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Simulation study of proton arc therapy with the compact single-room MEVION-S250 proton therapy system
- Sven Ferguson, Salahuddin Ahmad, Imad Ali
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- Journal:
- Journal of Radiotherapy in Practice / Volume 19 / Issue 4 / December 2020
- Published online by Cambridge University Press:
- 27 January 2020, pp. 347-354
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Aim:
The purpose of this study is to investigate the feasibility of proton arc therapy (PAT) using the double-scattering MEVION-S250 proton system. The treatment planning and dose delivery parameters from PAT were compared with conventional treatment planning techniques.
Materials and methods:PAT was simulated with multiple conformal and fixed-aperture beams (5–15) using the MEVION-S250-double-scattering proton system. Conformal apertures were simulated with the Eclipse-treatment-planning system: (a) using a static single aperture that provides the best average conformal circular or rectangular apertures to cover the tumour from different angular views (SPAT), and (b) dynamic conformal apertures of the tumour shape at each irradiation angle that can be obtained from a multi-leaf-collimator system (DPAT).
Results:The DPAT and SPAT plans provided superior dose coverage and sparing of normal tissues in comparison with conventional plans (CPT). The entrance normal tissue and skin doses (<40%) were lowered significantly by delivering dose from different directions over a wider angular view compared to conventional plans that have large entrance dose from only two fields. While the mean and minimum doses from PAT and CPT were comparable, the maximum doses from arc plans were lower than the maximum doses in conventional plans. The SPAT and DPAT plans had comparable dose parameters for regularly shaped targets. The heterogeneity index (HI) was superior in PAT plans which improved with increasing number of beams in arc plans for the different treatment sites. The conformality index (CI) depends on the treatment site and complexity of the shape of the planning target volume where for brain, pancreatic and lung tumours, PAT plans conformality was comparable and sometimes superior to CPT; and HI and CI were generally better in DPAT compared to SPAT.
Conclusions:PAT plans have superior dose coverage and sparing of normal tissues compared to CPT plans using the MEVION double-scattering system as shown in this simulation study. Ideally, conformal proton arcs require beam shaping and dose delivery with the gantry moving; however, the MEVION double-scattering system lacks a multi-leaf collimator system and cannot deliver dose during gantry rotation. The single aperture conformal proton therapy technique is more time and cost effective compared with conventional techniques that are used currently with the MEVION proton therapy system because of the elimination of the need for patient-specific compensators. In present study, PAT was simulated with the MEVION double-scattering proton therapy system; however, it can be performed also with other proton therapy systems.
Contributors
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- By Elias Aboujaoude, Tina S. Alster, April Lane Benson, Wolfgang Berner, Donald W. Black, Dana Bodnik, Peer Briken, Raul Caetano, Celal Çalıkuşu, Joan C. Chrisler, Emil F. Coccaro, Pinhas N. Dannon, Helga Dittmar, Sheila Ferguson, Candice Germain, Jon E. Grant, John H. Greist, Andreas Hill, Lorrin M. Koran, Michel Lejoyeux, Laura M. Letson, Timothy Liu, Eileen M. Luna-Firebaugh, Michael S. McCloskey, Duane C. McKay, Christy M. McKinney, Amy McMichael, Drew Miller, Brad Novak, Brian L. Odlaug, Christina S. Pearson, Guy Porter, Marc N. Potenza, Paul Schwartzman, William M. Spice, Vladan Starcevic, Özlem Tecer, Benjamin T. P. Tucker, Michael R. Walther, Rungsima Wanitphakdeedecha, Sven E. Widmalm, Timothy Ivor Williams, Reeta Wolfsohn, Douglas W. Woods
- Edited by Elias Aboujaoude, Stanford University School of Medicine, California, Lorrin M. Koran, Stanford University School of Medicine, California
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- Book:
- Impulse Control Disorders
- Published online:
- 06 July 2010
- Print publication:
- 08 February 2010, pp ix-xii
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The case for strategic international alliances to harness nutritional genomics for public and personal health†
- Jim Kaput, Jose M. Ordovas, Lynnette Ferguson, Ben van Ommen, Raymond L. Rodriguez, Lindsay Allen, Bruce N. Ames, Kevin Dawson, Bruce German, Ronald Krauss, Wasyl Malyj, Michael C. Archer, Stephen Barnes, Amelia Bartholomew, Ruth Birk, Peter van Bladeren, Kent J. Bradford, Kenneth H. Brown, Rosane Caetano, David Castle, Ruth Chadwick, Stephen Clarke, Karine Clément, Craig A. Cooney, Dolores Corella, Ivana Beatrice Manica da Cruz, Hannelore Daniel, Troy Duster, Sven O. E. Ebbesson, Ruan Elliott, Susan Fairweather-Tait, Jim Felton, Michael Fenech, John W. Finley, Nancy Fogg-Johnson, Rosalynn Gill-Garrison, Michael J. Gibney, Peter J. Gillies, Jan-Ake Gustafsson, John L. Hartman IV, Lin He, Jae-Kwan Hwang, Jean-Philippe Jais, Yangsoo Jang, Hans Joost, Claudine Junien, Mitchell Kanter, Warren A. Kibbe, Berthold Koletzko, Bruce R. Korf, Kenneth Kornman, David W. Krempin, Dominique Langin, Denis R. Lauren, Jong Ho Lee, Gilbert A. Leveille, Su-Ju Lin, John Mathers, Michael Mayne, Warren McNabb, John A. Milner, Peter Morgan, Michael Muller, Yuri Nikolsky, Frans van der Ouderaa, Taesun Park, Norma Pensel, Francisco Perez-Jimenez, Kaisa Poutanen, Matthew Roberts, Wim H.M. Saris, Gertrud Schuster, Andrew N. Shelling, Artemis P. Simopoulos, Sue Southon, E. Shyong Tai, Bradford Towne, Paul Trayhurn, Ricardo Uauy, Willard J. Visek, Craig Warden, Rick Weiss, John Wiencke, Jack Winkler, George L. Wolff, Xi Zhao-Wilson, Jean-Daniel Zucker
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- Journal:
- British Journal of Nutrition / Volume 94 / Issue 5 / November 2005
- Published online by Cambridge University Press:
- 08 March 2007, pp. 623-632
- Print publication:
- November 2005
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Nutrigenomics is the study of how constituents of the diet interact with genes, and their products, to alter phenotype and, conversely, how genes and their products metabolise these constituents into nutrients, antinutrients, and bioactive compounds. Results from molecular and genetic epidemiological studies indicate that dietary unbalance can alter gene–nutrient interactions in ways that increase the risk of developing chronic disease. The interplay of human genetic variation and environmental factors will make identifying causative genes and nutrients a formidable, but not intractable, challenge. We provide specific recommendations for how to best meet this challenge and discuss the need for new methodologies and the use of comprehensive analyses of nutrient–genotype interactions involving large and diverse populations. The objective of the present paper is to stimulate discourse and collaboration among nutrigenomic researchers and stakeholders, a process that will lead to an increase in global health and wellness by reducing health disparities in developed and developing countries.