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Niitsu H, Fukumitsu N, Tanaka K, Mizumoto M, Nakai K, Matsuda M, Ishikawa E, Hatano K, Hashimoto T, Kamizawa S, Sakurai H. Methyl- 11C-L-methionine positron emission tomography for radiotherapy planning for recurrent malignant glioma. Ann Nucl Med 2024; 38:305-314. [PMID: 38356008 PMCID: PMC10954960 DOI: 10.1007/s12149-024-01901-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 01/03/2024] [Indexed: 02/16/2024]
Abstract
OBJECTIVE To investigate differences in uptake regions between methyl-11C-L-methionine positron emission tomography (11C-MET PET) and gadolinium (Gd)-enhanced magnetic resonance imaging (MRI), and their impact on dose distribution, including changing of the threshold for tumor boundaries. METHODS Twenty consecutive patients with grade 3 or 4 glioma who had recurrence after postoperative radiotherapy (RT) between April 2016 and October 2017 were examined. The study was performed using simulation with the assumption that all patients received RT. The clinical target volume (CTV) was contoured using the Gd-enhanced region (CTV(Gd)), the tumor/normal tissue (T/N) ratios of 11C-MET PET of 1.3 and 2.0 (CTV (T/N 1.3), CTV (T/N 2.0)), and the PET-edge method (CTV(P-E)) for stereotactic RT planning. Differences among CTVs were evaluated. The brain dose at each CTV and the dose at each CTV defined by 11C-MET PET using MRI as the reference were evaluated. RESULTS The Jaccard index (JI) for concordance of CTV (Gd) with CTVs using 11C-MET PET was highest for CTV (T/N 2.0), with a value of 0.7. In a comparison of pixel values of MRI and PET, the correlation coefficient for cases with higher JI was significantly greater than that for lower JI cases (0.37 vs. 0.20, P = 0.007). D50% of the brain in RT planning using each CTV differed significantly (P = 0.03) and that using CTV (T/N 1.3) were higher than with use of CTV (Gd). V90% and V95% for each CTV differed in a simulation study for actual treatment using CTV (Gd) (P = 1.0 × 10-7 and 3.0 × 10-9, respectively) and those using CTV (T/N 1.3) and CTV (P-E) were lower than with CTV (Gd). CONCLUSIONS The region of 11C-MET accumulation is not necessarily consistent with and larger than the Gd-enhanced region. A change of the tumor boundary using 11C-MET PET can cause significant changes in doses to the brain and the CTV.
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Affiliation(s)
- Hikaru Niitsu
- Department of Radiation Oncology and Proton Medical Research Center, Faculty of Medicine, University of Tsukuba, 2-1-1 Amakubo, Tsukuba, Ibaraki, 305-8576, Japan.
| | - Nobuyoshi Fukumitsu
- Department of Radiation Oncology, Kobe Proton Center, 1-6-8, Minatoshima-Minamimachi, Kobe, 650-0047, Japan
| | - Keiichi Tanaka
- Department of Radiation Oncology and Proton Medical Research Center, Faculty of Medicine, University of Tsukuba, 2-1-1 Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
| | - Masashi Mizumoto
- Department of Radiation Oncology and Proton Medical Research Center, Faculty of Medicine, University of Tsukuba, 2-1-1 Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
| | - Kei Nakai
- Department of Radiation Oncology and Proton Medical Research Center, Faculty of Medicine, University of Tsukuba, 2-1-1 Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan
| | - Masahide Matsuda
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan
| | - Eiichi Ishikawa
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan
| | - Kentaro Hatano
- Department of Applied Molecular Imaging, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan
| | - Tsuyoshi Hashimoto
- Department of Radiology, AIC Imaging Center, 2-1-16 Amakubo, Tsukuba, Ibaraki, 305-0005, Japan
| | - Satoshi Kamizawa
- Department of Radiation Oncology and Proton Medical Research Center, Faculty of Medicine, University of Tsukuba, 2-1-1 Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
| | - Hideyuki Sakurai
- Department of Radiation Oncology and Proton Medical Research Center, Faculty of Medicine, University of Tsukuba, 2-1-1 Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
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Nitta H, Mizumoto M, Li Y, Oshiro Y, Fukushima H, Suzuki R, Hosaka S, Saito T, Numajiri H, Kawano C, Kamizawa S, Maruo K, Sakurai H. An analysis of muscle growth after proton beam therapy for pediatric cancer. J Radiat Res 2024; 65:251-255. [PMID: 38265112 PMCID: PMC10959433 DOI: 10.1093/jrr/rrad105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/20/2023] [Indexed: 01/25/2024]
Abstract
