Radiation Medicine Commons^™

Harnessing Uncertainty In Radiotherapy Auto-Segmentation Quality Assurance, Kareem A Wahid, Jaakko Sahlsten, Joel Jaskari, Michael J Dohopolski, Kimmo Kaski, Renjie He, Enrico Glerean, Benjamin H Kann, Antti Mäkitie, Clifton D Fuller, Mohamed A Naser, David Fuentes

Faculty, Staff and Student Publications

One of the key contributions of this study is the reappropriation of standard DL outputs as a quality indicator to identify cases that clinicians should review further. The authors achieve this by applying an empirically derived threshold to the softmax output of their DL network, computing the mean of the thresholded score map (termed the HiS metric), and correlating it with standard geometric quality indices. When juxtaposed with a mean entropy — a commonly used measure of model output uncertainty — HiS consistently demonstrated a stronger correlation with the geometric indices, suggesting its superior ability to stratify cases needing additional …

Reporting Quality Of Endoscopic Colorectal Cancer Screening Randomized Controlled Trials: Adherence To Recommendations And Interventions, Fouad Jaber, Khalid Ahmed, Osama Hamid, Willie Mohammed Johnson, Saqr Alsakarneh, Abubaker O Abdalla, Yazan Abboud, Mouhand Mohamed, Dushyant Singh Dahiya, Shifa Umar, Mohamed Abdallah, Mohammad Bilal, Aasma Shaukat

Faculty, Staff and Student Publications

BACKGROUND AND AIMS: In 2013, the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) steering group published recommendations to standardize reporting quality in randomized controlled trials (RCTs). We aim to assess adherence to SPIRIT reporting guidelines in RCTs on endoscopic colorectal cancer (CRC) screening and participants' adherence to trial protocols.

METHODS: We searched databases for RCTs evaluating flexible sigmoidoscopy or colonoscopy for CRC screening published in English language through September 2023. Each eligible study was evaluated using the 8 core SPIRIT statement areas, totaling 51 points. Each item received 1 point if it met the criteria and 0 points if …

Clinical Acceptability Of Automatically Generated Lymph Node Levels And Structures Of Deglutition And Mastication For Head And Neck Radiation Therapy, Sean Maroongroge, Abdallah Sr Mohamed, Callistus Nguyen, Jean Guma De La Vega, Steven J Frank, Adam S Garden, Brandon G Gunn, Anna Lee, Lauren Mayo, Amy Moreno, William H Morrison, Jack Phan, Michael T Spiotto, Laurence E Court, Clifton D Fuller, David I Rosenthal, Tucker J Netherton

Faculty, Staff and Student Publications

BACKGROUND AND PURPOSE: Auto-contouring of complex anatomy in computed tomography (CT) scans is a highly anticipated solution to many problems in radiotherapy. In this study, artificial intelligence (AI)-based auto-contouring models were clinically validated for lymph node levels and structures of swallowing and chewing in the head and neck.

MATERIALS AND METHODS: CT scans of 145 head and neck radiotherapy patients were retrospectively curated. One cohort (n = 47) was used to analyze seven lymph node levels and the other (n = 98) used to analyze 17 swallowing and chewing structures. Separate nnUnet models were trained and validated using the separate …

Improving Radiotherapy In Immunosuppressive Microenvironments By Targeting Complement Receptor C5ar1, Callum Beach, David Maclean, Dominika Majorova, Stavros Melemenidis, Dhanya K Nambiar, Ryan K Kim, Gabriel N Valbuena, Silvia Guglietta, Carsten Krieg, Mahnaz Darvish-Damavandi, Tatsuya Suwa, Alistair Easton, Lily Vs Hillson, Ashley K Mcculloch, Ross K Mcmahon, Kathryn Pennel, Joanne Edwards, Sean M O'Cathail, Campbell S Roxburgh, Enric Domingo, Eui Jung Moon, Dadi Jiang, Yanyan Jiang, Qingyang Zhang, Albert C Koong, Trent M Woodruff, Edward E Graves, Tim Maughan, Simon Ja Buczacki, Manuel Stucki, Quynh-Thu Le, Simon J Leedham, Amato J Giaccia, Monica M Olcina

