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  Prostatic Urethral Length on MRI as a Predictor of Late Genitourinary Toxicity After Prostate Cancer Radiation

  Kyu Kim, Joseph Lee, Allison Hazy, Sayf Al-Katib, Hong Ye, Nathan Kolderman, Abhay Dhaliwal, Daniel Krauss, Thomas Quinn, Kimberly Marvin, and Kiran R. Nandalur

  Publication Date: 5-2025

  Radiation therapy (RT) is a widely used treatment for prostate cancer.1 While effective, some patients develop late genitourinary (GU) toxicity, which can impact quality of life.2,4 Identifying pre-treatment factors that predict toxicity risk may help improve clinical decision-making. Recent studies suggest that prostatic urethral length (PUL) seen on MRI is associated with an increased risk of late GU toxicity.3 Understanding this relationship could enhance risk stratification before treatment.

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  Toxicity and Clinical Outcomes Following Brachytherapy Using 3-D Dosimetric Planning in Patients with Cervical Cancer: An Institutional Experience

  Nikita M. Patel, Jacob F. Oyeniyi, and Maha Saada Jawad

  Publication Date: 5-2025

  • Cervical cancer is the most common gynecological cancer worldwide.1

  • The standard of care for locally advanced cervical cancer (LACC) includes primary chemoradiation, brachytherapy, and external-beam radiotherapy.2

  • Brachytherapy (BT) involves the targeted delivery of radiation to the cervix (Fig 1). However, radiation can be toxic to surrounding structures, most commonly affecting the gynecological, genitourinary, and gastrointestinal systems.3

  • Historically, brachytherapy was planned using a 2-D approach, which had limitations in accuracy and increased toxicity to the adjacent bowel and bladder. 3-D planning using CT or MRI has been shown to have improved dose precision and reduced toxicity.4

  • This study aims to evaluate toxicity and clinical outcomes for patients treated at our institution utilizing this method, contributing to existing literature and assessing institutional results.

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  Comparison of two adjuvant high-dose rate vaginal cuff brachytherapy dose fractionation regimens for treatment of early-stage uterine cancer

  Catherine Raciti, Hong Ye, Allison J. Hazy, and Maha Saada Jawad

  Publication Date: 5-2025

  • Endometrial cancer is the most common gynecologic malignancy in the United States, with peak incidence at 63 years of age.¹

  • PORTEC-2 trial established VBT alone as an effective modality for select high-intermediate risk patients.2

  • There was no strict ABS guideline for dose fractionation; our institution adopted a 30Gy in 6 fractions regimen based on radiobiological calculations.3,4

  • COVID-19 pandemic led to a shift towards 22Gy in 4 fractions

  • Objective: Compare oncologic outcomes and toxicity between the 30Gy/6fx and 22Gy/4fx regimens.

  • Hypothesis: Both regimens are well-tolerated and equally effective.

  • Impact: Findings will inform clinical practice and guide future treatment protocols for early-stage endometrial cancer.

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  Clinical Outcomes of Hypofractionated Whole Breast Irradiation In Early Stage, Biologically High-Risk Breast Cancer

  Eva Leung, Benjamin D. Willen, Thomas J. Quinn, Muayad F. Almahari, Peter Y. Chen, Maha Saada Jawad, Gregory S. Gustafson, Michelle Ka Yan Wu, and Joshua T. Dilworth

  Publication Date: 5-2024

  • Whole breast irradiation (WBI) has been used in the treatment of breast cancer patients after partial mastectomy.
  • There has been increasing utilization of hypofractionated whole breast irradiation (HWBI), defined as a larger daily dose and fewer fractions compared to conventionally fractionated whole breast irradiation (CWBI). However, HWBI for patients with early-stage, biologically high-risk breast cancer remains relatively low.
  • We define biologically high-risk breast cancer as either triple negative (estrogen receptor/progesterone receptor/human epidermal growth factor receptor 2 (Her-2) negative), Her-2 amplified, and/or patients with a high-risk multigene assay.
  • The 2018 ASTRO guidelines form the basis for treating breast cancer patients with HWBI. In regards to breast cancer receptor status, there is only a “moderate” quality of evidence leading to a conditional recommendation of HWBI for breast cancer patients with varying hormone receptor and Her-2 status.
  • The underrepresentation of patients with biologically high-risk breast cancer in prior studies comparing HWBI and CWBI also contributed to physician reluctance in offering HWBI to this patient population.
  • • The primary goal of this study is to compare the clinical outcomes of CWBI versus moderate HWBI in patients with early-stage, biologically high-risk breast cancer.