Retardation of growth and development is a well-known late effect after radiotherapy for pediatric patients. The goal of the study was to examine the effect of proton beam therapy (PBT) on the growth of muscles included in the irradiated area. The subjects were 17 pediatric patients (age ≤ 5 years) who received PBT with a treatment field including a muscle on only one side out of a pair of symmetrical bilateral muscles and had imaging evaluations for at least 1 year after PBT. The thicknesses of the irradiated and non-irradiated (contralateral) muscles were measured retrospectively on CT or MRI axial images collected before and after PBT. The change of thickness divided by the period (years) for each muscle was compared between the irradiated and contralateral sides. Correlations of muscle growth with irradiation dose and age at the start of treatment were also evaluated. The median observation period was 39.2 months. The measurement sites included the erector spinae (n = 9), gluteus maximus (n = 5) and rhomboids + trapezius (n = 3) muscles. The average changes in muscle thickness were 0.24 mm/year on the irradiated side and 1.19 mm/year on the contralateral side, showing significantly reduced growth on the irradiated side (P = 0.001). Younger patients had greater muscle growth. Irradiation dose was not significant, but muscle growth tended to decrease as the dose increased, and muscles irradiated at >50 Gy (RBE) showed little growth. These results show that muscle growth is affected by PBT and that long-term follow-up is needed to evaluate muscle growth retardation.
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Affiliation(s)
- Hazuki Nitta
- Department of Radiation Oncology, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Masashi Mizumoto
- Department of Radiation Oncology, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Yinuo Li
- Department of Radiation Oncology, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Yoshiko Oshiro
- Department of Radiation Oncology, Tsukuba Medical Center Hospital, 1-3-1 Amakubo, Tsukuba, Ibaraki, 305-8558, Japan
| | - Hiroko Fukushima
- Department of Pediatrics, University of Tsukuba Hospital, 2-1-1 Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
- Department of Child Health, Institute of Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Ryoko Suzuki
- Department of Pediatrics, University of Tsukuba Hospital, 2-1-1 Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
- Department of Child Health, Institute of Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Sho Hosaka
- Department of Pediatrics, University of Tsukuba Hospital, 2-1-1 Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
| | - Takashi Saito
- Department of Radiation Oncology, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Haruko Numajiri
- Department of Radiation Oncology, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Chie Kawano
- Department of Radiation Oncology, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Satoshi Kamizawa
- Department of Radiation Oncology, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Kazushi Maruo
- Department of Biostatistics, Institute of Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
| | - Hideyuki Sakurai
- Department of Radiation Oncology, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan
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Saito T, Mizumoto M, Oshiro Y, Miyamoto T, Kamizawa S, Nakamura M, Ishida T, Makishima H, Numajiri H, Nakai K, Sakae T, Sakurai H. Synchronization of light flash with the irradiation pulse in proton beam therapy: A case report. Tech Innov Patient Support Radiat Oncol 2023; 27:100218. [PMID: 37485049 PMCID: PMC10362298 DOI: 10.1016/j.tipsro.2023.100218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/26/2023] [Accepted: 07/06/2023] [Indexed: 07/25/2023] Open
Abstract
The correlation between sensory light flash and proton beam delivery was evaluated by measuring the timing of pulse beam delivery and light flash sensing using an event recorder in an 83-year-old patient receiving proton beam therapy (PBT) for nasopharyngeal adenoid cystic carcinoma. The treatment dose was 65 Gy (RBE) in 26 fractions with 2 ports, and both beams included the visual pathway (retina, optic nerve, chiasma). Measurements were obtained in 13 of the 26 fractions. The patient sensed a light flash in all 13 fractions and pressed the recorder button for 426 of the 430 pulsed beam deliveries, giving a sensing rate of 99.1%. The median duration of button-pressing of 0.3 s was almost the same as that of the beam pulse of 0.2 s, with a reaction time lag of 0.35 s. These results suggest a consistency between light flash during PBT and the timing of irradiation.
