Radiation Medicine Commons^™

Merging Orthovoltage X-Ray Minibeams Spare The Proximal Tissues While Producing A Solid Beam At The Target, F. A. Dilmanian, S. Krishnan, W. E. Mclaughlin, B. Lukaniec, J. T. Baker, S. Ailawadi, K. N. Hirsch, R. F. Cattell, R. Roy, J. G. Eley, +14 Additional Authors

Journal Articles

© 2019, The Author(s). Conventional radiation therapy of brain tumors often produces cognitive deficits, particularly in children. We investigated the potential efficacy of merging Orthovoltage X-ray Minibeams (OXM). It segments the beam into an array of parallel, thin (~0.3 mm), planar beams, called minibeams, which are known from synchrotron x-ray experiments to spare tissues. Furthermore, the slight divergence of the OXM array make the individual minibeams gradually broaden, thus merging with their neighbors at a given tissue depth to produce a solid beam. In this way the proximal tissues, including the cerebral cortex, can be spared. Here we present experimental …

Evidence For The Role Of Mindfulness In Cancer: Benefits And Techniques., R. Mehta, K. Sharma, L. Potters, A. G. Wernicke, B. Parashar

Journal Articles

Mindfulness is being used increasingly in various aspects of cancer management. Benefits of mindfulness practices are being observed to manage the adverse effects of treatment, symptoms from cancer progression, and the cost-effectiveness compared to conventional contemporary management strategies. In this review article, we present clinical trial data showing the benefits of mindfulness in various aspects of cancer management as well as techniques that have been commonly used in this practice.

Local Radiation Therapy For Palliation In Patients With Multiple Myeloma Of The Spine, D. Mark, P. Gilbo, R. Meshrekey, M. Ghaly

Journal Articles

No abstract provided.

A Model-Based Method For Assessment Of Salivary Gland And Planning Target Volume Dosimetry In Volumetric-Modulated Arc Therapy Planning On Head-And-Neck Cancer., H. Zhang, Y. Cao, J. Antone, A. C. Riegel, M. Ghaly, L. Potters, A. Jamshidi

Journal Articles

This study examined the relationship of achievable mean dose and percent volumetric overlap of salivary gland with the planning target volume (PTV) in volumetric-modulated arc therapy (VMAT) plan in radiotherapy for a patient with head-and-neck cancer. The aim was to develop a model to predict the viability of planning objectives for both PTV coverage and organs-at-risk (OAR) sparing based on overlap volumes between PTVs and OARs, before the planning process. Forty patients with head-and-neck cancer were selected for this retrospective plan analysis. The patients were treated using 6 MV photons with 2-arc VMAT plan in prescriptions with simultaneous integrated boost …

Dna Damage And Cytokine Production In Non-Target Irradiated Lymphocytes, Jane Bryant, Laura Shields, Christopher Hynes, Orla L. Howe, Brendan Mcclean, Fiona Lyng

Articles

In advanced radiotherapy, treatment of the tumor with high-intensity modulated fields is balanced with normal tissue sparing. However, the non-target dose delivered to surrounding healthy tissue within the irradiated volume is a potential cause for concern. Whether the effects observed are caused after exposure to out-of-field radiation or bystander effects through neighboring irradiated cells is not fully understood. The goal of this study was to determine the effect of exposure to out-of-field radiation in lymphocyte cell lines and primary blood cells. The role of cellular radiosensitivity in altering bystander responses in out-of-field exposed cells was also investigated. Target cells were …

Dosimetric Performance And Planning/Delivery Efficiency Of A Dual-Layer Stacked And Staggered Mlc On Treating Multiple Small Targets: A Planning Study Based On Single-Isocenter Multi-Target Stereotactic Radiosurgery (Srs) To Brain Metastases., Taoran Li, Peyton Irmen, Haisong Lui, Wenyin Shi, Michelle Alonso-Basanta, Wei Zou, Boon-Keng Kevin Teo, James M. Metz, Lei Dong

Department of Radiation Oncology Faculty Papers

Purpose: To evaluate the dosimetric performance and planning/delivery efficiency of a dual-layer MLC system for treating multiple brain metastases with a single isocenter.