Faculty, Staff and Student Publications

An immunosuppressive microenvironment causes poor tumor T cell infiltration and is associated with reduced patient overall survival in colorectal cancer. How to improve treatment responses in these tumors is still a challenge. Using an integrated screening approach to identify cancer-specific vulnerabilities, we identified complement receptor C5aR1 as a druggable target, which when inhibited improved radiotherapy, even in tumors displaying immunosuppressive features and poor CD8+ T cell infiltration. While C5aR1 is well-known for its role in the immune compartment, we found that C5aR1 is also robustly expressed on malignant epithelial cells, highlighting potential tumor cell-specific functions. C5aR1 targeting resulted in increased …

Targeted Gene Expression Profiling Predicts Meningioma Outcomes And Radiotherapy Responses, William C Chen, Abrar Choudhury, Mark W Youngblood, Mei-Yin C Polley, Calixto-Hope G Lucas, Kanish Mirchia, Sybren L N Maas, Abigail K Suwala, Minhee Won, James C Bayley, Akdes S Harmanci, Arif O Harmanci, Tiemo J Klisch, Minh P Nguyen, Harish N Vasudevan, Kathleen Mccortney, Theresa J Yu, Varun Bhave, Tai-Chung Lam, Jenny Kan-Suen Pu, Lai-Fung Li, Gilberto Ka-Kit Leung, Jason W Chan, Haley K Perlow, Joshua D Palmer, Christine Haberler, Anna S Berghoff, Matthias Preusser, Theodore P Nicolaides, Christian Mawrin, Sameer Agnihotri, Adam Resnick, Brian R Rood, Jessica Chew, Jacob S Young, Lauren Boreta, Steve E Braunstein, Jessica Schulte, Nicholas Butowski, Sandro Santagata, David Spetzler, Nancy Ann Oberheim Bush, Javier E Villanueva-Meyer, James P Chandler, David A Solomon, C Leland Rogers, Stephanie L Pugh, Minesh P Mehta, Penny K Sneed, Mitchel S Berger, Craig M Horbinski, Michael W Mcdermott, Arie Perry, Wenya Linda Bi, Akash J Patel, Felix Sahm, Stephen T Magill, David R Raleigh

Faculty, Staff and Student Publications

Surgery is the mainstay of treatment for meningioma, the most common primary intracranial tumor, but improvements in meningioma risk stratification are needed and indications for postoperative radiotherapy are controversial. Here we develop a targeted gene expression biomarker that predicts meningioma outcomes and radiotherapy responses. Using a discovery cohort of 173 meningiomas, we developed a 34-gene expression risk score and performed clinical and analytical validation of this biomarker on independent meningiomas from 12 institutions across 3 continents (N = 1,856), including 103 meningiomas from a prospective clinical trial. The gene expression biomarker improved discrimination of outcomes compared with all other systems …

Operational Ontology For Oncology (O3): A Professional Society-Based, Multistakeholder, Consensus-Driven Informatics Standard Supporting Clinical And Research Use Of Real-World Data From Patients Treated For Cancer, Charles S Mayo, Mary U Feng, Kristy K Brock, Randi Kudner, Peter Balter, Jeffrey C Buchsbaum, Amanda Caissie, Elizabeth Covington, Emily C Daugherty, Andre L Dekker, Clifton D Fuller, Anneka L Hallstrom, David S Hong, Julian C Hong, Sophia C Kamran, Eva Katsoulakis, John Kildea, Andra V Krauze, Jon J Kruse, Tod Mcnutt, Michelle Mierzwa, Amy Moreno, Jatinder R Palta, Richard Popple, Thomas G Purdie, Susan Richardson, Gregory C Sharp, Shiraishi Satomi, Lawrence R Tarbox, Aradhana M Venkatesan, Alon Witztum, Kelly E Woods, Yuan Yao, Keyvan Farahani, Sanjay Aneja, Peter E Gabriel, Lubomire Hadjiiski, Dan Ruan, Jeffrey H Siewerdsen, Steven Bratt, Michelle Casagni, Su Chen, John C Christodouleas, Anthony Didonato, James Hayman, Rishhab Kapoor, Saul Kravitz, Sharon Sebastian, Martin Von Siebenthal, Walter Bosch, Coen Hurkmans, Sue S Yom, Ying Xiao

Faculty, Staff and Student Publications

PURPOSE: The ongoing lack of data standardization severely undermines the potential for automated learning from the vast amount of information routinely archived in electronic health records (EHRs), radiation oncology information systems, treatment planning systems, and other cancer care and outcomes databases. We sought to create a standardized ontology for clinical data, social determinants of health, and other radiation oncology concepts and interrelationships.