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Affiliation(s)
- Takashi Saito
- Department of Radiation Oncology, University of Tsukuba, Tsukuba, Japan
| | - Masashi Mizumoto
- Department of Radiation Oncology, University of Tsukuba, Tsukuba, Japan
| | - Yoshiko Oshiro
- Department of Radiation Oncology, University of Tsukuba, Tsukuba, Japan
- Department of Radiation Oncology, Tsukuba Medical Center Hospital, Tsukuba, Japan
| | - Toshio Miyamoto
- Department of Radiation Oncology, University of Tsukuba, Tsukuba, Japan
| | - Satoshi Kamizawa
- Department of Radiation Oncology, University of Tsukuba, Tsukuba, Japan
| | | | - Toshiki Ishida
- Department of Radiation Oncology, University of Tsukuba, Tsukuba, Japan
| | | | - Haruko Numajiri
- Department of Radiation Oncology, University of Tsukuba, Tsukuba, Japan
| | - Kei Nakai
- Department of Radiation Oncology, University of Tsukuba, Tsukuba, Japan
| | - Takeji Sakae
- Department of Radiation Oncology, University of Tsukuba, Tsukuba, Japan
| | - Hideyuki Sakurai
- Department of Radiation Oncology, University of Tsukuba, Tsukuba, Japan
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Sakae T, Takada K, Kamizawa S, Terunuma T, Ando K. Formulation of Time-Dependent Cell Survival with Saturable Repairability of Radiation Damage. Radiat Res 2023; 200:139-150. [PMID: 37303133 DOI: 10.1667/rade-21-00066.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 05/10/2023] [Indexed: 06/13/2023]
Abstract
This study aims to provide a model that compounds historically proposed ideas regarding cell survival irradiated with X rays or particles. The parameters used in this model have simple meanings and are closely related to cell death-related phenomena. The model is adaptable to a wide range of doses and dose rates and thus can consistently explain previously published cell survival data. The formulas of the model were derived by using five basic ideas: 1. "Poisson's law"; 2. "DNA affected damage"; 3. "repair"; 4. "clustered affected damage"; and 5. "saturation of reparability". The concept of affected damage is close to but not the same as the effect caused by the double-strand break (DSB). The parameters used in the formula are related to seven phenomena: 1. "linear coefficient of radiation dose"; 2. "probability of making affected damage"; 3. "cell-specific repairability", 4. "irreparable damage by adjacent affected damage"; 5. "recovery of temporally changed repairability"; 6. "recovery of simple damage which will make the affected damage"; 7. "cell division". By using the second parameter, this model includes cases where a single hit results in repairable-lethal and double-hit results in repairable-lethal. The fitting performance of the model for the experimental data was evaluated based on the Akaike information criterion, and practical results were obtained for the published experiments irradiated with a wide range of doses (up to several 10 Gy) and dose rates (0.17 Gy/h to 55.8 Gy/h). The direct association of parameters with cell death-related phenomena has made it possible to systematically fit survival data of different cell types and different radiation types by using crossover parameters.
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Affiliation(s)
- Takeji Sakae
- Faculty of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki, 305-8577, Japan
- University of Tsukuba Hospital, Proton Medical Research Center, 2-1-1, Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
| | - Kenta Takada
- Graduate School of Radiology, Gunma Prefectural College of Health Sciences, 323-1 Kamiokimachi, Maebashi, Gunma 371-0052, Japan
| | - Satoshi Kamizawa
- University of Tsukuba Hospital, Proton Medical Research Center, 2-1-1, Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
| | - Toshiyuki Terunuma
- Faculty of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki, 305-8577, Japan
- University of Tsukuba Hospital, Proton Medical Research Center, 2-1-1, Amakubo, Tsukuba, Ibaraki, 305-8576, Japan
| | - Koichi Ando
- Gunma University Heavy Ion Medical Center, 3-39, Showamachi, Maebashi, Gunma 371-0034, Japan
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Mori Y, Isobe T, Takei H, Miyazaki S, Kamizawa S, Tomita T, Kobayashi D, Sakurai H, Sakae T. Evaluation of basic characteristics of 3-mm dose equivalent measuring instrument for evaluating lens exposure dose in radiotherapy. J Med Radiat Sci 2023; 70:154-160. [PMID: 36811316 PMCID: PMC10258639 DOI: 10.1002/jmrs.653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 01/06/2023] [Indexed: 02/24/2023] Open
Abstract