Materials and Methods: 10 patients each with 6-10 targets with volumes from 0.11 to 8.57 cc, and prescription doses from 15 to 24 Gy, were retrospectively studied. Halcyon has only coplanar delivery mode. Halcyon V1 MLC modulates only with the lower layer at 1 cm resolution, whereas V2 MLC modulates with both layers at an effective resolution of 0.5 cm. For each patient five plans were compared varying MLC and beam arrangements: the clinical plan using multi-aperture …

A Custom Radiopaque Thermoresponsive Chemotherapy-Loaded Hydrogel For Intratumoural Injection: An In Vitro And Ex Vivo Assessment Of Imaging Characteristics And Material Properties, Seóna M. Rossi, Timothy E. Murray, John Cassidy, Michael J. Lee, Helena M. Kelly

Articles

Purpose Thermoresponsive hydrogels are gels which have different properties at varying temperatures. The objective of this study was to assess the material characteristics, imaging properties and chemotherapeutic drug release profile of a novel radiopaque thermoresponsive hydrogel in vitro, which is liquid at room temperature but solidifies at body temperature, to determine potential suitability for intratumoural delivery. Materials and Methods An iodinated radiopaque thermoresponsive hydrogel was formulated using iodixanol at a range of concentrations and assessed for sol–gel transition, radiopacity and imaging using CT and US. A lead formulation containing iodixanol at a concentration of 9.22% weight by weight (w/w, g …

Recent Advances In The Vibrational Spectroscopic Diagnosis Of Non-Small Cell Lung Cancer, Declan O'Dea, Fiona Lyng, Siobhan Nicholson, Finbar O'Connell, Aoife Maguire, Alison Malkin

Articles

Lung cancer is the leading cause of cancer deaths worldwide accounting for 1.69 million deaths in 2015. Studies have indicated a 5 year survival rate of 8%–15% in western countries, although a survival rate as low as 1% has been demonstrated for late stage diagnosis. With the advent of targeted therapies, it is imperative to accurately differentiate non-small cell lung cancer (NSCLC) subtypes in order to ensure efficacy of treatment for patients. Immunohistochemistry and molecular techniques for the diagnosis of NSCLC are increasingly part of the diagnostic algorithm and clinical work-up of lung cancer patients, however due to the limitation …

Measurement Of The Whole Body, Eye Lens And Extremity Occupational Exposures In Nuclear Medicine Staff At King Chulalongkorn Memorial Hospital, Siriwan Sisai

Chulalongkorn University Theses and Dissertations (Chula ETD)

Due to the epidemiology evidence of cataract and eye lens opacity, ICRP Publication 118 in 2012, recommended the new eye lens dose limit of occupational exposure at 20 mSv/year, averaged over 5-year periods, no single year exceeding 50 mSv. For the public eye lens dose limit is 15 mSv/year. After ICRP changed the eye lens dose limit, many reports on eye lens dose measurement using thermoluminescent dosimeter (TLD) from interventional radiologists and interventional cardiologists were published. Few reports on eye lens dose measurement in nuclear medicine (NM) personnel were found. The primary objective of this study is to measure whole …

A Feasibility Study Of Diffusion Weighted Imaging And Parametric Response Map Analysis For Treatment Response Prediction In Nasopharyngeal Cancer, Titiya Jirawatwanith

Chulalongkorn University Theses and Dissertations (Chula ETD)

Diffusion-weighted imaging (DWI) is an MRI technique which provides functional information of tissue by detecting microscopic motion of water molecules. The change of apparent diffusion coefficient (ADC) derived from DWI was used as an imaging biomarker for treatment response prediction in cancers. However, it was based on whole-tumor analysis which did not reflect heterogeneity within the tumor. To overcome this limitation, a new method called parametric response map (PRM) analysis was proposed to evaluate response by quantifying voxel-wise changes in ADC. Here we investigated the use of PRM analysis on ADC from DWI as an imaging biomarker for treatment response …

Dosimetric Comparison Between Single And Double Isocenters Volumetric Arc Therapy For Stereotactic Radiotherapy With Multiple Targets, Wai Lwin Lwin Kyaw

Chulalongkorn University Theses and Dissertations (Chula ETD)

The purpose of this study was to evaluate the dosimetric effects between single isocenter (SI) and double isocenters (DI) VMAT SRT of multiple brain metastases. There are two parts of study, which were experimental for energy selection, technique comparison and clinical part to use appropriate technique. As the first part, three lesions with 3 cm distance apart and 1 cm size for all lesions were created as standard plan by varying energy. Twelve VMAT SRT plans by varying energy with 6 MV, 10 MV, 6 FFF and 10 FFF were planned on simulated three lesions of CT image. 18 VMAT …

