Methods for radiation dose distribution analysis and treatment planning in boron neutron capture therapy

Nigg, David W.

doi:10.1016/0360-3016(94)90486-3

Cited by 48 publications

(33 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Epithermal beams, with energies 0.5 eV to 10 keV, have better penetration in tissues. 1) Although the probability of reaction of an epithermal neutron with 10 B is much smaller than that of a thermal neutron, as they lose energy with tissue depth, they fall into the thermal range which is so much more effective in the boron neutron capture reaction. The peak of this thermalization of epithermal neutrons is about 3 cm in depth.…”

mentioning

confidence: 99%

The Effects of Boron Neutron Capture Therapy on Liver Tumors and Normal Hepatocytes in Mice

Suzuki

Masunaga

Kinashi

et al. 2000

Japanese Journal of Cancer Research

View full text Add to dashboard Cite

To explore the feasibility of employing boron neutron capture therapy (BNCT) to treat liver tumors, the effects of BNCT were investigated by using liver tumor models and normal hepatocytes in mice. Liver tumor models in C3H mice were developed by intrasplenic injection of SCCVII tumor cells. After borocaptate sodium (BSH) and boronophenylalanine (BPA) administration, 10 B concentrations were measured in tumors and liver and the liver was irradiated with thermal neutrons. The effects of BNCT on the tumor and normal hepatocytes were studied by using colony formation assay and micronucleus assay, respectively. To compare the effects of BSH-BNCT and BPA-BNCT, the compound biological effectiveness (CBE) factor was determined. The CBE factors for BSH on the tumor were 4.22 and 2.29 using D 10 and D 0 as endpoints, respectively. Those for BPA were 9.94 and 5.64. In the case of hepatocytes, the CBE factors for BSH and BPA were 0.94 and 4.25, respectively. Tumor-to-liver ratios of boron concentration following BSH and BPA administration were 0.3 and 2.8, respectively. Considering the accumulation ratios of 10 B, the therapeutic gain factors for BSH and BPA were 0.7-1.3 and 3.8-6.6, respectively. Therefore, it may be feasible to treat liver tumors with BPA-BNCT. Key words: BNCT -BSH -BPA -Liver tumorsVarious therapeutic options have been examined for the treatment of unresectable primary and secondary malignant tumors in the liver. These include percutaneous ethanol injection, intraarterial drug infusion, embolization, intraarterial chemoembolization and radiotherapy. However, the results of these treatments have not been satisfactory. In many cases there are multiple tumors, and the liver cannot tolerate large treatment volumes, especially in radiotherapy. Boron neutron capture therapy (BNCT) which combines an administration of a tumor-seeking boron compound with thermal neutron irradiation might be an effective treatment for malignant hepatic tumors for the following reasons. In the boron neutron capture reaction, 10 B absorbs a thermal neutron and releases two high linear energy transfer (LET) particles, an α particle and a 7 Li nucleus. These particles have path lengths of 9 and 4 µm, respectively, depositing all their energy within a range of about one cell diameter from the capture reaction site. Accordingly these high-LET particles have large relative biological effectiveness (RBE), and effective cell killing can be expected in malignant tumors, which are resistant to conventional radiotherapy using photons or electrons. The path lengths of these particles are so short that if tumor cells accumulate the boron compound selectively, only tumor cells can be killed.A major limitation in the application of BNCT using thermal neutrons is the tumor depth. Deep-seated tumors, such as hepatic tumors, are difficult to treat because of the poor penetration of thermal neutrons, which have energies <0.5 eV and a 15-16 mm half-value layer in water. Epithermal beams, with energies 0.5 eV to 10 keV, have better penetration in tiss...

show abstract

mentioning

confidence: 99%

The Effects of Boron Neutron Capture Therapy on Liver Tumors and Normal Hepatocytes in Mice