INTRODUCTION Despite the development of DOSIRIS™, an eye lens dosimeter, the characteristics of DOSIRIS™ in the area of radiotherapy have not been investigated. The purpose of this study was to evaluate the basic characteristics of the 3-mm dose equivalent measuring instrument DOSIRIS™ in radiotherapy. METHODS Dose linearity and energy dependence were evaluated for the irradiation system based on the calibration method of the monitor dosimeter. The angle dependence was measured by irradiating from a total of 18 directions. Interdevice variation was repeated three times by simultaneously irradiating five dosimeters. The measurement accuracy was based on the absorbed dose measured by the monitor dosimeter of the radiotherapy equipment. Absorbed doses were converted to 3-mm dose equivalents and compared with DOSIRIS™ measurements. RESULTS Dose linearity was evaluated using the determination coefficient (R2 ) R2 = 0.9998 and 0.9996 at 6 and 10 MV, respectively. For energy dependence, although the therapeutic photons evaluated in this study had higher energies than in the previous studies and had a continuous spectrum, the response was equivalent to 0.2-1.25 MeV, well below the IEC 62387 limits. The maximum error at all angles was 15% (angle of 140°) and the coefficient of variation at all angles was 4.70%, which satisfies the standard of the thermoluminescent dosimeter measuring instrument. Accuracy of measurement was determined in terms of the measurement errors for DOSIRIS™ (3.2% and 4.3% at 6 and 10 MV, respectively,) using the 3-mm dose equivalent obtained from the theoretical value as a reference. The DOSIRIS™ measurements met the IEC standard which defines the measurement error of ±30% of the irradiance value in IEC 62387. CONCLUSIONS We found that the characteristics of the 3-mm dose equivalent dosimeter in a high-energy radiation satisfy the IEC standards and have the same measurement accuracy as diagnostic areas such as Interventional Radiology.
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Affiliation(s)
- Yutaro Mori
- Faculty of MedicineUniversity of TsukubaTsukubaJapan
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaJapan
| | - Tomonori Isobe
- Faculty of MedicineUniversity of TsukubaTsukubaJapan
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaJapan
| | - Hideyuki Takei
- Quantum Life and Medical Science DirectorateNational Institute for Quantum Science and TechnologyInage‐kuJapan
| | - Shohei Miyazaki
- Department of RadiologyUniversity of Tsukuba HospitalTsukubaJapan
| | - Satoshi Kamizawa
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaJapan
| | - Tetsuya Tomita
- Department of RadiologyUniversity of Tsukuba HospitalTsukubaJapan
| | | | - Hideyuki Sakurai
- Faculty of MedicineUniversity of TsukubaTsukubaJapan
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaJapan
| | - Takeji Sakae
- Faculty of MedicineUniversity of TsukubaTsukubaJapan
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaJapan
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Li Y, Mizumoto M, Oshiro Y, Nitta H, Saito T, Iizumi T, Kawano C, Yamaki Y, Fukushima H, Hosaka S, Maruo K, Kamizawa S, Sakurai H. A Retrospective Study of Renal Growth Changes after Proton Beam Therapy for Pediatric Malignant Tumor. Curr Oncol 2023; 30:1560-1570. [PMID: 36826081 PMCID: PMC9955816 DOI: 10.3390/curroncol30020120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/12/2023] [Accepted: 01/20/2023] [Indexed: 01/26/2023] Open
Abstract
The purpose of this study was to analyze renal late effects after proton beam therapy (PBT) for pediatric malignant tumors. A retrospective study was performed in 11 patients under 8 years of age who received PBT between 2013 and 2018. The kidney was exposed in irradiation of the primary lesion in all cases. Kidney volume and contour were measured on CT or MRI. Dose volume was calculated with a treatment-planning system. The median follow-up was 24 months (range, 11-57 months). In irradiated kidneys and control contralateral kidneys, the median volume changes were -5.63 (-20.54 to 7.20) and 5.23 (-2.01 to 16.73) mL/year; and the median % volume changes at 1 year were -8.55% (-47.52 to 15.51%) and 9.53% (-2.13 to 38.78%), respectively. The median relative volume change for irradiated kidneys at 1 year was -16.42% (-52.21 to -4.53%) relative to control kidneys. Kidneys irradiated with doses of 10, 20, 30, 40, and 50 GyE had volume reductions of 0.16%, 0.90%, 1.24%, 2.34%, and 8.2% per irradiated volume, respectively. The larger the irradiated volume, the greater the kidney volume was lost. Volume reduction was much greater in patients aged 4-7 years than in those aged 2-3 years. The results suggest that kidneys exposed to PBT in treatment of pediatric malignant tumor show continuous atrophy in follow-up. The degree of atrophy is increased with a higher radiation dose, greater irradiated volume, and older age. However, with growth and maturation, the contralateral kidney becomes progressively larger and is less affected by radiation.