Effect Of Neoadjuvant Chemoradiation On Preoperative Pulmonary Physiology, Postoperative Respiratory Complications And Quality Of Life In Patients With Oesophageal Cancer, J. A. Elliott, L. O'Byrne, G. Foley, C. F. Murphy, Suzanne Doyle, S. King, E. M. Guinan, N. Ravi, V. Reynolds

Articles

Background: It remains controversial whether neoadjuvant chemoradiation (nCRT) for oesophageal cancer influences operative morbidity, in particular pulmonary, and quality of life. This study combined clinical outcome data with systematic evaluation of pulmonary physiology to determine the impact of nCRT on pulmonary physiology and clinical outcomes in locally advanced oesophageal cancer.

Methods: Consecutive patients treated between 2010 and 2016 were included. Three-dimensional conformal radiation was standard, with a lung dose–volume histogram of V20 less than 25 per cent, and total radiation between 40 and 41⋅4Gy. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and diffusion capacity …

An Ensemble Of Flexible Conformations Underlies Mechanotransduction By The Cadherin–Catenin Adhesion Complex, Martin Bush, Bashir M. Alhanshali, Shuo Qian, Christopher B. Stanley, William T. Heller, Tsutomu Matsui, Thomas M. Weiss, Iain D. Nicholl, Thomas Walz, David J. E. Callaway, Zimei Bu

Publications and Research

The cadherin–catenin adhesion complex is the central component of the cell–cell adhesion adherens junctions that transmit mechanical stress from cell to cell. We have determined the nanoscale structure of the adherens junction complex formed by the α-catenin•β-catenin•epithelial cadherin cytoplasmic domain (ABE) using negative stain electron microscopy, small-angle X-ray scattering, and selective deuteration/small-angle neutron scattering. The ABE complex is highly pliable and displays a wide spectrum of flexible structures that are facilitated by protein-domain motions in α- and β-catenin. Moreover, the 107-residue intrinsically disordered N-terminal segment of β-catenin forms a flexible “tongue” that is inserted into α-catenin and participates in the …

Spaceoar To Improve Dosimetric Outcomes For Monotherapy High-Dose-Rate Prostate Implantation In A Patient With Ulcerative Colitis., Michael Trager, Benjamin Greenberger, Amy S. Harrison, James Keller, Robert B. Den

Department of Radiation Oncology Faculty Papers

High-dose-rate (HDR) brachytherapy is an attractive option for patients receiving definitive radiation therapy for prostate cancer with decreased overall dose to the pelvis. However, ulcerative colitis increases rectal toxicity risk and may be a contraindication. A synthetic hydrogel, SpaceOAR (Augmentix Inc., Waltham, MA, USA), can facilitate the use of HDR brachytherapy for patients where rectal toxicity is a limiting factor. SpaceOAR gel (13.19 cc) was utilized in a monotherapy HDR prostate treatment with Ir-192 under transrectal ultrasound guidance, with the intention of decreasing rectal dose. SpaceOAR gel was inserted transperineally into the patient 18 days prior to the procedure. The …

Challenges Faced By Pakistani Healthcare System: Clinician's Perspective, Faran Khalid, Ahmed Nadeem Abbasi

Department of Radiation Oncology

Abstract are not provided by the author/publisher

Clinical Audit To Assess Delays In Chemotherapy Administration At Daycare Oncology Center At A Tertiary Care Hospital In Karachi, Pakistan, Arifa Arifa Aziz, Zarka Samoon, Afsheen Feroz, Nadia Ayoub, Safia Awan, Madhia Beg

Department of Radiation Oncology

Aim: There were delays reported by patients in chemotherapy administration in daycare oncology. Therefore, we decided to audit all processes which are involved in chemotherapy administration. The objective was to improve our service by decreasing the time between admission and initiation of chemotherapy and identify the reasons for delays. Materials and Methods: The audit was conducted in three parts. In Review I, audit tool was developed and information documented of 109 patients receiving chemotherapy at daycare center from April 14 to May 13, 2015. Five processes were assessed out of which delay in initial assessment by the nurse was the …

