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Nakashima, Hiroshi; Nakamura, Takemi; Kobayashi, Hitoshi*; Tanaka, Susumu*; Kumada, Hiroaki*
NEA/NSC/R(2021)2 (Internet), p.142 - 151, 2021/12
Aiming of development of facilities for boron neutron capture therapy (BNCT) that can be installed in hospitals, an accelerator-based BNCT facility is being developed at the Ibaraki Neutron Medical Research Center under a collaboration among the Japan Atomic Energy Agency, the High Energy Accelerator Research Organization, the University of Tsukuba, and other institutions. It consists of a proton accelerator, having a maximum beam power of 80 kW, and a target, moderator, collimator and shield (TMCS) system. For the design concept, to satisfy the BNCT beam conditions and achieve a low activation, the radiation behavior in the TMCS system was simulated by the Monte Carlo method and this system configuration was optimized accordingly. In addition, the radiation estimation of the TMCS system was verified via several experiments and its applicability for BNCT was proved. This report reviews the estimation and validation studies for the development of the accelerator-based BNCT facility.
Sato, Tatsuhiko; Hashimoto, Shintaro; Inaniwa, Taku*; Takada, Kenta*; Kumada, Hiroaki*
International Journal of Radiation Biology, 97(10), p.1450 - 1460, 2021/10
Times Cited Count：7 Percentile：77.21(Biology)The stochastic microdosimetric kinetic (SMK) model is one of the most sophisticated and precise models used in the estimation of the relative biological effectiveness of carbon-ion radiotherapy (CRT) and boron neutron capture therapy (BNCT). Through the introduction of Taylor expansion (TE) or fast Fourier transform (FFT), we developed two simplified SMK models and implemented them into the Particle and Heavy Ion Transport code System (PHITS). This study enables the instantaneous calculation of the equieffective dose for CRT and BNCT, considering their cellular-scale dose heterogeneities. Treatment-planning systems that use the improved PHITS as a dose-calculation engine are under development.
Ikebe, Yurie*; Oshima, Masumi*; Bamba, Shigeru*; Asai, Masato; Tsukada, Kazuaki; Sato, Tetsuya; Toyoshima, Atsushi*; Bi, C.*; Seto, Hirofumi*; Amano, Hikaru*; et al.
Applied Radiation and Isotopes, 164, p.109106_1 - 109106_7, 2020/10
Times Cited Count：2 Percentile：24.28(Chemistry, Inorganic & Nuclear)Boron Neutron Capture Therapy (BNCT) is a radiotherapy for the treatment of intractable cancer. In BNCT precise determination of 
B concentration in whole blood sample before neutron irradiation is crucial for control of the neutron irradiation time and the neutron dosimetry. We have applied the Charged Particle Activation Analysis (CPAA) to non-destructive and accurate determination of B concentration in whole blood sample. The experiment was performed at JAEA Tandem Accelerator using an 8 MeV proton beam. The 478 keV 
ray of 
Be produced in the B(p,
)Be reaction was used to quantify the B, and rays of 
Co originating from the reaction with Fe in blood was used to normalize the -ray intensity. The results demonstrated that the present CPAA method can be applied to the determination of the B concentration in the blood sample.
Takada, Kenta*; Sato, Tatsuhiko; Kumada, Hiroaki*; Sakurai, Hideyuki*; Sakae, Takeji*
Journal of Physics; Conference Series, 1662, p.012004_1 - 012004_6, 2020/10
The University of Tsukuba has developed a treatment planning system (TPS) for boron neutron capture therapy (BNCT) that uses a Monte Carlo algorithm as a dose calculation engine. In the system, RBE-weighted dose can be also estimated using the microdosimetric function implemented in PHITS. In this study, we calculated the RBE-weighted doses for various radiation therapy beams. Comparison between the calculated results for different radiation therapy beams as well as verification of the calculated data will be presented at the meeting.