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Affiliation(s)
- Yinuo Li
- Department of Radiation Oncology, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
| | - Masashi Mizumoto
- Department of Radiation Oncology, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
- Correspondence: ; Tel.: +81-29-853-7100; Fax: +81-29-853-7102
| | - Yoshiko Oshiro
- Department of Radiation Oncology, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
| | - Hazuki Nitta
- Department of Radiation Oncology, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
| | - Takashi Saito
- Department of Radiation Oncology, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
| | - Takashi Iizumi
- Department of Radiation Oncology, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
| | - Chie Kawano
- Department of Radiation Oncology, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
| | - Yuni Yamaki
- Department of Pediatrics, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
| | - Hiroko Fukushima
- Department of Pediatrics, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
| | - Sho Hosaka
- Department of Pediatrics, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
| | - Kazushi Maruo
- Department of Biostatistics, Faculty of Medicine, University of Tsukuba, Tsukuba 305-8575, Japan
| | - Satoshi Kamizawa
- Department of Radiation Oncology, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
| | - Hideyuki Sakurai
- Department of Radiation Oncology, University of Tsukuba Hospital, Tsukuba 305-8576, Japan
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Kobayashi D, Isobe T, Takada K, Mori Y, Takei H, Kumada H, Kamizawa S, Tomita T, Sato E, Yokota H, Sakae T. Establishment of a New Three-Dimensional Dose Evaluation Method Considering Variable Relative Biological Effectiveness and Dose Fractionation in Proton Therapy Combined with High-Dose-Rate Brachytherapy. J Med Phys 2020; 44:270-275. [PMID: 31908386 PMCID: PMC6936203 DOI: 10.4103/jmp.jmp_117_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 09/18/2019] [Accepted: 11/01/2019] [Indexed: 11/07/2022] Open
Abstract
Purpose: The purpose of this study is to evaluate the influence of variable relative biological effectiveness (RBE) of proton beam and dose fractionation has on dose distribution and to establish a new three-dimensional dose evaluation method for proton therapy combined with high-dose-rate (HDR) brachytherapy. Materials and Methods: To evaluate the influence of variable RBE and dose fractionation on dose distribution in proton beam therapy, the depth-dose distribution of proton therapy was compared with clinical dose, RBE-weighted dose, and equivalent dose in 2 Gy fractions using a linear-quadratic-linear model (EQD2LQL). The clinical dose was calculated by multiplying the physical dose by RBE of 1.1. The RBE-weighted dose is a biological dose that takes into account RBE variation calculated by microdosimetric kinetic model implemented in Monte Carlo code. The EQD2LQL is a biological dose that makes the RBE-weighted dose equivalent to 2 Gy using a linear-quadratic-linear (LQL) model. Finally, we evaluated the three-dimensional dose by taking into account RBE variation and LQL model for proton therapy combined with HDR brachytherapy. Results: The RBE-weighted dose increased at the distal of the spread-out Bragg peak (SOBP). With the difference in the dose fractionation taken into account, the EQD2LQL at the distal of the SOBP increased more than the RBE-weighted dose. In proton therapy combined with HDR brachytherapy, a divergence of 103% or more was observed between the conventional dose estimation method and the dose estimation method we propose. Conclusions: Our dose evaluation method can evaluate the EQD2LQL considering RBE changes in the dose distribution.
