Radiation Medicine Commons^™

Analysis Of Impulsive Differential Equation Models Of Cell Populations Undergoing Radiation Therapy, Abigail D'Ovidio Long

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Radiation therapy is a mode of treatment which is implemented for approximately 50% of cancer patients. Treatment needs to be able to kill cancer cells, but also do minimal damage to surrounding healthy tissue. We propose two main impulsive differential equation models of radiation therapy to capture the periodic nature of the treatment. These models build off of previous studies using clinical data to ensure biological relevance. The first model incorporates only cancer cell populations, and we provide parameter relationships which theoretically ensure treatment outcomes of cancer eradication, cancer approaching a carrying capacity, and cancer approaching a periodic solution. We …

Novel Cuprotosis-Related Gene Signature: A Prognostic Indicator And Regulator Of The Glioma Immune Microenvironment, Dongming Gao, Youyuan Bao, Wenyin Shi, Lei Li, Liang Gao

Department of Radiation Oncology Faculty Papers

Background: Glioma is a primary malignant brain tumor with a poor prognosis. Glioma-related biomarkers need to be identified to enable the personalized treatment of and predict the prognosis of glioma patients. Cuproptosis is an unusual mechanism of cell death, and is closely associated with disease progression and the immune-microenvironment of the tumor. However, the function of cuproptosis in glioma is still unclear, therefore the aim of this study was to investigate the role of cuproptosis-related genes in gliomas.

Methods: We examined the relationship between cuproptosis and glioma using the clinical and expression data of glioma tumors from The Cancer Genome …

Optimization Processes Of Clinical Chelation-Based Radiopharmaceuticals For Pathway-Directed Targeted Radionuclide Therapy In Oncology, Katsumi Tomiyoshi, Lydia J. Wilson, Firas Mourtada, Jennifer Sims Mourtada, Yuta Namiki, Wataru Kamata, David J. Yang, Tomio Inoue

Department of Radiation Oncology Faculty Papers

Targeted radionuclide therapy (TRT) for internal pathway-directed treatment is a game changer for precision medicine. TRT improves tumor control while minimizing damage to healthy tissue and extends the survival for patients with cancer. The application of theranostic-paired TRT along with cellular phenotype and genotype correlative analysis has the potential for malignant disease management. Chelation chemistry is essential for the development of theranostic-paired radiopharmaceuticals for TRT. Among image-guided TRT,

Isolation, Discrimination, And Feeling “Constant Guilt”: A Mixed-Methods Analysis Of Female Physicians’ Experience With Fertility, Family Planning, And Oncology Careers, Sarah Marion, Shraddha M Dalwadi, Aleksandra Kuczmarska-Haas, Erin F Gillespie, Michelle S Ludwig, Emma B Holliday, Bridgette Thom, Fumiko Chino, Anna Lee

Faculty, Staff and Students Publications

Introduction: Family planning among female physicians is harmed by high risks of infertility, workload burden, poor family leave policies, and gender discrimination. Many women report feeling unsupported in the workplace, despite national policies to protect against unfair treatment.

Methods: This secondary analysis applied a modified version of the rigorous and accelerated data reduction technique to conduct a thematic analysis of comments to an open-ended prompt. Comments were coded by multiple trained researchers then grouped and merged into illustrative themes via qualitative techniques.

Results: Of 1004 responses to the quantitative survey, 162 physicians completed the open-ended prompt. Initial codes (n = …

Conference Report: Review Of Clinical Implementation Of Advanced Quantitative Imaging Techniques For Personalized Radiotherapy, Yevgeniy Vinogradskiy, Houda Bahig, Nicholas Bucknell, Jeffrey Buchsbaum, Hui-Kuo George Shu

Department of Radiation Oncology Faculty Papers

The topic of quantitative imaging in radiation therapy was presented as a "Masterclass" at the 2023 annual meeting of the American Society of Radiation Oncology (ASTRO). Dual-energy computed tomography (CT) and single-positron computed tomography were reviewed in detail as the first portion of the meeting session, with data showing utility in many aspects of radiation oncology including treatment planning and dose response. Positron emission tomography/CT scans evaluating the functional volume of lung tissue so as to provide optimal avoidance of healthy lungs were presented second. Advanced brain imaging was then discussed in the context of different forms of magnetic resonance …