Sato, Tatsuhiko; Masunaga, Shinichiro*; Kumada, Hiroaki*; Hamada, Nobuyuki*
Radiation Protection Dosimetry, 183(1-2), p.247 - 250, 2019/05
Times Cited Count：7 Percentile：61.94(Environmental Sciences)As an application of Particle and Heavy Ion Transport code System PHITS, We have developed the stochastic microdosimetric kinetic (SMK) model for estimating the therapeutic effects of various kinds of radiation therapy. In this study, we improved the SMK model for estimating the therapeutic effect of boron neutron capture therapy, BNCT. The improved SMK model can consider not only the intra- and intercellular heterogeneity of B-10 distribution but also the dose rate effect. The accuracy of the model was well verified by comparisons made between calculated and measured surviving fractions of tumor cells, which we previously determined in vivo in mice with B-10 compounds exposed to reactor neutron beam. Details of the improved SMK model together with the verification results will be presented at the meeting.
Saptiama, I.*; Kaneti, Y. V.*; Yuliarto, B.*; Kumada, Hiroaki*; Tsuchiya, Kunihiko; Fujita, Yoshitaka; Malgras, V.*; Fukumitsu, Nobuyoshi*; Sakae, Takeji*; Hatano, Kentaro*; et al.
Chemistry; A European Journal, 25(18), p.4843 - 4855, 2019/03
Times Cited Count：15 Percentile：55.35(Chemistry, Multidisciplinary)The effective utilization of various biomolecules for creating a series of mesoporous boehmite (-AlOOH) and gamma-alumina (-Al
O
) nanosheets with unique hierarchical multilayered structures is demonstrated. The nature and concentration of the biomolecules strongly influence the degree of the crystallinity, the morphology, and the textural properties of the resulting -AlOOH and -AlO nanosheets, allowing for easy tuning. The hierarchical -AlOOH and -AlO multilayered nanosheets synthesized by using biomolecules exhibit enhanced crystallinity, improved particle separation, and well-defined multilayered structures compared to those obtained without biomolecules. More impressively, these -AlOOH and -AlO nanosheets possess high surface areas up to 425 and 371 m
/g, respectively, due to their mesoporous nature and hierarchical multilayered structure. When employed for molybdenum adsorption toward medical radioisotope production, the hierarchical -AlO multilayered nanosheets exhibit Mo adsorption capacities of 33.1
40.8mg-Mo/g.
Fukumitsu, Nobuyoshi*; Yamauchi, Yusuke*; Saptiama, I.*; Ariga, Katsuhiko*; Hatano, Kentaro*; Kumada, Hiroaki*; Fujita, Yoshitaka; Tsuchiya, Kunihiko
Isotope News, (760), p.15 - 18, 2018/12
no abstracts in English
Takada, Kenta*; Sato, Tatsuhiko; Kumada, Hiroaki*; Koketsu, Junichi*; Takei, Hideyuki*; Sakurai, Hideyuki*; Sakae, Takeji*
Journal of Radiation Research, 59(1), p.91 - 99, 2018/01
Times Cited Count：34 Percentile：88.03(Biology)Evaluation of the relative biological effectiveness (RBE)-weighted dose is indispensable in the treatment planning of proton and carbon ion therapies. In this study, we validate the RBE-weighted dose calculated by microdosimetric kinetic model (MKM) in tandem with the Monte Carlo particle transport code PHITS for proton therapy using the full simulation geometry for the beam line of the Proton Medical Research Center at the University of Tsukuba. The physical dose and RBE-weighted dose on the central axis for a 155 MeV monoenergetic and spread-out Bragg peak beam of 60 mm width are evaluated by the method. The calculated results generally agree with the corresponding experimental data very well, though overestimations by approximately 3.2% and 15% at the maximum are observed for the physical and RBE-weighted doses, respectively. This research completes the computational microdosimetric approach based on a combination of PHITS and MKM for all types of radiotherapy that require RBE evaluations.