Development And Validation Of A Prostate Cancer Genomic Signature That Predicts Early Adt Treatment Response Following Radical Prostatectomy., R. Jeffrey Karnes, Vidit Sharma, Voleak Choeurng, Hussam Al-Deen Ashab, Nicholas Erho, Mohammed Alshalalfa, Bruce Trock, Ashley Ross, Kasra Yousefi, Harrison Tsai, Shuang G. Zhao, Jeffrey J. Tosoian, Zaid Haddad, Mandeep Takhar, S. Laura Chang, Daniel E. Spratt, Firas Abdollah, Robert B. Jenkins, Eric A. Klein, Paul L. Nguyen, Adam P. Dicker, Robert B. Den, Elai Davicioni, Felix Y. Feng, Tamara L. Lotan, Edward M. Schaeffer

Department of Radiation Oncology Faculty Papers

Purpose: Currently, no genomic signature exists to distinguish men most likely to progress on adjuvant androgen deprivation therapy (ADT) after radical prostatectomy for high-risk prostate cancer. Here we develop and validate a gene expression signature to predict response to postoperative ADT.

Experimental Design: A training set consisting of 284 radical prostatectomy patients was established after 1:1 propensity score matching metastasis between adjuvant-ADT (a-ADT)-treated and no ADT–treated groups. An ADT Response Signature (ADT-RS) was identified from neuroendocrine and AR signaling–related genes. Two independent cohorts were used to form three separate data sets for validation (set I, n = 232; set II, …

Prognostic Factors For Elderly Patients Treated With Stereotactic Body Radiation Therapy For Pancreatic Adenocarcinoma, Philip A. Sutera, Mark E. Bernard, Hong Wang, Dwight E. Heron

Radiation Medicine Faculty Publications

Introduction: Pancreatic ductal adenocarcinoma (PDAC) commonly presents later in life with a median age at diagnosis of 70 years. Unfortunately, elderly patients are significantly underrepresented in clinical trials. Stereotactic body radiation therapy (SBRT) is a promising treatment modality in this population as it has demonstrated excellent local control with minimal toxicity. We aimed to determine prognostic factors associated with outcomes in elderly patients treated with SBRT.

Materials and Methods: Elderly patients older than 70 treated with SBRT for PDAC at our institution, from 2004 to 2014 were included. Our primary endpoints included overall survival (OS) and local-progression-free survival (LPFS). Secondary …

Impact Of The Spop Mutant Subtype On The Interpretation Of Clinical Parameters In Prostate Cancer., Deli Liu, Mandeep Takhar, Mohammed Alshalalfa, Nicholas Erho, Jonathan Shoag, Robert B. Jenkins, R. Jeffrey Karnes, Ashley E. Ross, Edward M. Schaeffer, Mark A. Rubin, Bruce Trock, Eric A. Klein, Robert B. Den, Scott A. Tomlins, Daniel E. Spratt, Elai Davicioni, Andrea Sboner, Christopher E. Barbieri

Department of Radiation Oncology Faculty Papers

Purpose: Molecular characterization of prostate cancer, including The Cancer Genome Atlas, has revealed distinct subtypes with underlying genomic alterations. One of these core subtypes, SPOP (speckle-type POZ protein) mutant prostate cancer, has previously only been identifiable via DNA sequencing, which has made the impact on prognosis and routinely used risk stratification parameters unclear.

Methods: We have developed a novel gene expression signature, classifier (Subclass Predictor Based on Transcriptional Data), and decision tree to predict the SPOP mutant subclass from RNA gene expression data and classify common prostate cancer molecular subtypes. We then validated and further interrogated the association of prostate …

Open Book Testing In Health Science Education: Student Perceptions And Outcomes In Ultrasound Physics, Kim Michael, Tanya M. Custer

Posters and Presentations: Medical Imaging & Therapeutic Sciences

Objectives: The purpose of this study was to investigate the use of open book exams (OBE) in the education of imaging students and to assess the beliefs and perceptions of the students in regard to the use of open book testing.

Subjects & Methods: Study participants included twenty-seven sonography students enrolled in an academic health sciences center. OBE was implemented in two ultrasound physics courses. Data was collected through focus groups & exam outcomes. Creswell’s procedure for data analysis & representation was followed.

Results: Overall outcomes showed no statistically significant difference between exam grades for the different cohorts with the …