Validation Of An Artificial Intelligence-Based Prognostic Biomarker In Patients With Oligometastatic Castration-Sensitive Prostate Cancer, Jarey H. Wang, Matthew P. Deek, Adrianna A. Mendes, Yang Song, Amol Shetty, Soha Bazyar, Kim Van Der Eecken, Emmalyn Chen, Timothy N. Showalter, Trevor J. Royce, Tamara Todorovic, Huei-Chung Huang, Scott A. Houck, Rikiya Yamashita, Ana P. Kiess, Daniel Y. Song, Tamara Lotan, Theodore Deweese, Luigi Marchionni, Lei Ren, Amit Sawant, Nicole L. Simone, Alejandro Berlin, Cem Onal, Andre Esteva, Felix Y. Feng, Phuoc T. Tran, Philip Sutera, Piet Ost

Department of Radiation Oncology Faculty Papers

BACKGROUND: There is a need for clinically actionable prognostic and predictive tools to guide the management of oligometastatic castration-sensitive prostate cancer (omCSPC).

METHODS: This is a multicenter retrospective study to assess the prognostic and predictive performance of a multimodal artificial intelligence biomarker (MMAI; the ArteraAI Prostate Test) in men with omCSPC (n = 222). The cohort also included 51 patients from the STOMP and ORIOLE phase 2 clinical trials which randomized patients to observation versus metastasis-directed therapy (MDT). MMAI scores were computed from digitized histopathology slides and clinical variables. Overall survival (OS) and time to castration-resistant prostate cancer (TTCRPC) were …

Durable Local Control With Hypofractionated Radiation Therapy For Unresectable Or Metastatic Melanoma, Sydney A Keatts, Aya F Salem, David M Swanson, Ahsan S Farooqi, Andrew J Bishop, Rodabe N Amaria, Jennifer L Mcquade, Isabella C Glitza Oliva, Adi Diab, Roi Weiser, Sarah B Fisher, Ryan P Goepfert, Merrick I Ross, B Ashleigh Guadagnolo, Devarati Mitra

Faculty, Staff and Student Publications

BACKGROUND AND PURPOSE: As patients with advanced melanoma live longer in the context of systemic therapy advancements, better strategies for durable control of bulky tumors are needed. In this study, we evaluated if dose-escalated hypofractionated radiation therapy (HFRT) can provide durable local control and improve tumor-associated symptoms in patients with unresectable or bulky metastatic melanoma for whom stereotactic ablative radiotherapy (RT) approaches are not feasible due to tumor size or location.

MATERIALS AND METHODS: We retrospectively reviewed 49 patients with unresectable or bulky metastatic melanoma who were treated to a total of 53 tumor targets with 12-17 fractions HFRT at …

Personalized Brachytherapy: Applications And Future Directions, Piyush Pathak, Justin J Thomas, Arjit Baghwala, Chengfeng Li, Bin S Teh, Edward B Butler, Andrew M Farach

Faculty, Staff and Students Publications

Brachytherapy offers a highly conformal and adaptive approach to radiation therapy for various oncologic conditions. This review explores the rationale, applications, technological advances, and future directions of personalized brachytherapy. Integration of advanced imaging techniques, 3D-printed applicators, and artificial intelligence are rapidly enhancing brachytherapy delivery and efficiency, while genomic tests and molecular biomarkers are refining patient and dose selection. Emerging research on combining brachytherapy with immunotherapy offers unique synergistic potential, and technologies such as intensity-modulated and shielded brachytherapy applicators present novel opportunities to further optimize dose distributions. Despite these promising advances, the field faces challenges including a need to train more …

Atr Inhibition Radiosensitizes Cells Through Augmented Dna Damage And G2 Cell Cycle Arrest Abrogation, Scott J Bright, Mandira Manandhar, David B Flint, Rishab Kolachina, Mariam Ben Kacem, David Kj Martinus, Broderick X Turner, Ilsa Qureshi, Conor H Mcfadden, Poliana C Marinello, Simona F Shaitelman, Gabriel O Sawakuchi