B distributionSato, Tatsuhiko; Masunaga, Shinichiro*; Kumada, Hiroaki*; Hamada, Nobuyuki*
Scientific Reports (Internet), 8(1), p.988_1 - 988_14, 2018/01
Times Cited Count：48 Percentile：93.3(Multidisciplinary Sciences)We here propose a new model for estimating the biological effectiveness for boron neutron capture therapy (BNCT) considering intra- and intercellular heterogeneity in B distribution. The new model was developed from our previously established stochastic microdosimetric kinetic model that determines the surviving fraction of cells irradiated with any radiations, their synergetic effect being taken into account. The model can predict the biological effectiveness of newly developed B compounds based on their intra- and intercellular distributions, and thus, it can play important roles not only in treatment planning but also in drug discovery research for future BNCT.
Naito, Fujio*; Anami, Shozo*; Ikegami, Kiyoshi*; Uota, Masahiko*; Ouchi, Toshikatsu*; Onishi, Takahiro*; Oba, Toshiyuki*; Obina, Takashi*; Kawamura, Masato*; Kumada, Hiroaki*; et al.
Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1244 - 1246, 2016/11
The proton linac installed in the Ibaraki Neutron Medical Research Center is used for production of the intense neutron flux for the Boron Neutron Capture Therapy (BNCT). The linac consists of the 3-MeV RFQ and the 8-MeV DTL. Design average beam current is 10mA. Target is made of Beryllium. First neutron production from the Beryllium target was observed at the end of 2015 with the low intensity beam as a demonstration. After the observation of neutron production, a lot of improvement s was carried out in order to increase the proton beam intensity for the real beam commissioning. The beam commissioning has been started on May 2016. The status of the commissioning is summarized in this report.
Nakamura, Takemi; Sakasai, Kaoru; Nakashima, Hiroshi; Takamiya, Koichi*; Kumada, Hiroaki*
Journal of Radiation Protection and Research, 41(2), p.105 - 109, 2016/06
no abstracts in English
Kondo, Yasuhiro; Hasegawa, Kazuo; Higashi, Yasuo*; Sugawara, Hirotaka*; Yoshioka, Masakazu*; Kumada, Hiroaki*; Matsumoto, Hiroshi*; Naito, Fujio*; Kurokawa, Shinichi*
Proceedings of 7th International Particle Accelerator Conference (IPAC '16) (Internet), p.906 - 909, 2016/06
An accelerator based boron neutron capture therapy (BNCT) facility is being planned at Okinawa institute of science and technology (OIST). The proton accelerator consists of a radio frequency quadrupole (RFQ) linac and a drift tube linac (DTL). The required beam power is 60 kW. The present beam energy and current are 10 MeV and 30 mA, respectively. The pulse length is 3.3 ms and the repetition rate is 60 Hz, therefore, the duty factor is 20%. In this paper, present design of this compact, medium current, high duty proton linac is presented.
Kondo, Yasuhiro; Hasegawa, Kazuo; Higashi, Yasuo*; Kumada, Hiroaki*; Kurokawa, Shinichi*; Matsumoto, Hiroshi*; Naito, Fujio*; Yoshioka, Masakazu*
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.948 - 950, 2015/09
An accelerator based boron neutron capture therapy (BNCT) facility is being planned at Okinawa institute of science and technology (OIST). The proton accelerator consists of a radio frequency quadrupole (RFQ) linac and a drift tube linac (DTL). The reqired beam power is 60 kW. The present beam energy and current are 10 MeV and 30 mA, respectively. The pulse length is 3.3 ms and the repetition rate is 60 Hz, therefore, the duty factor is 20%. In this paper, present designof this compact, midium current, high duty proton linac is presented.
Horiguchi, Hironori*; Sato, Tatsuhiko; Kumada, Hiroaki*; Yamamoto, Tetsuya*; Sakae, Takeji*
Journal of Radiation Research, 56(2), p.382 - 390, 2015/03
Times Cited Count：23 Percentile：69.26(Biology)For evaluating the irradiation effect in tumors and surrounding normal tissues in BNCT, it is of great importance to estimate the relative biological effectiveness (RBE) for each dose component in the same framework. We have therefore established a new method for estimating the RBE of all BNCT dose components on the basis of the microdosimetric kinetic model. This method employs the probability densities of lineal energy, y, in a subcellular structure as the index for expressing RBE, which can be calculated using the microdosimetric function implemented in the particle transport simulation code PHITS. The accuracy of this method was tested by comparing the calculated RBE values with corresponding measured data in a water phantom irradiated with an epithermal neutron beam. The calculation technique developed in this study will be useful for biological dose estimation in the treatment planning of BNCT.
