadrupole Magnets, Patrick Mcgee, Grant Mcauley, Andrew Wroe, James M. Slater, Jerry D. Slater

Loma Linda University Student Journal

Proton therapy is an advantageous choice for the irradiation of tumors in proximity of critical structures due to rapid dose fall off and high dose deposition at target compared to dose at the surface of the patient (ie, peak-to-entrance dose ratio (P/E)). However, with target fields below 1.0 cm, as often encountered in proton radiosurgery, multiple Coulomb scattering (MCS) broadens proton beams leading to diminished P/E advantages and reduced dose delivery efficiency (DDE). Magnetic focusing tends to counteract MCS and is a promising method to reduce these undesirable effects. The purpose of this research is to investigate the advantages of …

The Effects Of An Electronic Whiteboard On Transfer Process Efficiency And Staff Satisfaction In An Interdisciplinary Proton Therapy Practice, Tammy Buchanan

Nursing Capstones

No abstract provided.

Assessing The Potential Clinical Impact Of Variable Biological Effectiveness In Proton Radiotherapy, Christopher R. Peeler Ph.D.

Dissertations & Theses (Open Access)

It has long been known that proton radiotherapy has an increased biological effectiveness compared to traditional x-ray radiotherapy. This arises from the clustered nature of DNA damage produced by the energy deposition of protons along their tracks in medium. This effect is currently quantified in clinical settings by assigning protons a relative biological effectiveness (RBE) value of 1.1 corresponding to 10% increased effectiveness compared to photon radiation. Numerous studies have shown, however, that the RBE value of protons is variable and can deviate substantially from 1.1, but experimental data on RBE and clinical evidence of its variability remains limited.

The …

Development And Implementation Of An Anthropomorphic Head & Neck Phantom For The Assessment Of Proton Therapy Treatment Procedures, Daniela Branco

Dissertations & Theses (Open Access)

Proton therapy has been used to treat cancer for more than 50 years, and over the past decade, its use has grown rapidly. One of the main goals of modern radiation therapy is to deliver a high dose to the planning target volume (PTV) with minimal exposure and damage to the surrounding healthy tissue. Protons offer a unique advantage over photon radiotherapy in that they deposit dose over a finite range, in contrast to the more gradual energy deposition of photon and electron beams. At present, 23 proton centers are in operation in the United States and another 13 centers …

Assessment Of Uncertainty In Planning And Dose Delivery Of Proton Therapy In An Iroc- Houston Qa Phantom Due To Variable Ct Technique And Proton Energy, Mattie M. Mcinnis

Dissertations & Theses (Open Access)

As proton therapy increases in popularity, so does the need for effective quality assurance. Proton therapy institutions participating in NCI funded clinical trials rely heavily on the credentialing and auditing services of IROC-H and therefore the process must be well understood. The purpose of this project is to understand the uncertainties in proton therapy treatment planning for the IROC-H proton phantom QA program due to variations in CT technique and proton energy. It was hypothesized that variations in CT technique and proton energy will alter the delivered dose distributions of typical proton treatments by reducing the percent of passing pixels …

Volumetric Scintillation Dosimetry For Scanned Proton Beams, Daniel G. Robertson

Dissertations & Theses (Open Access)

Scanned beam proton therapy is a promising cancer treatment modality which is becoming more widely available with the increasing number of proton radiotherapy centers. Scanned proton beams can produce complex 3D dose distributions, presenting a challenge for adequate quality assurance testing. Because each scanned beam dose measurement requires the delivery of the entire field, multiple measurements can be time consuming. These quality assurance challenges limit the number of patients who can be treated with this modality. The overall objective of this project is to increase the safety and availability of complex proton therapy treatments by developing a fast volumetric scintillation …

Image-Guided Proton Therapy For Online Dose-Evaluation And Adaptive Planning, Joey P. Cheung

Dissertations & Theses (Open Access)

The main advantage for using protons in radiotherapy is their finite range in patients, allowing for potential improved sparing of normal tissues. However, this comes at a cost of increased sensitivity to range uncertainties. Density changes along the beam path will affect the proton range and the resultant dose distribution, making it difficult to estimate the impact of visible anatomic changes to the patient dose distribution. In order to better understand the effect of anatomy change on proton dose, some form of treatment-time verification is required and methods to correct for observed changes would be beneficial. Therefore, this project aims …

Feasibility Of Pulsed Proton Induced Acoustics For 3d Dosimetry, Fahed M. Alsanea