Faculty, Staff and Student Publications

Ataxia telangiectasia and Rad3-related protein (ATR) is a key DNA damage response protein that facilitates DNA damage repair and regulates cell cycle progression. As such, ATR is an important component of the cellular response to radiation, particularly in cancer cells, which show altered DNA damage response and aberrant cell cycle checkpoints. Therefore, ATR's pharmacological inhibition could be an effective radiosensitization strategy to improve radiotherapy. We assessed the ability of an ATR inhibitor, AZD6738, to sensitize cancer cell lines of various histologic types to photon and proton radiotherapy. We found that radiosensitization took place through persistent DNA damage and abrogated G2 …

Tools And Recommendations For Commissioning And Quality Assurance Of Deformable Image Registration In Radiotherapy, Lando S Bosma, Mohammad Hussein, Michael G Jameson, Soban Asghar, Kristy K Brock, Jamie R Mcclelland, Sara Poeta, Johnson Yuen, Cornel Zachiu, Adam U Yeo

Faculty, Staff and Student Publications

Multiple tools are available for commissioning and quality assurance of deformable image registration (DIR), each with their own advantages and disadvantages in the context of radiotherapy. The selection of appropriate tools should depend on the DIR application with its corresponding available input, desired output, and time requirement. Discussions were hosted by the ESTRO Physics Workshop 2021 on Commissioning and Quality Assurance for DIR in Radiotherapy. A consensus was reached on what requirements are needed for commissioning and quality assurance for different applications, and what combination of tools is associated with this. For commissioning, we recommend the target registration error of …

Source Model Parameters For Beam Commissioning Of Scanning Proton Therapy Treatment Planning System: Multi-Institutional Survey And Analysis, Chih-Wei Chang, Liyong Lin, Lei Dong, Heng Li, Jan Po Schuemann, Jiajian Shen, Xuanfeng Ding

Conference Presentation Abstracts

Purpose: To create a beamline-specific repository of source model parameters and beam commissioning data for scanning proton therapy (PT) treatment planning system (TPS).

Methods: We surveyed 28 PT centers, collecting beam commissioning source model parameters of diverse beamlines from different vendors: Hitachi, IBA, Varian, Mevion. Parameters included (i) beam meterset calibration in protons per MU, (ii) in-air spot size at isocenter in terms of standard deviation in x- (crossline, σ_x) and y- (inline, σ_y) directions, (iii) in-air angular spread at isocenter in x-direction (θ_x) and y-direction (θ_y). We plotted each parameter as …

S6k1 Controls Dna Damage Signaling Modulated By The Mrn Complex To Induce Radioresistance In Lung Cancer, Ali Calderon-Aparicio, Jun He, Nicole L. Simone

Department of Radiation Oncology Faculty Papers

Radiation is a mainstay of lung cancer treatment; however, resistance frequently develops. Identifying novel therapeutic targets to increase radiation sensitivity is crucial. S6K1 is a serine/threonine kinase known to regulate protein translation which is associated with radioresistance, but the mechanisms involved are unknown. We proposed to determine whether S6K1 promotes radioresistance by regulating DNA repair in lung cancer. Colony formation, protein expression and proliferation were assessed. S6K1 was modulated pharmacologically by either PF-4708671 or genetically by Crispr-Cas9. Higher radioresistance levels in lung cancer cells were associated with lower phosphoactivation of MRN complex members, a key activator of radiation-induced DNA repair …

A Dosimetric Comparison Of Treatment Techniques For Stereotactic Body Radiotherapy For Pancreatic Patients, Kameron Lemley

Masters Projects

Stereotactic body radiotherapy (SBRT) is utilized in radiation therapy to deliver ablative radiation doses to tumor volumes while achieving high conformity and minimal dose to surrounding critical structures. This treatment technique allows for faster dose fall-off which allows tighter treatment margins. SBRT for pancreatic cancer has been investigated for its efficacy and has proven to be an effective treatment choice for neoadjuvant radiation therapy. Since pancreatic cancer is extremely aggressive with a high mortality rate, it is important to have a treatment option that can reduce cost and increase convenience for the patient while simultaneously providing a conformal treatment plan. …