METHODS AND MATERIALS: The American Association of Physicists in Medicine's Big Data Science Committee was initiated in July 2019 to explore common ground from the stakeholders' collective experience of issues that typically compromise the formation of large inter- …

Systematic Review Of Genetic Polymorphisms Associated With Acute Pain Induced By Radiotherapy For Head And Neck Cancers, Vivian Salama, Yimin Geng, Jillian Rigert, Clifton D Fuller, Sanjay Shete, Amy C Moreno

Faculty, Staff and Student Publications

BACKGROUND/OBJECTIVE: Pain is the most common acute symptom following radiation therapy (RT) for head and neck cancer (HNC). The multifactorial origin of RT-induced pain makes it highly challenging to manage. Multiple studies were conducted to identify genetic variants associated with cancer pain, however few of them focused on RT-induced acute pain. In this review, we summarize the potential mechanisms of acute pain after RT in HNC and identify genetic variants associated with RT-induced acute pain and relevant acute toxicities.

METHODS: A comprehensive search of Ovid Medline, EMBASE and Web of Science databases using terms including "Variants", "Polymorphisms", "Radiotherapy", "Acute pain", …

Primary Tumor Site For Localized Merkel Cell Carcinoma Drives Different Management Strategies Without Impacting Oncologic Outcomes, Samuel Cass, Brandon Cope, Andrew J Bishop, Yi-Ju Chiang, B Ashleigh Guadagnolo, Ahsan Farooqi, William Morrison, Russell G Witt, Riyad N H Seervai, Adam S Garden, Clifton D Fuller, Ryan P Goepfert, Merrick Ross, Jeffrey E Gershenwald, Michael Wong, Phyu P Aung, Emily Z Keung, Devarati Mitra

Faculty, Staff and Student Publications

BACKGROUND AND PURPOSE: Clinically localized Merkel cell carcinoma (MCC) has been associated with high rates of disease relapse. This study examines how primary tumor anatomic site drives patterns of care and outcomes in a large cohort treated in the contemporary era.

MATERIALS AND METHODS: Patterns of care and associated outcomes were evaluated for clinically Stage I-II MCC patients treated at our institution with adjuvant radiation therapy (RT) to the primary site and/or regional nodal basin as a component of their curative intent therapy between 2014-2021.

RESULTS: Of 80 patients who met inclusion criteria, the primary tumor anatomic site was head …

Widefield Imaging Of Rapid Pan-Cortical Voltage Dynamics With An Indicator Evolved For One-Photon Microscopy, Xiaoyu Lu, Yunmiao Wang, Zhuohe Liu, Yueyang Gou, Dieter Jaeger, François St-Pierre

Faculty, Staff and Students Publications

Widefield imaging with genetically encoded voltage indicators (GEVIs) is a promising approach for understanding the role of large cortical networks in the neural coding of behavior. However, the limited performance of current GEVIs restricts their deployment for single-trial imaging of rapid neuronal voltage dynamics. Here, we developed a high-throughput platform to screen for GEVIs that combine fast kinetics with high brightness, sensitivity, and photostability under widefield one-photon illumination. Rounds of directed evolution produced JEDI-1P, a green-emitting fluorescent indicator with enhanced performance across all metrics. Next, we optimized a neonatal intracerebroventricular delivery method to achieve cost-effective and wide-spread JEDI-1P expression in …

Automated Contouring And Statistical Process Control For Plan Quality In A Breast Clinical Trial, Hana Baroudi, Callistus I Huy Minh Nguyen, Sean Maroongroge, Benjamin D Smith, Joshua S Niedzielski, Simona F Shaitelman, Adam Melancon, Sanjay Shete, Thomas J Whitaker, Melissa P Mitchell, Isidora Yvonne Arzu, Jack Duryea, Soleil Hernandez, Daniel El Basha, Raymond Mumme, Tucker Netherton, Karen Hoffman, Laurence Court

Faculty, Staff and Student Publications

BACKGROUND AND PURPOSE: Automatic review of breast plan quality for clinical trials is time-consuming and has some unique challenges due to the lack of target contours for some planning techniques. We propose using an auto-contouring model and statistical process control to independently assess planning consistency in retrospective data from a breast radiotherapy clinical trial.