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Affiliation(s)
- Daisuke Kobayashi
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.,Department of Radiology, University of Tsukuba Hospital, Ibaraki, Japan
| | - Tomonori Isobe
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.,Faculty of Medicine, University of Tsukuba, Ibaraki, Japan.,Proton Medical Research Center, University of Tsukuba Hospital, Ibaraki, Japan
| | - Kenta Takada
- Graduate School of Radiological Technology, Gunma Prefectural College of Health Sciences, Gunma, Japan
| | - Yutaro Mori
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.,Faculty of Medicine, University of Tsukuba, Ibaraki, Japan.,Proton Medical Research Center, University of Tsukuba Hospital, Ibaraki, Japan
| | - Hideyuki Takei
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.,Faculty of Medicine, University of Tsukuba, Ibaraki, Japan.,Proton Medical Research Center, University of Tsukuba Hospital, Ibaraki, Japan
| | - Hiroaki Kumada
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.,Faculty of Medicine, University of Tsukuba, Ibaraki, Japan.,Proton Medical Research Center, University of Tsukuba Hospital, Ibaraki, Japan
| | - Satoshi Kamizawa
- Proton Medical Research Center, University of Tsukuba Hospital, Ibaraki, Japan
| | - Tetsuya Tomita
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.,Department of Radiology, University of Tsukuba Hospital, Ibaraki, Japan
| | - Eisuke Sato
- Faculty of Health Science, Juntendo University, Tokyo, Japan
| | - Hiroshi Yokota
- Department of Radiology, University of Tsukuba Hospital, Ibaraki, Japan
| | - Takeji Sakae
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.,Faculty of Medicine, University of Tsukuba, Ibaraki, Japan.,Proton Medical Research Center, University of Tsukuba Hospital, Ibaraki, Japan
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Koketsu J, Kumada H, Takada K, Takei H, Mori Y, Kamizawa S, Hu Y, Sakurai H, Sakae T. 3D-printable lung phantom for distal falloff verification of proton Bragg peak. J Appl Clin Med Phys 2019; 20:86-94. [PMID: 31538716 PMCID: PMC6753739 DOI: 10.1002/acm2.12706] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 07/19/2019] [Accepted: 08/02/2019] [Indexed: 11/25/2022] Open
Abstract
In proton therapy, the Bragg peak of a proton beam reportedly deteriorates when passing though heterogeneous structures such as human lungs. Previous studies have used heterogeneous random voxel phantoms, in which soft tissues and air are randomly allotted to render the phantoms the same density as human lungs, for conducting Monte Carlo (MC) simulations. However, measurements of these phantoms are complicated owing to their difficult‐to‐manufacture shape. In the present study, we used Voronoi tessellation to design a phantom that can be manufactured, and prepared a Voronoi lung phantom for which both measurement and MC calculations are possible. Our aim was to evaluate the effectiveness of this phantom as a new lung phantom for investigating proton beam Bragg peak deterioration. For this purpose, we measured and calculated the percentage depth dose and the distal falloff widths (DFW) passing through the phantom. For the 155 MeV beam, the measured and calculated DFW values with the Voronoi lung phantom were 0.40 and 0.39 cm, respectively. For the 200 MeV beam, the measured and calculated DFW values with the Voronoi lung phantom were both 0.48 cm. Our results indicate that both the measurements and MC calculations exhibited high reproducibility with plastinated lung sample from human body in previous studies. We found that better results were obtained using the Voronoi lung phantom than using other previous phantoms. The designed phantom may contribute significantly to the improvement of measurement precision. This study suggests that the Voronoi lung phantom is useful for simulating the effects of the heterogeneous structure of lungs on proton beam deterioration.
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Affiliation(s)
- Junichi Koketsu
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaIbarakiJapan
| | - Hiroaki Kumada
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaIbarakiJapan
- Faculty of MedicineUniversity of TsukubaTsukubaIbarakiJapan
| | - Kenta Takada
- Department of Radiological TechnologyGunma Prefectural College of Health SciencesMaebashiGunmaJapan
| | - Hideyuki Takei
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaIbarakiJapan
- Faculty of MedicineUniversity of TsukubaTsukubaIbarakiJapan
| | - Yutaro Mori
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaIbarakiJapan
- Faculty of MedicineUniversity of TsukubaTsukubaIbarakiJapan
| | - Satoshi Kamizawa
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaIbarakiJapan
| | - Yuchao Hu
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaIbarakiJapan
| | - Hideyuki Sakurai
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaIbarakiJapan
- Faculty of MedicineUniversity of TsukubaTsukubaIbarakiJapan
| | - Takeji Sakae
- Proton Medical Research CenterUniversity of Tsukuba HospitalTsukubaIbarakiJapan
- Faculty of MedicineUniversity of TsukubaTsukubaIbarakiJapan
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9
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Nakamura M, Fukumitsu N, Kamizawa S, Numajiri H, Nemoto Murofushi K, Ohnishi K, Aihara T, Ishikawa H, Okumura T, Tsuboi K, Sakurai H. A validated proton beam therapy patch-field protocol for effective treatment of large hepatocellular carcinoma. J Radiat Res 2018; 59:632-638. [PMID: 30085200 PMCID: PMC6151630 DOI: 10.1093/jrr/rry056] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 05/14/2018] [Indexed: 05/21/2023]
Abstract
Development of a curative local treatment for large hepatocellular carcinoma (HCC) is an important issue. Here, we investigated the dose homogeneity, safety and antitumor effectiveness of proton beam therapy (PBT) using a patch-field technique for large HCC. Data from nine patients (aged 52-79 years) with large HCC treated with patch-field PBT were investigated. The cranial-caudal diameters of the clinical target volumes (CTVs) were 15.0-18.6 cm (median 15.9). The CTV was divided cranially and caudally while both isocenters were aligned along the cranial-caudal axis and overlap of the cranial and caudal irradiation fields was set at 0-0.5 mm. Multileaf collimators were used to eliminate hot or cold spots. Total irradiation doses were 60-76.4 Gy equivalents. Irradiation doses as a percentage of the prescription dose (from the treatment planning system) around the junction were a minimum of 93-105%, a mean of 99-112%, and a maximum of 105-120%. Quality assurance (QA) was assessed in the cranial and caudal irradiation fields using imaging plates. Acute adverse effects of Grade 3 were observed in one patient (hypoalbuminemia), and a late adverse effect of Grade 3 was observed in one patient (liver abscess). Child-Pugh class elevations were observed in four patients (A to B: 3; B to C: 1). Overall survival rates at 1 and 2 years were 55 and 14%, respectively, with a median overall survival of 13.6 months. No patients showed local recurrence. Patch-field PBT supported by substantial QA therefore is one of the treatment options for large HCC.