Horiguchi, Hironori; Nakamura, Takemi; Kumada, Hiroaki*; Yanagie, Hironobu*; Suzuki, Minoru*; Sagawa, Hisashi
Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.234 - 237, 2010/10
Recurrent breast cancer has been considered the application for boron neutron capture therapy using the JRR-4. The investigation of irradiation conditions for the recurrent breast cancer was performed by simulation with the JCDS. We performed the preliminary dosimetry of the model to verify the efficient irradiation conditions such as the neutron energy modes and multiple field technique. From the result, when the 30 Gy-Eq dose as minimum dose was delivered to the cancers, comparable dose distribution was delivered at the healthy tissues by both a one-port irradiation from anterior direction and a two-port irradiation from tangential direction. We revealed that the two-port irradiation was not valid to reduce the healthy tissues dose due to the isotopic scattering of neutrons in the body. We concluded that the optimal irradiation condition was the one-port irradiation with thermal neutron beam mode in terms of less healthy tissues dose and shorter irradiation time.
Nakamura, Takemi; Horiguchi, Hironori; Kishi, Toshiaki; Motohashi, Jun; Sasajima, Fumio; Kumada, Hiroaki*
Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.379 - 382, 2010/10
The clinical trials of BNCT have been conducted using JRR-4. The JRR-4 stopped in January 2008, because the graphite reflector was considerably damaged. For this reason, the specifications of graphite reflectors were renewal. All existing graphite reflectors of JRR-4 were changed by new graphite reflectors. The resumption of JRR-4 was carried out with new graphite reflectors in February 2010. We measured the characteristics of neutron beam at the JRR-4 Neutron Beam Facility. A cylindrical water phantom was put the gap for 1cm from the beam port. TLD and gold wire were inserted within the phantom when the phantom was irradiated. The results of the measured thermal neutron flux and the dose in water were compared with MCNP calculations. The calculated results showed the same tendency with the experimental results. These results are proceeding well and will be reported in full paper at July 2010.
Kumada, Hiroaki*; Saito, Kimiaki; Nakamura, Takemi; Sakae, Takeji*; Sakurai, Hideyuki*; Matsumura, Akira*; Ono, Koji*
Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.238 - 241, 2010/10
Kumada, Hiroaki*; Nakamura, Takemi; Horiguchi, Hironori; Matsumura, Akira*
Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.414 - 417, 2010/10
Yanagie, Hironobu*; Kumada, Hiroaki*; Nakamura, Takemi; Higashi, Shushi*; Ikushima, Ichiro*; Morishita, Yasuyuki*; Shinohara, Atsuko*; Fujiwara, Mitsuteru*; Suzuki, Minoru*; Sakurai, Yoshinori*; et al.
Proceedings of 14th International Congress on Neutron Capture Therapy (ICNCT-14) (CD-ROM), p.157 - 160, 2010/10
Horiguchi, Hironori; Yamamoto, Kazuyoshi; Kishi, Toshiaki; Otake, Shinichi*; Kumada, Hiroaki*
JAEA-Research 2009-015, 38 Pages, 2009/07
JAEA-Research-2009-015.pdf:7.61MB
The boron neutron capture therapy (BNCT) has been conducted at JRR-4. There is an increased number of cases due to the expansion of application against head and neck cancer and skin cancer. Therefore, the BNCT requires the establishment of procedure to perform more cases in a day. The determination of boron concentration in blood is important to determine the prescribed dose given to a patient. Currently, prompt ray analysis (PGA) is applied to the determination of boron concentration. But the PGA is not applied to more than three times BNCT a day. Therefore, swiftness and precision method by inductively coupled plasma atomic emission spectrometry (ICP-AES) is studied. Using BSH for Boron standard of the ICP-AES, we enabled to analyze accurately without an intricate sample preparation. The measurement precision of the ICP-AES was within 5% by the correction factor based on the PGA. We established the method of swiftness determination of boron concentration in blood for BNCT.