MATERIALS AND METHODS: A deep learning auto-contouring model was created and tested quantitatively and qualitatively on 104 post-lumpectomy patients' computed tomography images (nnUNet; train/test: 80/20). The auto-contouring model was then applied to 127 patients enrolled in a clinical trial. Statistical process control was used to assess …

Quantitative Longitudinal Mapping Of Radiation-Treated Prostate Cancer Using Mr Fingerprinting With Radial Acquisition And Subspace Reconstruction, Victoria Y Yu, Ricardo Otazo, Can Wu, Ergys Subashi, Manuel Baumann, Peter Koken, Mariya Doneva, Peter Mazurkewitz, Daniel Shasha, Michael Zelefsky, Laura Cervino, Ouri Cohen

Faculty, Staff and Student Publications

MR fingerprinting (MRF) enables fast multiparametric quantitative imaging with a single acquisition and has been shown to improve diagnosis of prostate cancer. However, most prostate MRF studies were performed with spiral acquisitions that are sensitive to B0 inhomogeneities and consequent blurring. In this work, a radial MRF acquisition with a novel subspace reconstruction technique was developed to enable fast T1/T2 mapping in the prostate in under 4 min. The subspace reconstruction exploits the extensive temporal correlations in the MRF dictionary to pre-compute a low dimensional space for the solution and thus reduce the number of radial spokes to accelerate the …

Immunotherapy Targeting Different Immune Compartments In Combination With Radiation Therapy Induces Regression Of Resistant Tumors, Nils-Petter Rudqvist, Maud Charpentier, Claire Lhuillier, Erik Wennerberg, Sheila Spada, Caroline Sheridan, Xi Kathy Zhou, Tuo Zhang, Silvia C Formenti, Jennifer S Sims, Alicia Alonso, Sandra Demaria

Faculty, Staff and Student Publications

Radiation therapy (RT) increases tumor response to CTLA-4 inhibition (CTLA4i) in mice and in some patients, yet deep responses are rare. To identify rational combinations of immunotherapy to improve responses we use models of triple negative breast cancer highly resistant to immunotherapy in female mice. We find that CTLA4i promotes the expansion of CD4+ T helper cells, whereas RT enhances T cell clonality and enriches for CD8+ T cells with an exhausted phenotype. Combination therapy decreases regulatory CD4+ T cells and increases effector memory, early activation and precursor exhausted CD8+ T cells. A combined gene signature comprising these three CD8+ …

Advances In The Radiological Evaluation Of And Theranostics For Glioblastoma, Grayson W Hooper, Shehbaz Ansari, Jason M Johnson, Daniel T Ginat

Faculty, Staff and Student Publications

Imaging is essential for evaluating patients with glioblastoma. Traditionally a multimodality undertaking, CT, including CT cerebral blood profusion, PET/CT with traditional fluorine-18 fluorodeoxyglucose (18F-FDG), and MRI have been the mainstays for diagnosis and post-therapeutic assessment. However, recent advances in these modalities, in league with the emerging fields of radiomics and theranostics, may prove helpful in improving diagnostic accuracy and treating the disease.

Multi-Parametric Mri For Radiotherapy Simulation, Tian Li, Jihong Wang, Yingli Yang, Carri K Glide-Hurst, Ning Wen, Jing Cai

Faculty, Staff and Student Publications

Magnetic resonance imaging (MRI) has become an important imaging modality in the field of radiotherapy (RT) in the past decade, especially with the development of various novel MRI and image-guidance techniques. In this review article, we will describe recent developments and discuss the applications of multi-parametric MRI (mpMRI) in RT simulation. In this review, mpMRI refers to a general and loose definition which includes various multi-contrast MRI techniques. Specifically, we will focus on the implementation, challenges, and future directions of mpMRI techniques for RT simulation.

Gwas-Identified Telomere Length Associated Genetic Variants Predict Risk Of Recurrence Of Hpv-Positive Oropharyngeal Cancer After Definitive Radiotherapy, Peng Sun, Peng Wei, Hongliang Liu, Jia Wu, Neil D Gross, Andrew G Sikora, Qingyi Wei, Sanjay Shete, Mark E Zafereo, Jisheng Liu, Guojun Li

Faculty, Staff and Student Publications

Background: Lymphocyte telomere length (LTL)-related genetic variants may modulate LTL and affect recurrence of squamous cell carcinoma of the oropharynx (SCCOP).