Financial Toxicity In Breast Cancer Patients Receiving Regional Nodal Irradiation: Variation By Cancer Subtype, Grace L Smith, Benjamin D Smith, Chi-Fang Wu, Simona F Shaitelman, Mariana Chavez-Macgregor, Rashmi Murthy, Kelsey Kaiser, Kimberly S Ku, Julia J Shi, Sanjay S Shete, Ying-Shiuan Chen, Robert J Volk, Sharon H Giordano, Ya-Chen T Shih, Karen E Hoffman

Faculty, Staff and Student Publications

BACKGROUND: We evaluated sociodemographic and clinical predictors of financial toxicity (FT) among patients with breast cancer with higher risk clinical factors warranting regional nodal irradiation (RNI).

METHODS: Among 183 participants in a clinical trial of conventional vs. hypofractionated treatment with RNI, 125 (68 %) completed a pilot survey of FT measured using the validated Economic Strain and Resilience in Cancer (ENRICh) instrument, scored from 0 (minimal) to 10 (severe) FT. Associations with predictors were evaluated using Pearson correlation coefficients and Kruskal Wallis, Mann-Whitney U, and Jonckheere-Terpstra tests. Predictors of severe FT (ENRICh≥5) were tested using multivariable logistic regression with odds …

Proton Therapy Toxicity Outcomes For Localized Prostate Cancer: Long-Term Results At A Comprehensive Cancer Center, Alan J Sosa, Michael K Rooney, Howard D Thames, Jeremiah W Sanders, David M Swanson, Seungtaek L Choi, Quynh-Nhu Nguyen, Henry Mok, Deborah A Kuban, X Ron Zhu, Shalin Shah, Lauren L Mayo, Karen E Hoffman, Chad Tang, Sean E Mcguire, Narayan Sahoo, Xiaodong Zhang, Andrew K Lee, Thomas J Pugh, Usama Mahmood, John W Davis, Brian F Chapin, Paul Corn, Reena Kudchadker, Noveen Ausat, Steven J Frank

Faculty, Staff and Student Publications

BACKGROUND: Proton therapy (PT) has unique biologic properties with excellent clinical outcomes for the management of localized prostate cancer. Here, we aim to characterize the toxicity of PT for patients with localized prostate cancer and propose mitigation strategies using a large institutional database.

METHODS: We reviewed medical records of 2772 patients with localized prostate cancer treated with definitive PT between May 2006 through January 2020. Disease risk was stratified according to National Comprehensive Cancer Network guidelines as low [LR, n = 640]; favorable-intermediate [F-IR, n = 849]; unfavorable-intermediate [U-IR, n = 851]; high [HR, n = 315]; or very high …

Exploiting The Heavy Chain Glycans For The Improvement Of Radioimmunoconjugates, Cindy Rodriguez

Dissertations, Theses, and Capstone Projects

Radiolabeled antibodies have become indispensable tools in nuclear medicine. However, the natural roles of antibodies within the immune system mean that they have several intrinsic limitations as a platform for radiopharmaceuticals. A handful of recent preclinical studies suggest that binding by FcR and particularly FcyRI can affect the pharmacokinetic profiles of 89Zr-labeled radioimmunoconjugates. Fc receptors (FcR) are responsible for many of the interactions between immunoglobulins (IgG) and immune cells. In biomedicine, this interplay is critical to the activity of several types of immunotherapeutics; however, relatively little is known about how FcRs affect the in vivo performance of radiolabeled antibodies. Antibodies …

Highly Reusable Electrochemical Immunosensor For Ultrasensitive Protein Detection, Kavya L Singampalli, Camille Neal-Harris, Cassian Yee, Jamie S Lin, Peter B Lillehoj