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Affiliation(s)
- Masatoshi Nakamura
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
- Corresponding author. Proton Medical Research Center, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, 305–8575, Japan. Tel: +81-29-853-7100, Fax: +81-29-853-7102,
| | - Nobuyoshi Fukumitsu
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
| | - Satoshi Kamizawa
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
| | - Haruko Numajiri
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
| | - Keiko Nemoto Murofushi
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
| | - Kayoko Ohnishi
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
| | - Teruhito Aihara
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
| | - Hitoshi Ishikawa
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
| | - Toshiyuki Okumura
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
| | - Koji Tsuboi
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
| | - Hideyuki Sakurai
- Proton Medical Research Center, University of Tsukuba, Tsukuba, 1-1-1 Tennoudai, Tsukuba, Japan
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Takei H, Isobe T, Kitamura N, Mori Y, Tomita T, Kobayashi D, Kamizawa S, Sato T, Sakurai H, Sakae T. General ion recombination effect in a liquid ionization chamber in high-dose-rate pulsed photon and electron beams. J Radiat Res 2018; 59:282-285. [PMID: 29373670 PMCID: PMC5967456 DOI: 10.1093/jrr/rrx088] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/10/2017] [Indexed: 06/07/2023]
Abstract
Liquid ionization chambers (LICs) are highly sensitive to dose irradiation and have small perturbations because of their liquid-filled sensitive volume. They require a sensitive volume much smaller than conventional air-filled chambers. However, it has been reported that the collection efficiency has dependencies on the dose per pulse and the pulse repetition frequency of a pulsed beam. The purpose of this study was to evaluate in detail the dependency of the ion collection efficiency on the pulse repetition frequency. A microLion (PTW, Freiburg, Germany) LIC was exposed to photon and electron beams from a TrueBeam (Varian Medical Systems, Palo Alto, USA) linear accelerator. The pulse repetition frequency was varied, but the dose per pulse was fixed. A theoretical evaluation of the collection efficiency was performed based on Boag's theory. Linear correlations were observed between the frequency and the relative collection for all energies of the photon and electron beams. The decrease in the collected charge was within 1% for all the flattened photon and electron beams, and they were 1.1 and 1.8% for the 6 and 10 MV flattening filter-free photon beams, respectively. The theoretical ion collection efficiency was 0.990 for a 10 MV flattened photon beam with a dose rate of 3 Gy·min-1. It is suggested that the collected charge decreased because of the short time intervals of the beam pulse compared with the ion collection time. Thus, it is important to correctly choose the pulse repetition frequency, particularly when flattening filter-free mode is used for absolute dose measurements.