Methods: A total of 1013 patients with incident SCCOP were recruited and genotyped for 16 genome-wide association study (GWAS)-identified TL-related polymorphisms. Of these patients, 489 had tumour HPV16 status determination. Univariate and multivariate analyses were performed to evaluate associations.

Findings: Of the 16 TL-related polymorphisms, four were significantly associated with LTL: rs1920116, rs3027234, rs6772228, and rs11125529, and the patients with putatively favourable genotypes had approximately 1.5-3 times the likelihood of shorter LTL compared with patients with the corresponding risk …

Predicting Severity Of Radiation Induced Lymphopenia In Individual Proton Therapy Patients For Varying Dose Rate And Fractionation Using Dynamic 4-Dimensional Blood Flow Simulations, Lucas Mccullum, Jungwook Shin, Stella Xing, Chris Beekman, Jan Schuemann, Theodore Hong, Dan Duda, Radhe Mohan, Steven H Lin, Camilo M Correa-Alfonso, Sean Domal, Julia Withrow, Wesley Bolch, Harald Paganetti, Clemens Grassberger

Faculty, Staff and Student Publications

PURPOSE: Radiation-induced lymphopenia has gained attention recently as the result of its correlation with survival in a range of indications, particularly when combining radiation therapy (RT) with immunotherapy. The purpose of this study is to use a dynamic blood circulation model combined with observed lymphocyte depletion in patients to derive the in vivo radiosensitivity of circulating lymphocytes and study the effect of RT delivery parameters.

METHODS AND MATERIALS: We assembled a cohort of 17 patients with hepatocellular carcinoma treated with proton RT alone in 15 fractions (fx) using conventional dose rates (beam-on time [BOT], 120 seconds) for whom weekly absolute …

Longitudinal Diffusion And Volumetric Kinetics Of Head And Neck Cancer Magnetic Resonance On A 15 T Mr-Linear Accelerator Hybrid System: A Prospective R-Ideal Stage 2a Imaging Biomarker Characterization/Pre-Qualification Study, Joint Head And Neck Radiation Therapy-Mri Development Cooperative, Mr-Linac Consortium Head And Neck Tumor Site Group

Faculty, Staff and Student Publications

Objectives: We aim to characterize the serial quantitative apparent diffusion coefficient (ADC) changes of the target disease volume using diffusion-weighted imaging (DWI) acquired weekly during radiation therapy (RT) on a 1.5 T MR-Linac and correlate these changes with tumor response and oncologic outcomes for head and neck squamous cell carcinoma (HNSCC) patients as part of a programmatic R-IDEAL biomarker characterization effort.

Methods:Thirty patients with HNSCC who received curative-intent RT at MD Anderson Cancer Center, were included. Baseline and weekly MRI were obtained, and various ADC parameters were extracted from the regions of interest (ROIs). Baseline and weekly ADC parameters were …

Addressing The Global Expertise Gap In Radiation Oncology: The Radiation Planning Assistant, Laurence Court, Ajay Aggarwal, Hester Burger, Carlos Cardenas, Christine Chung, Raphael Douglas, Monique Du Toit, David Jaffray, Anuja Jhingran, Michael Mejia, Raymond Mumme, Sikudhani Muya, Komeela Naidoo, Jerry Ndumbalo, Kelly Nealon, Tucker Netherton, Callistus Nguyen, Niki Olanrewaju, Jeannette Parkes, Willie Shaw, Christoph Trauernicht, Melody Xu, Jinzhong Yang, Lifei Zhang, Hannah Simonds, Beth M Beadle

Faculty, Staff and Student Publications

PURPOSE: Automation, including the use of artificial intelligence, has been identified as a possible opportunity to help reduce the gap in access and quality for radiotherapy and other aspects of cancer care. The Radiation Planning Assistant (RPA) project was conceived in 2015 (and funded in 2016) to use automated contouring and treatment planning algorithms to support the efforts of oncologists in low- and middle-income countries, allowing them to scale their efforts and treat more patients safely and efficiently (to increase access).