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  Breast Irradiation is Well Tolerated in Carriers of a Pathogenic ATM Variant

  Leah R. Rotenbakh, Andrew H. Zureick, Dana Zakalik, Thomas J. Quinn, Vincent P. Grzywacz, Peter Y. Chen, and Joshua T. Dilworth

  Publication Date: 5-2024

  • The ataxia telangiectasia mutant (ATM) gene is implicated in DNA damage repair.
  • A pathogenic germline variant of the ATM gene is present in approximately 1% of the population.
  • ATM gene variant increases radiation sensitivity and elevates the life-time risk of developing breast cancer by two- to four-fold.
  • Potential for increased radiosensitivity poses concern for the utilization of radiation therapy (RT) for oncologic treatment in patients with the ATM gene variant.
  • Current data regarding RT tolerance are limited and conflicting in this patient population.
  • Current guidelines for hereditary breast cancer management issued jointly by the American Society for Radiation Oncology, American Society of Clinical Oncology, and the Society of Surgical Oncology in 2020 recommend that radiation should not be avoided in patients with the pathogenic ATM variant, but the quality of evidence supporting this recommendation was low with moderate strength at the time.

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  Hypofractionated Regional Nodal Irradiation in Breast Cancer

  Joseph Salib, Allison Hazy, and Joshua T. Dilworth

  Publication Date: 5-2024

  • In women with breast cancer requiring whole breast irradiation therapy (WBI), current guidelines endorse moderately hypofractionated whole breast irradiation (HWBI), which includes a shorter, 3-4-week regimen of radiation with a higher dose per daily fraction in comparison to conventional whole breast irradiation (CWBI), which includes a 5-6.5-week regimen.
  • Patients with certain risk factors may benefit from treatment to the regional lymph nodes (RNI), which include the ipsilateral axillary, internal mammary and supraclavicular chains.
  • Some centers have been slower to adopt short-course treatment when regional lymph nodes also require treatment (H-RNI), despite a reduction in the number of treatments for the patient, less restriction on time for the treating facility and an increase in cost effectiveness for hospital systems. This is in part due to the lack of data surrounding the use of H-RNI.
  • In this study, we report the acute and chronic toxic effects in patients treated with H-RNI.

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  Near-Surface Dose Correlates With Moist Desquamation and Unplanned Reconstructive Surgery in Patients With Implant-Based Reconstruction Receiving Postmastectomy Radiation Therapy

  Patrick Thrasher, Ronald Levitin, Bryan S. Squires, Allison J. Hazy, Michael J. Maywood, Anthony P. Delise, Muayad F. Almahariq, Nayana Dekhne, Lauren Oliver, Peter Y. Chen, Kailee J. Walters, Diane Dudley, and Joshua T. Dilworth

  Publication Date: 5-2024

  Postmastectomy radiation therapy (PMRT) utilized as part of a breast cancer treatment regimen reduces the risk of disease recurrence in appropriately selected patients.1,2,3,4,5 However, PMRT increases risk of radiationrelated toxicities that can interfere with breast reconstruction post-mastectomy.6 Following mastectomy, implant-based reconstruction can increase patient satisfaction and quality of life7,8; complications induced by PMRT such as infection and tissue contracture, though, increase risk for implant loss and may ultimately require further surgeries for the patient.