Suzuki

Masunaga

Kinashi

et al. 2000

Japanese Journal of Cancer Research

View full text Add to dashboard Cite

show abstract

“…The low neutron yield of the DD reaction is an obstacle for its use in this particular therapy. Neutrons from the Neutron source 3 H(d n) 4 He 2 H(d n) 3 He 7 Li(p n) 7 Be 7 Li(p n) 7 DT reaction could be moderated to around 10 keV without reducing the neutron ux to a negligible level. An equivalent tumor dose of 21.9 Gy-Eq could be achieved at a depth of 8 cm in the head pantom, which is about 50% higher than doses obtained by a neutron beam currently used at BMRR for clinical trials.…”

Section: Discussionmentioning

confidence: 99%

“…The optimal combination of materials that we came up with for DD was 30 cm of 7 LiF and 18 cm of 40%Al/60%AlF 3 . The BSA is 25 cm in diameter and surrounded by a thin (0.5 mm) layer of 6 …”

Section: Optimal Bsa and Dose Distribution For Ddmentioning

confidence: 99%

“…Reactions such a s 7 Li(p n), 9 Be(p n) a n d 9 Be(d n) are currently being investigated as accelerator-based neutron sources for BNCT because the energy of neutrons is of the order of hundreds of keV 2, 3,4]. The drawback o f these reactions is the high energy of the protons and deuterons required, which v aries usually between 2.3 and 4.0 MeV depending on the reaction, requiring a large accelerator and treatment facility.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Investigation of 2H(d,n) 3He and 3H(d,n) 4He Fusion Reactions as Alternative Neutron Sources for BNCT

Verbeke

Vujic

Leung

2001

Frontiers in Neutron Capture Therapy

View full text Add to dashboard Cite

Beam-shaping assemblies have been designed to moderate high energy neutrons from the fusion reactions 2 H (d n) 3 H e(DD) and 3 H (d n) 4 H e(DT) for use in Boron Neutron Capture Therapy. The low yield of DD is an obstacle for the treatment of Glioblastoma Multiforme. Our analysis shows that the high-energy neutrons from DT can be moderated to epithermal energy range without reducing the neutron ux to a negligible level. With the optimal beam-shaping assemb l y d e s i g n f o r D T , a 1 A deuteron beam with energy of 120 keV leads to a treatment time of 50 minutes. The dose near the center of the brain obtained with this con guration is about 50% higher than the dose from a typical spectrum produced by the Brookhaven Medical Research Reactor (BMRR), and is comparable to the dose obtained by other accelerator-produced neutron beams.

show abstract

“…Analyzing the transport of neutrons and photons through a head phantom is necessary to determine the clinical properties of a beam. This has been done in the second modeling stage using the Monte Carlo-based BNCT treatment planning code, "rtt-MC" [2]. The geometry and setup is depicted in figure 1.…”

Section: Moderator and Neutron Transport Modelingmentioning

confidence: 99%

Clinical requirements and accelerator concepts for BNCT

Ledewigt

Proceedings of the 1997 Particle Accelerator Conference (Cat. No.97CH36167)

View full text Add to dashboard Cite

Accelerator-based neutron sources are an attractive alternative to nuclear reactors for providing epithermal neutron beams for Boron Neutron Capture Therapy. Based on clinical requirements and neutronics modeling the use of proton and deuteron induced reactions in 7 Li and 9 Be targets has been compared. Excellent epithermal neutron beams can be produced via the 7 Li(p,n) 7 Be reaction at proton energies of ~2.5 MeV. An electrostatic quadrupole accelerator and a lithium target, which can deliver and handle 2.5 MeV protons at beam currents up to 50 mA, are under development for an accelerator-based

show abstract

Methods for radiation dose distribution analysis and treatment planning in boron neutron capture therapy

Cited by 48 publications

References 11 publications

The Effects of Boron Neutron Capture Therapy on Liver Tumors and Normal Hepatocytes in Mice

The Effects of Boron Neutron Capture Therapy on Liver Tumors and Normal Hepatocytes in Mice

Investigation of 2H(d,n) 3He and 3H(d,n) 4He Fusion Reactions as Alternative Neutron Sources for BNCT

Clinical requirements and accelerator concepts for BNCT

Contact Info

Product

Resources

About