DESIGN: In this review, we discuss the development of the RPA, with a particular focus on clinical acceptability and …

Three-Dimensional Microct Imaging Of Mouse Heart Development From Early Post-Implantation To Late Fetal Stages, Nanbing Li-Villarreal, Tara L Rasmussen, Audrey E Christiansen, Mary E Dickinson, Chih-Wei Hsu

Faculty, Staff and Students Publications

Comprehensive detailed characterization of new mouse models can be challenging due to the individual focus involved in developing these models. Often models are engineered to test a specific hypothesis in a limited number of tissues, stages, and/or other contexts. Whether or not the model produces the desired phenotypes, phenotyping beyond the desired context can be extremely work intensive and these studies are often not undertaken. However, the general information resulting from broader phenotyping can be invaluable to the wider scientific community. The International Mouse Phenotyping Consortium (IMPC) and its subsidiaries, like the Knockout Mouse Project (KOMP), has made great strides …

Prospective Validation Of Diffusion-Weighted Mri As A Biomarker Of Tumor Response And Oncologic Outcomes In Head And Neck Cancer: Results From An Observational Biomarker Pre-Qualification Study, Abdallah S R Mohamed, Abdelrahman Abusaif, Renjie He, Kareem A Wahid, Vivian Salama, Sara Youssef, Brigid A Mcdonald, Mohamed Naser, Yao Ding, Travis C Salzillo, Moamen A Abobakr, Jihong Wang, Stephen Y Lai, Clifton D Fuller

Faculty, Staff and Student Publications

PURPOSE: To determine DWI parameters associated with tumor response and oncologic outcomes in head and neck (HNC) patients treated with radiotherapy (RT).

METHODS: HNC patients in a prospective study were included. Patients had MRIs pre-, mid-, and post-RT completion. We used T2-weighted sequences for tumor segmentation which were co-registered to respective DWIs for extraction of apparent diffusion coefficient (ADC) measurements. Treatment response was assessed at mid- and post-RT and was defined as: complete response (CR) vs. non-complete response (non-CR). The Mann-Whitney U test was used to compare ADC between CR and non-CR. Recursive partitioning analysis (RPA) was performed to identify …

Clinical Outcomes Of Immunotherapy Continued Beyond Radiographic Disease Progression In Older Adult Patients With Advanced Non-Small Cell Lung Cancer, Eric K Singhi, Frank Mott, Michelle Worst, Cheuk Hong Leung, J Jack Lee, Brett Carter, Carolyn J Presley, John V Heymach, Mehmet Altan

Faculty, Staff and Student Publications

Immunotherapy is an effective and generally well-tolerated treatment strategy for older adult patients (aged ≥70 years) with advanced non-small cell lung cancer (NSCLC). Unfortunately, most patients who receive immunotherapy eventually exhibit disease progression during treatment. The present study reports on a subset of older adult patients with advanced NSCLC who could effectively continue immunotherapy beyond radiographic disease progression due to perceived clinical benefit. Local consolidative radiotherapy may be used in select older adult patients to prolong the duration of immunotherapy they receive, with a particular consideration of their preexisting co-morbidities, performance status and tolerance of potential toxicities associated with combined …

High-Dose Once-Daily Thoracic Radiotherapy In Limited-Stage Small-Cell Lung Cancer: Calgb 30610 (Alliance)/Rtog 0538, Jeffrey Bogart, Xiaofei Wang, Gregory Masters, Junheng Gao, Ritsuko Komaki, Laurie E Gaspar, John Heymach, James Bonner, Charles Kuzma, Saiama Waqar, William Petty, Thomas E Stinchcombe, Jeffrey D Bradley, Everett Vokes

Faculty, Staff and Student Publications

PURPOSE: Although level 1 evidence supports 45-Gy twice-daily radiotherapy as standard for limited-stage small-cell lung cancer, most patients receive higher-dose once-daily regimens in clinical practice. Whether increasing radiotherapy dose improves outcomes remains to be prospectively demonstrated.