  PMRT is delivered based on treatment plans that are optimized to provide appropriate radiation dosages to tissues along the chest wall while simultaneously limiting exposure of surrounding sensitive structures. Subcutaneous lymphatic structures and residual glandular tissue are of major importance as they may harbor microscopic disease that can lead to recurrence.9 The skin and immediate surrounding tissue, therefore, is often exposed to higher doses of radiation to ensure appropriate therapeutic coverage of these structures. How this increased dose delivery may affect a patient’s risk for radiation-related toxicities, however, is currently not well characterized. We hypothesize that near-surface dose to the reconstructed chest wall predicts for an increased risk of significant breast pain as well as the development of acute skin toxicities such as moist desquamation. Identifying dosimetric correlates for these acute toxicities may allow for optimization of radiation treatment planning aimed at reducing the incidence of acute toxicities and further associated complications.

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  Tumor Locations Impact on Cardiac Toxicity in Women that Received Partial Breast Irradiation

  Sara Diltz, Muayad Almahariq, and Joshua Dilworth

  Publication Date: 5-2023

  Accelerated partial breast irradiation (APBI) is an appropriate modality for select women with low-risk breast cancer. While APBI delivers radiation dose to a smaller volume of breast tissue compared to whole breast irradiation, dose to the heart and coronary vessels may be relatively high, depending on the proximity of the treatment device to these structures. The primary goal of this study is to determine if the risk of adverse cardiac events depends on tumor location in women receiving APBI.

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  High Dose Rate Brachytherapy monotherapy versus External Beam Radiotherapy with HDR Brachytherapy Boost for Unfavorable Intermediate Prostate Cancer Patients

  Doyle Lang, Benjamin Willen, Daniel J. Krauss, and Sirisha R. Nandalur

  Publication Date: 5-2023

  Prostate cancer is the most common male malignancy by incidence in the world. Treatment differs by the patient’s risk stratification. For the treatment of unfavorable intermediate-risk prostate cancer, external beam radiotherapy with high-dose-rate brachytherapy boost was the accepted treatment but high-dose-rate brachytherapy as monotherapy has been proposed as a potentially viable treatment option. External beam radiotherapy treatment involves shooting high-energy photons or particle radiation through normal healthy tissue to hit the tumor directly. High-dose-rate brachytherapy involves inserting radioactive seeds into the tumor. Studies are needed to compare toxicity profiles and relative outcomes between the two treatment options.

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  Outcomes of Locally Advanced Lung Cancer Patients Treated with 60 Gy vs. 70 Gy

  Batoul Nasser, Muyad Almahariq, and Inga Grills

  Publication Date: 5-2023

  The standard form of treatment for locally advanced lung cancer is to prescribe the conventional dose of 60 Gy radiation therapy (RT) concurrently with chemotherapy. However, five-year overall survival is still less than 20%. These outcomes remain poor due to both distant and local regional recurrence. The literature suggests that local regional control and overall survival is strongly associated with doses of radiotherapy that are higher than 60 Gy. However, when escalating radiation dose was prescribed exceeding 70 Gy, the overall survival rates plateaued. The primary goal of this study is to determine if there is a marked difference in clinical outcomes (i.e., mortality, disease progression, local recurrence) when administering varying RT doses – standard 60 Gy vs. simulated integrated boost (SIB) to 70 Gy – in concordance with chemotherapy, to patients with locally advanced lung cancer. A secondary goal is to determine if our findings support of contradict the results of previous studies that examined escalating doses of radiotherapy.

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  Dose to the Left Anterior Descending Artery Correlates With Cardiac Events After Irradiation for Breast Cancer

  Brittany Silverman, Andrew Zureick, Vincent Grzywacz, Muayad Almahariq, Aleksander Vayntraub, and Joshua Dilworth

  Publication Date: 5-2023

  Although global heart dose has been associated with late cardiac toxic effects in patients who received radiation therapy for breast cancer, data detailing the clinical significance of cardiac substructure dosimetry are limited. We investigated whether dose to the left anterior descending artery (LAD) correlates with adverse cardiac events.

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  Influence of Pretreatment Magnetic Resonance Imaging on Local Therapy Decisions for Intermediate-Risk Prostate Cancer Patients

  Christian Skowronski, Andrew Shanholtzer, Brent Yelton, Muayad Almahariq, and Daniel Krauss

  Publication Date: 5-2023

  Prostate cancer has the third highest incidence rate and is the second leading cause of cancer death for men in the United States. Magnetic resonance imaging (MRI) provides superior soft tissue delineation serving as a valuable tool for both diagnosis and treatment planning. With minimal data regarding utility on diagnosis and treatment planning for intermediate-risk prostate cancer, the National Comprehensive Cancer Network’s guidelines indicate MRI as optional in intermediate-risk prostate cancer evaluation. This project aims to elucidate whether MRI affects radiation treatment decisions for intermediate-risk prostate cancer.