Faculty, Staff and Student Publications

The detection and quantification of protein biomarkers in bodily fluids is important for many clinical applications, including disease diagnosis and health monitoring. Current techniques for ultrasensitive protein detection, such as enzyme-linked immunosorbent assay (ELISA) and electrochemical sensing, involve long incubation times (1.5-3 hr) and rely on single-use sensing electrodes which can be costly and generate excessive waste. This work demonstrates a reusable electrochemical immunosensor employing magnetic nanoparticles (MNPs) and dually labeled gold nanoparticles (AuNPs) for ultrasensitive measurements of protein biomarkers. As proof of concept, this platform was used to detect C-X-C motif chemokine ligand 9 (CXCL9), a biomarker associated with …

Organ-Specific Dosimetry Following Radiopharmaceutical Therapy For Metastatic Prostate Cancer, Frank J. Arturi, Nilanjan Haldar, Shray Jain, Gia Nguyen, Jessie Dinome, Firas Mourtada, Lydia J. Wilson, Phd

Department of Radiation Oncology Posters

Introduction

• Radiopharmaceutical Therapy (RPT) uses radioactive agents to target cancer at the cellular level
• Lu-177 targeting prostate-specific membrane antigen (PSMA), known as 177Lu- PSMA-617, can be used to treat metastatic, castration-resistant prostate cancer (mCRPC)
• 177Lu-PSMA-617 treatments use a standard dose and treatment regimen for all patients
• Patients exhibit different side effects and tumor response during treatment

Clinical And Radiographic Outcomes After Mechanical Thrombectomy In Medium-Vessel Posterior Cerebral Artery Occlusions: Subgroup Analysis From Star, Eyad Almallouhi, Matthew C Findlay, Ilko Maier, Pascal Jabbour, Joon-Tae Kim, Stacey Quintero Wolfe, Ansaar Rai, Robert M Starke, Marios-Nikos Psychogios, Amir Shaban, Nitin Goyal, Shinichi Yoshimura, Hugo Cuellar, Brian Howard, Ali Alawieh, Ali Alaraj, Mohamad Ezzeldin, Daniele G Romano, Omar Tanweer, Justin Mascitelli, Isabel Fragata, Adam Polifka, Fazeel Siddiqui, Joshua Osbun, Roberto Crosa, Charles Matouk, Min S Park, Michael R Levitt, Waleed Brinjikji, Mark Moss, Ergun Daglioglu, Richard Williamson, Pedro Navia, Peter Kan, Reade De Leacy, Shakeel Chowdhry, David J Altschul, Alejandro Spiotta, Ramesh Grandhi

Faculty, Staff and Students Publications

BACKGROUND: Whereas mechanical thrombectomy (MT) has become standard-of-care treatment for patients with salvageable brain tissue after acute stroke caused by large-vessel occlusions, the results of MT in patients with medium-vessel occlusions (MEVOs), particularly in the posterior cerebral artery (PCA), are not well known.

METHODS: Using data from the international Stroke Thrombectomy and Aneurysm Registry (STAR), we assessed presenting characteristics and clinical outcomes for patients who underwent MT for primary occlusions in the P2 PCA segment. As a subanalysis, we compared the PCA MeVO outcomes with STAR's anterior circulation MeVO outcomes, namely middle cerebral artery (MCA) M2 and M3 segments.

RESULTS: …

Retrospective Dosimetric Comparison Of Radiation Therapy Treatment Using Hybrid-Vmat Technique For Esophageal Cancer, Colleen Cozzie

Masters Projects

Abstract

Introduction

Esophageal cancer is the fifth most common gastrointestinal cancer in the United States. As oncology treatment includes radiation as a standard of care, it is vital to examine effective treatment delivery options. Understanding the dosimetric differences between VMAT and hybrid-VMAT can help providers choose the most appropriate care plan for patients undergoing esophageal irradiation. The purpose of this study was to evaluate if VMAT or hybrid-VMAT delivery would be the superior planning method for patients with planning target volumes greater than ten centimeters. Adequately covering the tumor volume while sparing dose to adjacent critical structures is the goal …

Comparative Plan Analysis: Helical Tomotherapy Vs. Linac Vmat For Lower Extremity Sarcomas, Marie E. Dibona

