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Title: Sci—Fri PM: Topics — 07: Monte Carlo Simulation of Primary Dose and PET Isotope Production for the TRIUMF Proton Therapy Facility

Abstract

Uveal melanoma is a rare and deadly tumour of the eye with primary metastases in the liver resulting in an 8% 2-year survival rate upon detection. Large growths, or those in close proximity to the optic nerve, pose a particular challenge to the commonly employed eye-sparing technique of eye-plaque brachytherapy. In these cases external beam charged particle therapy offers improved odds in avoiding catastrophic side effects such as neuropathy or blindness. Since 1995, the British Columbia Cancer Agency in partnership with the TRIUMF national laboratory have offered proton therapy in the treatment of difficult ocular tumors. Having seen 175 patients, yielding 80% globe preservation and 82% metastasis free survival as of 2010, this modality has proven to be highly effective. Despite this success, there have been few studies into the use of the world's largest cyclotron in patient care. Here we describe first efforts of modeling the TRIUMF dose delivery system using the FLUKA Monte Carlo package. Details on geometry, estimating beam parameters, measurement of primary dose and simulation of PET isotope production are discussed. Proton depth dose in both modulated and pristine beams is successfully simulated to sub-millimeter precision in range (within limits of measurement) and 2% agreement tomore » measurement within in a treatment volume. With the goal of using PET signals for in vivo dosimetry (alignment), a first look at PET isotope depth distribution is presented — comparing favourably to a naive method of approximating simulated PET slice activity in a Lucite phantom.« less

Authors:
;  [1]; ; ; ;  [2];  [3]
  1. University of Victoria (Australia)
  2. TRIUMF (Canada)
  3. University of British Columbia (Canada)
Publication Date:
OSTI Identifier:
22407710
Resource Type:
Journal Article
Resource Relation:
Journal Name: Medical Physics; Journal Volume: 41; Journal Issue: 8; Other Information: (c) 2014 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; BRACHYTHERAPY; COMPUTERIZED SIMULATION; DEPTH DOSE DISTRIBUTIONS; EYES; LUCITE; MELANOMAS; METASTASES; MONTE CARLO METHOD; POSITRON COMPUTED TOMOGRAPHY

Citation Formats

Lindsay, C, Jirasek, A, Blackmore, E, Hoehr, C, Schaffer, P, Trinczek, M, and Sossi, V. Sci—Fri PM: Topics — 07: Monte Carlo Simulation of Primary Dose and PET Isotope Production for the TRIUMF Proton Therapy Facility. United States: N. p., 2014. Web. doi:10.1118/1.4894954.
Lindsay, C, Jirasek, A, Blackmore, E, Hoehr, C, Schaffer, P, Trinczek, M, & Sossi, V. Sci—Fri PM: Topics — 07: Monte Carlo Simulation of Primary Dose and PET Isotope Production for the TRIUMF Proton Therapy Facility. United States. doi:10.1118/1.4894954.
Lindsay, C, Jirasek, A, Blackmore, E, Hoehr, C, Schaffer, P, Trinczek, M, and Sossi, V. Fri . "Sci—Fri PM: Topics — 07: Monte Carlo Simulation of Primary Dose and PET Isotope Production for the TRIUMF Proton Therapy Facility". United States. doi:10.1118/1.4894954.
@article{osti_22407710,
title = {Sci—Fri PM: Topics — 07: Monte Carlo Simulation of Primary Dose and PET Isotope Production for the TRIUMF Proton Therapy Facility},
author = {Lindsay, C and Jirasek, A and Blackmore, E and Hoehr, C and Schaffer, P and Trinczek, M and Sossi, V},
abstractNote = {Uveal melanoma is a rare and deadly tumour of the eye with primary metastases in the liver resulting in an 8% 2-year survival rate upon detection. Large growths, or those in close proximity to the optic nerve, pose a particular challenge to the commonly employed eye-sparing technique of eye-plaque brachytherapy. In these cases external beam charged particle therapy offers improved odds in avoiding catastrophic side effects such as neuropathy or blindness. Since 1995, the British Columbia Cancer Agency in partnership with the TRIUMF national laboratory have offered proton therapy in the treatment of difficult ocular tumors. Having seen 175 patients, yielding 80% globe preservation and 82% metastasis free survival as of 2010, this modality has proven to be highly effective. Despite this success, there have been few studies into the use of the world's largest cyclotron in patient care. Here we describe first efforts of modeling the TRIUMF dose delivery system using the FLUKA Monte Carlo package. Details on geometry, estimating beam parameters, measurement of primary dose and simulation of PET isotope production are discussed. Proton depth dose in both modulated and pristine beams is successfully simulated to sub-millimeter precision in range (within limits of measurement) and 2% agreement to measurement within in a treatment volume. With the goal of using PET signals for in vivo dosimetry (alignment), a first look at PET isotope depth distribution is presented — comparing favourably to a naive method of approximating simulated PET slice activity in a Lucite phantom.},
doi = {10.1118/1.4894954},
journal = {Medical Physics},
number = 8,
volume = 41,
place = {United States},
year = {Fri Aug 15 00:00:00 EDT 2014},
month = {Fri Aug 15 00:00:00 EDT 2014}
}
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