Accelerator-based epithermal neutron beam design for neutron capture therapy

Journal Article · Fri May 01 00:00:00 EDT 1992 · Medical Physics; (United States)

DOI:https://doi.org/10.1118/1.596815· OSTI ID:7109455

Yanch, J C; Zhou, X ^[1]; Shefer, R E; Klinkowstein, R E ^[2]

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1. Department of Nuclear Engineering and Whitaker College of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
2. Science Research Laboratory, Somerville, Massachusetts 02143 (United States)

Recent interest in the production of epithermal neutrons for use in boron neutron capture therapy (BNCT) has prompted an investigation into the feasibility of generating such neutrons with a high current proton accelerator. Energetic protons (2.5 MeV) on a {sup 7}Li target produce a spectrum of neutrons with maximum energy of roughly 800 keV. A number of combinations of D{sub 2}O moderator, lead reflector, {sup 6}Li thermal neutron filtration, and D{sub 2}O/ {sup 6}Li shielding will result in a useful epithermal flux of 1.6{times}10{sup 8} n/s at the patient position. The neutron beam is capable of delivering 3000 RBE-cGy to a tumor at a depth of 7.5 cm in a total treatment time of 60--93 min (depending on RBE values used and based on a 24-cm diameter{times}19-cm length D{sub 2}O moderator). Treatment of deeper tumors with therapeutic advantage would also be possible. Maximum advantage depths (RBE weighted) of 8.2--9.2 (again depending on RBE values and precise moderator configuration) are obtained in a right-circular cylindrical phantom composed of brain-equivalent material with an advantage ratio of 4.7--6.3. A tandem cascade accelerator (TCA), designed and constructed at Science Research Laboratory (SRL) in Somerville MA, can provide the required proton beam parameters for BNCT of deep-seated tumors. An optimized configuration of materials required to shift the accelerator neutron spectrum down to therapeutically useful energies has been designed using Monte Carlo simulation in the Whitaker College Biomedical Imaging and Computation Laboratory at MIT. Actual construction of the moderator/reflector assembly is currently underway.

• OSTI ID: 7109455
• Journal Information: Medical Physics; (United States), Vol. 19:3; ISSN 0094-2405
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
EPITHERMAL NEUTRONS
NEUTRON GENERATORS
NEUTRON CAPTURE THERAPY
TANDEM ELECTROSTATIC ACCELERATORS
NEUTRON FLUX
BORON 10
FEASIBILITY STUDIES
LITHIUM 7 TARGET
MEV RANGE 01-10
PROTON REACTIONS
ACCELERATORS
BARYON REACTIONS
BARYONS
BORON ISOTOPES
CHARGED-PARTICLE REACTIONS
ELECTROSTATIC ACCELERATORS
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
HADRON REACTIONS
HADRONS
ISOTOPES
LIGHT NUCLEI
MEDICINE
MEV RANGE
NEUTRON SOURCES
NEUTRON THERAPY
NEUTRONS
NUCLEAR MEDICINE
NUCLEAR REACTIONS
NUCLEI
NUCLEON REACTIONS
NUCLEONS
ODD-ODD NUCLEI
PARTICLE SOURCES
RADIATION FLUX
RADIATION SOURCES
RADIOLOGY
RADIOTHERAPY
STABLE ISOTOPES
TARGETS
THERAPY
430100* - Particle Accelerators- Design
Development
& Operation