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  The Prognostic Significance of Glucose-6-Phosphate Dehydrogenase as a Biomarker in Head and Neck Squamous Cell Carcinomas Treated with Conventional Chemoradiation

  Kenneth H. Barker, Barbara L. Pruetz, Jessica D. Arden, Thomas J. Quinn, and George D. Wilson

  Publication Date: 5-2-2022

  INTRODUCTION
  The prognosis of patients with head and neck squamous cell carcinoma (HNSCC) treated with chemoradiation can be predicted using p16 as a surrogate biomarker of Human Papilloma Virus (HPV) status, but a subset of patients continues to do poorly despite a positive or negative p16 status. This project attempted to identify another biomarker, glucose-6-phosphate dehydrogenase (G6PD) as a marker for prognosis in HNSCC patients. Radiation induces oxidative damage to destroy tumor cells, and G6PD is a key enzyme involved in protecting cells from oxidative damage. The goal of this project was to identify a prognostic biomarker that would aid in recognizing patients who would not respond well to chemoradiation and potentially respond better to other therapeutic measures.

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  Functional Lung Segmentation from Computed Tomography Images using Deep Learning

  Duyen M. Quach, Evan Porter, and Thomas M. Guerrero

  Publication Date: 5-2-2022

  INTRODUCTION
  Functional avoidance treatment planning allows radiation oncologists to intentionally minimize radiation dose to higher-functioning lung areas while favoring radiation dose towards lower-functioning regions. This treatment planning method has been shown to reduce pulmonary toxicity for patients receiving radiation therapy. Functional lung information, traditionally ventilation or perfusion SPECT scans, is required to plan for functional avoidance.

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  Evaluating the Impact of Software Distortion Correction on Target Doses in Cranial Stereotactic Radiosurgery

  Sharjil Shamim and Zachary Seymour

  Publication Date: 5-2-2022

  INTRODUCTION
  Brainlab’s Elements suite proposed a novel MR distortion correction method based on CT imaging. This involves registration of sub-volumes from MR imaging to generate single continuous deformation field maps, creating a corrected MR image set. No literature currently exists studying the impact of software correction on target dose for cranial stereotactic radiosurgery. In this study, we aim to evaluate the impact of Brainlab distortion correction on radiation target dose compared to original treatment plans without distortion correction.

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  Fluoroscopic Demonstration of Thoracic Tumor Immobilization with High Frequency Percussive Ventilation

  Cristian Solano, Ina M. Sala, Beverly Maurer, Ronald Levitin, and Thomas M. Guerrero

  Publication Date: 5-2-2022

  INTRODUCTION
  High frequency percussive ventilation (HFPV) is a novel immobilization technique that utilizes high frequency low tidal volume ventilation to produce endotracheal percussion. In a previous departmental study of chest wall motion immobilization, it was found that volunteers were able to tolerate HFPV for varying lengths of time – from a few to tens of minutes. By investigating a novel process to immobilize the chest wall, and thus thoracic tumors, it can allow for more localized radiation delivery and reduction of healthy tissue irradiation.

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  Development of A Deep Neural Network for Synthesis of Non-Contrast Cranial T1-Weighted Magnetic Resonance Imaging

  Agueda M. Taylor, Evan Porter, and Thomas Guerrero

  Publication Date: 5-2-2022

  INTRODUCTION
  Although 122 out of 1000 people in the US have MRI’s done each year, there are over 4 million with contraindications that subsequently forgo the diagnostic benefits. Studies in recent years have implemented artificial intelligence (AI) algorithms such as deep neural networks (DNN) for production of synthetic medical imaging. The goals of this project are to develop a DNN, specifically a Generative Adversarial Network (GAN) that will predict synthetic Cranial T1 Weighted MRI from non-contrast CT, and to evaluate the model quality.