METHODS: This phase III trial, CALGB 30610/RTOG 0538 (ClinicalTrials.gov identifier: NCT00632853), was conducted in two stages. In the first stage, patients with limited-stage disease were randomly assigned to receive 45-Gy twice-daily, 70-Gy once-daily, or 61.2-Gy concomitant-boost radiotherapy, starting with either the first or second (of four total) chemotherapy cycles. In the second stage, allocation to the 61.2-Gy arm was discontinued following planned interim toxicity …

Comparison Of Reconstructed Prompt Gamma Emissions Using Maximum Likelihood Estimation And Origin Ensemble Algorithms For A Compton Camera System Tailored To Proton Range Monitoring, Ingrid Valencia Lozano, George Dedes, Steve Peterson, Dennis Mackin, Andreas Zoglauer, Sam Beddar, Stephen Avery, Jerimy Polf, Katia Parodi

Faculty, Staff and Student Publications

Compton-based prompt gamma (PG) imaging is being investigated by several groups as a potential solution for in vivo range monitoring in proton therapy. The performance of this technique depends on the detector system as well as the ability of the reconstruction method to obtain good spatial resolution to establish a quantitative correlation between the PG emission and the proton beam range in the patient. To evaluate the feasibility of PG imaging for range monitoring, we quantitatively evaluated the emission distributions reconstructed by a Maximum Likelihood Expectation Maximization (MLEM) and a Stochastic Origin Ensemble (SOE) algorithm. To this end, we exploit …

Characterizing The Interplay Of Treatment Parameters And Complexity And Their Impact On Performance On An Iroc Imrt Phantom Using Machine Learning, Hunter Mehrens, Andrea Molineu, Nadia Hernandez, Laurence Court, Rebecca Howell, David Jaffray, Christine B Peterson, Julianne Pollard-Larkin, Stephen F Kry

Faculty, Staff and Student Publications

AIM OF THE STUDY: To elucidate the important factors and their interplay that drive performance on IMRT phantoms from the Imaging and Radiation Oncology Core (IROC).

METHODS: IROC's IMRT head and neck phantom contains two targets and an organ at risk. Point and 2D dose are measured by TLDs and film, respectively. 1,542 irradiations between 2012-2020 were retrospectively analyzed based on output parameters, complexity metrics, and treatment parameters. Univariate analysis compared parameters based on pass/fail, and random forest modeling was used to predict output parameters and determine the underlying importance of the variables.

RESULTS: The average phantom pass rate was …

Applicability And Usage Of Dose Mapping/Accumulation In Radiotherapy, Martina Murr, Kristy K Brock, Marco Fusella, Nicholas Hardcastle, Mohammad Hussein, Michael G Jameson, Isak Wahlstedt, Johnson Yuen, Jamie R Mcclelland, Eliana Vasquez Osorio

Faculty, Staff and Student Publications

Dose mapping/accumulation (DMA) is a topic in radiotherapy (RT) for years, but has not yet found its widespread way into clinical RT routine. During the ESTRO Physics workshop 2021 on "commissioning and quality assurance of deformable image registration (DIR) for current and future RT applications", we built a working group on DMA from which we present the results of our discussions in this article. Our aim in this manuscript is to shed light on the current situation of DMA in RT and to highlight the issues that hinder consciously integrating it into clinical RT routine. As a first outcome of …

Modelling Radiation Cancer Treatment With A Death-Rate Term In Ordinary And Fractional Differential Equations, Nicole Wilson, Corina S Drapaca, Heiko Enderling, Jimmy J Caudell, Kathleen P Wilkie

Faculty, Staff and Student Publications

Fractional calculus has recently been applied to the mathematical modelling of tumour growth, but its use introduces complexities that may not be warranted. Mathematical modelling with differential equations is a standard approach to study and predict treatment outcomes for population-level and patient-specific responses. Here, we use patient data of radiation-treated tumours to discuss the benefits and limitations of introducing fractional derivatives into three standard models of tumour growth. The fractional derivative introduces a history-dependence into the growth function, which requires a continuous death-rate term for radiation treatment. This newly proposed radiation-induced death-rate term improves computational efficiency in both ordinary and …

Pocketnet: A Smaller Neural Network For Medical Image Analysis, Adrian Celaya, Jonas A Actor, Rajarajesawari Muthusivarajan, Evan Gates, Caroline Chung, Dawid Schellingerhout, Beatrice Riviere, David Fuentes

