Radiation Medicine Commons^™

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 …

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 …

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 …

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 …

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 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 …

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 …

Analyzing The Relationship Between Dose And Geometric Agreement Metrics For Auto-Contouring In Head And Neck Normal Tissues, Barbara Marquez, Zachary T Wooten, Ramon M Salazar, Christine B Peterson, David T Fuentes, T J Whitaker, Anuja Jhingran, Julianne Pollard-Larkin, Surendra Prajapati, Beth Beadle, Carlos E Cardenas, Tucker J Netherton, Laurence E Court

Faculty, Staff and Student Publications

This study aimed to determine the relationship between geometric and dosimetric agreement metrics in head and neck (H&N) cancer radiotherapy plans. A total 287 plans were retrospectively analyzed, comparing auto-contoured and clinically used contours using a Dice similarity coefficient (DSC), surface DSC (sDSC), and Hausdorff distance (HD). Organs-at-risk (OARs) with ≥200 cGy dose differences from the clinical contour in terms of Dmax (D0.01cc) and Dmean were further examined against proximity to the planning target volume (PTV). A secondary set of 91 plans from multiple institutions validated these findings. For 4995 contour pairs across 19 OARs, 90% had a DSC, sDSC, …

A Retrospective Quantitative Comparison Of Auto-Planning Vs. Manual-Planning For Large Breast Patients, Olivia R. Smiley

Masters Projects

Breast cancer is the most prevalent cancer among women in the United States, with many patients undergoing whole breast irradiation (WBI) following lumpectomy. Dosimetrists face challenges in planning WBI for patients with large breasts due to issues related to hotspots, dose uniformity, and extended planning times. Auto-planning tools like EZFluence, which use artificial intelligence, offer potential improvements in planning efficiency and dose distribution. This retrospective quantitative study compares auto-planning using EZFluence with manual planning for 10 large breast patients, aiming to reduce hotspots, achieve a more homogeneous dose, minimize doses to organs at risk (OARs), reduce monitor units (MUs), and …