Masters Projects

Abstract

Introduction

Soft tissue sarcomas (STS) affect about 13,500 people annually in the United States, and those in the lower extremities present unique challenges in radiation therapy due to the wide variability in tumor sizes, sometimes exceeding 30cm. Traditional treatment involves C-Arm linear accelerators using Volumetric Modulated Radiation Therapy (VMAT), which provides precise targeting while sparing nearby organs. Helical Tomotherapy (HT) is another option, delivering radiation in a helical pattern with a binary MLC for a uniform dose distribution. However, no studies have compared VMAT and HT for lower extremity sarcomas of different sizes. This study aims to compare these …

Can Simultaneous Integrated Boost Provide Better Dosimetric Coverage Compared To Sequential Boost In Prone Breast Treatment Of Large Breast Volumes?, Kinze Kraft

Masters Projects

Introduction: This study investigates the dosimetric differences between sequential boost (SeB) and simultaneous integrated boost (SIB) techniques in prone breast radiotherapy for patients with large breast volumes, utilizing a 3D-CRT planning technique. Prone positioning in radiotherapy has shown to be effective in reducing heart and lung doses, yet limited research exists to compare overall plan quality between SeB and SIB using this technique. This analysis aims to evaluate whether SIB provides better dosimetric coverage and reduced dose to organs at risk (OARs) compared to SeB in prone breast radiotherapy.

Methods: A retrospective analysis was conducted on data from ten patients …

A Quantitative Investigation Into Isotropic Variations Of Treatment Planning Isocenters To Model Patient Misalignment During Radiation Therapy Delivery And Its Impact On Evaluated Dose Metrics For Hypofractionated Dibh Left Breast Cancer Patients, Mckenzie Gemeiner

Masters Projects

Introduction

This research was conducted for carcinoma of the left breast without nodal involvement using the 3D deep inspiration breath hold (DIBH) treatment technique. Limiting dose to healthy tissues is crucial in radiation treatment planning. The impact of dosimetric uncertainty due to isotropic variations on constraints and goals is often overlooked. This study investigates dose metric differences due to inherent patient misalignment modeled by isotropic variations in treatment planning.

Methods

10 patient subjects were randomly selected with carcinoma of the left breast without nodal involvement, each using the 3D hypofractionated, deep inspiration breath hold (DIBH) technique. All plans had 24 …

A Quantitative Investigation Into The Daily Variation Of Bladder And Rectum Volumes Among Prostate Cancer Patients Receiving Radiation And When It Violates Dose Constraints At Any Given Fraction., Joseph Pape

Masters Projects

When planning radiation therapy treatments for prostate cancer, the bladder and rectum are important organs at risk (OAR). The purpose of this retrospective study was to establish guidelines for bladder and rectal volumes for men receiving hypofractionated radiation therapy to their prostate and seminal vesicles. Ten patients were included in the study and radiation doses to the bladder and rectum were recorded based on the daily change in the OAR volumes. The bladder and rectal volumes were contoured on each patient’s daily treatment CBCT and those volumes were compared to that on the treatment planning CT. The results showed that …

A Comparative Analysis Of Helical Tomotherapy Planning With Active Versus Total Bone Marrow Sparing Using Dual-Energy Computed Tomography, April E. Premo

Masters Projects

Purpose: This study aims to compare helical tomotherapy (HT) plans using active bone marrow (ABM) sparing contouring versus traditional bone marrow (BM) sparing contouring using dual-energy computed tomography (DECT) in the treatment of gynecologic (GYN) cancers. The goal is to evaluate the effects of using ABM contours in optimization on organs at risk (OAR) and planning target volumes (PTVs).

Methods: The study involved creating HT plans for GYN cancer patients, utilizing both ABM and BM contouring techniques. DECT was used to distinguish between active and inactive bone marrow. Dosimetric comparisons were made between BM and ABM sparing plans. Statistical analyses …

Plan Comparison Of Hybrid Dynamic Conformal Arc Therapy (Hdcat) And 3-Dimensional Conformal Radiation Therapy (3dcrt) In Palliative Treatment Of Thoracic Spine Tumors, Maria Juchartz