Faculty, Staff and Student Publications

Medical imaging deep learning models are often large and complex, requiring specialized hardware to train and evaluate these models. To address such issues, we propose the PocketNet paradigm to reduce the size of deep learning models by throttling the growth of the number of channels in convolutional neural networks. We demonstrate that, for a range of segmentation and classification tasks, PocketNet architectures produce results comparable to that of conventional neural networks while reducing the number of parameters by multiple orders of magnitude, using up to 90% less GPU memory, and speeding up training times by up to 40%, thereby allowing …

An Untrained Deep Learning Method For Reconstructing Dynamic Mr Images From Accelerated Model-Based Data, Kalina P Slavkova, Julie C Dicarlo, Viraj Wadhwa, Sidharth Kumar, Chengyue Wu, John Virostko, Thomas E Yankeelov, Jonathan I Tamir

Faculty, Staff and Student Publications

PURPOSE: To implement physics-based regularization as a stopping condition in tuning an untrained deep neural network for reconstructing MR images from accelerated data.

METHODS: The ConvDecoder (CD) neural network was trained with a physics-based regularization term incorporating the spoiled gradient echo equation that describes variable-flip angle data. Fully-sampled variable-flip angle k-space data were retrospectively accelerated by factors of R = {8, 12, 18, 36} and reconstructed with CD, CD with the proposed regularization (CD + r), locally low-rank (LR) reconstruction, and compressed sensing with L1-wavelet regularization (L1). Final images from CD + r training were evaluated at the "argmin" of …

Safety Of Nivolumab Added To Chemoradiation Therapy Platforms For Intermediate And High-Risk Locoregionally Advanced Head And Neck Squamous Cell Carcinoma: Rtog Foundation 3504, Maura L Gillison, Robert L Ferris, Jonathan Harris, A Dimitrios Colevas, Loren K Mell, Christina Kong, Richard C Jordan, Kevin L Moore, Minh-Tam Truong, Claudia Kirsch, Arnab Chakravarti, Dukagjin M Blakaj, David A Clump, James P Ohr, John F Deeken, Michael F Gensheimer, Nabil F Saba, Jennifer A Dorth, David I Rosenthal, Rom S Leidner, Randall J Kimple, Mitchell Machtay, Walter J Curran, Pedro Torres-Saavedra, Quynh Thu Le

Faculty, Staff and Student Publications

PURPOSE: Programmed death-1 immune checkpoint blockade improves survival of patients with recurrent/metastatic head and neck squamous cell carcinoma (HNSCC), but the benefits of addition to (chemo)radiation for newly diagnosed patients with HNSCC remain unknown.

METHODS AND MATERIALS: We evaluated the safety of nivolumab concomitant with 70 Gy intensity modulated radiation therapy and weekly cisplatin (arm 1), every 3-week cisplatin (arm 2), cetuximab (arm 3), or alone for platinum-ineligible patients (arm 4) in newly diagnosed intermediate- or high-risk locoregionally advanced HNSCC. Patients received nivolumab from 2 weeks prior to radiation therapy until 3 months post-radiation therapy. The primary endpoint was dose-limiting …

Vidutolimod In Combination With Atezolizumab With And Without Radiation Therapy In Patients With Programmed Cell Death Protein 1 Or Programmed Death-Ligand 1 Blockade-Resistant Advanced Nsclc, Marcelo V Negrao, Vassiliki A Papadimitrakopoulou, Andrew C Price, Alda L Tam, Muhammad Furqan, Sandeep T Laroia, Erminia Massarelli, Jose Pacheco, John V Heymach, Anne S Tsao, Gary V Walker, Lalit Vora, David Mauro, Heather Kelley, James E Wooldridge, Arthur M Krieg, Jiaxin Niu

Faculty, Staff and Student Publications

INTRODUCTION: Vidutolimod, a CpG-A TLR9 agonist, was investigated in a phase 1b study (CMP-001-003; ClinicalTrials.gov, NCT03438318) in combination with atezolizumab with and without radiation therapy (RT) in patients with advanced NSCLC.

METHODS: Patients with progressive disease after anti-programmed cell death protein 1 or programmed death-ligand 1 therapy received either vidutolimod and atezolizumab (part A) or vidutolimod, atezolizumab, and RT (part B). The primary objective was to evaluate the safety of vidutolimod and atezolizumab with and without RT. Key secondary end point was best objective response rate per Response Evaluation Criteria in Solid Tumors, version 1.1.

RESULTS: Between March 28, 2018, …