Open Access Theses

Proton therapy has the potential to deposit its energy in tissue with high conformity to the tumor and significantly reduced integral dose to normal tissue compared to conventional radiation, such as x-rays. As a result, local control can be enhanced while reducing side-effects and secondary cancers. This is due to the way charged Particles deposit their energy or dose, where protons form a Bragg peak and establish a well-defined distal edge as a function of depth (range). To date, the dose delivered to a patient from proton therapy remains uncertain, in particular the positioning of the distal edge of the …

Scanned Ion Beam Therapy For Thoracic Tumors, John Gordon Eley

Dissertations & Theses (Open Access)

Although frequently cured of Hodgkin lymphoma, adolescents and young adults can develop radiation induced second cancers. These patients could potentially benefit from scanned ion radiotherapy yet likely would require motion mitigation strategies. In theory, four-dimensional (4D) optimization of ion beam fields for individual motion states of respiration can enable superior sparing of healthy tissue near moving targets, compared to other motion mitigation strategies. Furthermore, carbon-ion therapy can sometimes provide greater relative biological effectiveness (RBE) for cell sterilization in a target but nearly equivalent RBE in tissue upstream of the target, compared to proton therapy. Thus, we expected that for some …

Development And Implementation Of A Dynamic Heterogeneous Proton Equivalent Anthropomorphic Thorax Phantom For The Assessment Of Scanned Proton Beam Therapy, James L. Neihart

Dissertations & Theses (Open Access)

DEVELOPMENT AND IMPLEMENTATION OF A DYNAMIC HETEROGENEOUS PROTON EQUIVALENT ANTHROPOMORPHIC THORAX PHANTOM FOR THE ASSESSMENT OF SCANNED PROTON BEAM THERAPY

by

James Leroy Neihart, B.S.

APPROVED:

______________________________
David Followill, Ph.D.

______________________________
Peter Balter, Ph.D.

______________________________
Narayan Sahoo, Ph.D.

______________________________
Kenneth Hess, Ph.D.

______________________________
Paige Summers, M.S.

APPROVED:

____________________________

Dean, The University of Texas

Graduate School of Biomedical Sciences at Houston

DEVELOPMENT AND IMPLEMENTATION OF A DYNAMIC HETEROGENEOUS PROTON EQUIVALENT ANTHROPOMORPHIC THORAX PHANTOM FOR THE ASSESSMENT OF SCANNED PROTON BEAM THERAPY

A

THESIS

Presented to the Faculty of
The University of Texas
Health Science Center at Houston
and
The University of …

Improving Cervical Cancer Nodal Boost Radiation Therapy By Quantifying Uncertainties And Exploring Advanced Radiation Therapy Modalities, Zhiqian Yu

Dissertations & Theses (Open Access)

Radiation therapy for patients with intact cervical cancer is frequently delivered using primary external beam radiation therapy (EBRT) followed by two fractions of intracavitary brachytherapy (ICBT). Although the tumor is the primary radiation target, controlling microscopic disease in the lymph nodes is just as critical to patient treatment outcome. In patients where gross lymphadenopathy is discovered, an extra EBRT boost course is delivered between the two ICBT fractions. Since the nodal boost is an addendum to primary EBRT and ICBT, the prescription and delivery must be performed considering previously delivered dose. This project aims to address the major issues of …

Evaluation Of Polymer Gel Dosimeters For Measurements Of Dose And Let In Proton Beams, Kevin M. Vredevoogd

Dissertations & Theses (Open Access)

This project assessed the effectiveness of polymer gel dosimeters as tools for measuring the dose deposited by and LET of a proton beam. A total of three BANG® dosimeter formulations were evaluated: BANG®-3-Pro-2 BANGkits™ for dose measurement and two BANG®-3 variants, the LET-Baseline and LET-Meter dosimeters, for LET measurement. All dosimeters were read out using an OCT scanner. The basic characteristics of the BANGkits™ were assessed in a series of photon and electron irradiations. The dose-response relationship was found to be sigmoidal with a threshold for response of approximately 15 cGy. The active region of the dosimeter, the volume in …

Risk Of Second Malignant Neoplasms Following Proton Arc Therapy And Volumetric Modulated Arc Therapy For Prostate Cancer, Laura A. Rechner

Dissertations & Theses (Open Access)

The risk of second malignant neoplasms (SMNs) following prostate radiotherapy is a concern due to the large population of survivors and decreasing age at diagnosis. It is known that parallel-opposed beam proton therapy carries a lower risk than photon IMRT. However, a comparison of SMN risk following proton and photon arc therapies has not previously been reported. The purpose of this study was to predict the ratio of excess relative risk (RRR) of SMN incidence following proton arc therapy to that after volumetric modulated arc therapy (VMAT). Additionally, we investigated the impact of margin size and the effect …