Masters Projects

Abstract

Introduction

When cancer spreads from its place of origin to a new location, it is termed ‘metastatic’. Metastatic cancer is often not curable, however palliative care can be given. One common method of palliation is in the form of radiation therapy. A common site of metastasis is in the thoracic spine, which has several nearby organs that can make treatment planning difficult. These treatments often consist of three-dimensional conformal radiotherapy methods. The purpose of this study was to compare the traditional 3DCRT techniques to a hybrid dynamic conformal arc technique. HDCAT has been used in previous studies, however none …

Association Between Time From Surgery To Radiation Therapy And Multimodality Treatment Outcomes In Hpv+ Head And Neck Cancer: A Multi-Institutional Cohort Experience, Muneeb Niazi, Ryan Miller, Ryann Kolb, Wenyan Ji, Alicia Lozano, Monica Ahrens, Alexandra Hanlon, Max Pickles, Andrew Song, Voichita Bar-Ad, Neil Hockstein, Sujung Park, Adam Raben, Gaurav Shukla

Department of Radiation Oncology Faculty Papers

Purpose: Oropharyngeal squamous cell cancers (OPSCCs) are traditionally managed with surgery and, if indicated, adjuvant radiation therapy (RT) with or without chemotherapy. NCCN recommends keeping the time from surgery to the start of RT (TSRT) within 6 weeks to avoid possibly compromising patient outcomes. HPV+ OPSCCs behave more favorably than HPV- OPSCCs. We hypothesized that TSRT beyond 6 weeks may not portend poorer outcomes for the former. Methods: We identified nonmetastatic, high-risk HPV+ OPSCCs treated with multimodal therapy at 2 institutions. Prolonged TSRT was defined as >6 weeks and was evaluated for association with recurrence-free survival (RFS). Radiation treatment time …

A Retrospective Quantitative Investigation Into Prostate Radiation Treatment Among Patients With Rectal Gas At Simulation, And How It Affects Planning: A South Florida Context., Soufiane Mansouri

Masters Projects

This study examines the effect of Hounsfield Unit (HU) correction of air in rectal tissue on dose distribution during prostate cancer radiation therapy planning. Ten patients treated between 2023 and 2024, of which received 70 Gray (Gy) in 28 fractions, were retrospectively analyzed. Inclusion criteria included the presence of rectal gas during simulation and noncompliance with pre-simulation preparation instructions. Statistical tests, including a standard t-test and a sign test, were used to compare dose planning without HU correction to planning with HU-corrected rectal gas to tissue, focusing on differences in rectal doses and planned target volume doses. Radiation therapy plans …

Comparison Of Open Thoracoabdominal Repair For Chronic Aortic Dissections And Aneurysms, Ian O Cook, Susan Y Green, Kimberly R Rebello, Qianzi Zhang, Veronica A Glover, Rodrigo Zea-Vera, Marc R Moon, Scott A Lemaire, Joseph S Coselli

Faculty, Staff and Students Publications

Objective: Aortic dissection is common in patients undergoing open surgical repair of thoracoabdominal aortic aneurysms (TAAAs). Most often, dissection is chronic and is associated with progressive aortic dilatation. Because contemporary outcomes in chronic dissection are not clearly understood, we compared patient characteristics and outcomes after open TAAA repair between patients with chronic dissection and those with non-dissection aneurysm.

Methods: We retrospectively analyzed data from 3470 open TAAA repairs performed in a single practice. Operations were for non-dissection aneurysm in 2351 (67.8%) and chronic dissection in 1119 (32.2%). Outcomes included operative mortality and adverse events, a composite variable comprising operative death …

A Clinical Comparison With The Flattening Free Filter Technique For Lung Stereotactic Body Radiotherapy Using Functional Lung Planning, Addison Gucwa

Masters Projects

Abstract

Introduction

Lung cancer remains the leading cause of cancer incidence and mortality worldwide. Advances in stereotactic body radiation therapy have demonstrated survival rates comparable to surgery, however, they come with a higher risk of developing radiation pneumonitis. The aim of this study was to explore the possibility of minimizing the risk of lung toxicities after stereotactic body radiation therapy to lung tumors with the use of functional lung planning and flattening filter free beams.

Materials and Methods

This retrospective study analyzed treatment planning data from ten patients previously treated with SBRT for inoperable lung tumors. Functional lung volumes were …