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Affiliation(s)
- Hideyuki Takei
- Proton Medical Research Center, University of Tsukuba Hospital, 2 Chome-1-1 Amakubo, Tsukuba, Ibaraki Prefecture 305-8576, Japan
- National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, 4-9-1 Anagawa, Inage, Chiba, Chiba 263-8555, Japan
| | - Tomonori Isobe
- Proton Medical Research Center, University of Tsukuba Hospital, 2 Chome-1-1 Amakubo, Tsukuba, Ibaraki Prefecture 305-8576, Japan
- Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Nozomi Kitamura
- Department of Radiation Oncology, The Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3 Chome-8-31 Ariake, Koto, Tokyo 135-0063, Japan
| | - Yutaro Mori
- Proton Medical Research Center, University of Tsukuba Hospital, 2 Chome-1-1 Amakubo, Tsukuba, Ibaraki Prefecture 305-8576, Japan
- Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Tetsuya Tomita
- Department of Radiology, University of Tsukuba Hospital, 2 Chome-1-1 Amakubo, Tsukuba, Ibaraki Prefecture 305-8576, Japan
| | - Daisuke Kobayashi
- Department of Radiology, University of Tsukuba Hospital, 2 Chome-1-1 Amakubo, Tsukuba, Ibaraki Prefecture 305-8576, Japan
| | - Satoshi Kamizawa
- Proton Medical Research Center, University of Tsukuba Hospital, 2 Chome-1-1 Amakubo, Tsukuba, Ibaraki Prefecture 305-8576, Japan
| | - Tomoharu Sato
- Department of Radiation Oncology, The Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3 Chome-8-31 Ariake, Koto, Tokyo 135-0063, Japan
| | - Hideyuki Sakurai
- Proton Medical Research Center, University of Tsukuba Hospital, 2 Chome-1-1 Amakubo, Tsukuba, Ibaraki Prefecture 305-8576, Japan
- Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Takeji Sakae
- Proton Medical Research Center, University of Tsukuba Hospital, 2 Chome-1-1 Amakubo, Tsukuba, Ibaraki Prefecture 305-8576, Japan
- Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
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11
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Tamura M, Sakurai H, Mizumoto M, Kamizawa S, Murayama S, Yamashita H, Takao S, Suzuki R, Shirato H, Ito YM. Lifetime attributable risk of radiation-induced secondary cancer from proton beam therapy compared with that of intensity-modulated X-ray therapy in randomly sampled pediatric cancer patients. J Radiat Res 2017; 58:363-371. [PMID: 27789564 PMCID: PMC5440886 DOI: 10.1093/jrr/rrw088] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 08/01/2016] [Accepted: 08/05/2016] [Indexed: 05/20/2023]
Abstract
To investigate the amount that radiation-induced secondary cancer would be reduced by using proton beam therapy (PBT) in place of intensity-modulated X-ray therapy (IMXT) in pediatric patients, we analyzed lifetime attributable risk (LAR) as an in silico surrogate marker of the secondary cancer after these treatments. From 242 pediatric patients with cancers who were treated with PBT, 26 patients were selected by random sampling after stratification into four categories: (i) brain, head and neck, (ii) thoracic, (iii) abdominal, and (iv) whole craniospinal (WCNS) irradiation. IMXT was replanned using the same computed tomography and region of interest. Using the dose-volume histograms (DVHs) of PBT and IMXT, the LARs of Schneider et al. were calculated for the same patient. All the published dose-response models were tested for the organs at risk. Calculation of the LARs of PBT and IMXT based on the DVHs was feasible for all patients. The means ± standard deviations of the cumulative LAR difference between PBT and IMXT for the four categories were (i) 1.02 ± 0.52% (n = 7, P = 0.0021), (ii) 23.3 ± 17.2% (n = 8, P = 0.0065), (iii) 16.6 ± 19.9% (n = 8, P = 0.0497) and (iv) 50.0 ± 21.1% (n = 3, P = 0.0274), respectively (one tailed t-test). The numbers needed to treat (NNT) were (i) 98.0, (ii) 4.3, (iii) 6.0 and (iv) 2.0 for WCNS, respectively. In pediatric patients who had undergone PBT, the LAR of PBT was significantly lower than the LAR of IMXT estimated by in silico modeling. Although a validation study is required, it is suggested that the LAR would be useful as an in silico surrogate marker of secondary cancer induced by different radiotherapy techniques.
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Affiliation(s)
- Masaya Tamura
- Department of Radiation Medicine, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, 060-8638, Japan
| | - Hideyuki Sakurai
- Proton Medical Research Center, University of Tsukuba, Amakubo 2-1-1, Tsukuba, 305-8576, Japan
| | - Masashi Mizumoto
- Proton Medical Research Center, University of Tsukuba, Amakubo 2-1-1, Tsukuba, 305-8576, Japan
| | - Satoshi Kamizawa
- Proton Medical Research Center, University of Tsukuba, Amakubo 2-1-1, Tsukuba, 305-8576, Japan
| | - Shigeyuki Murayama
- Proton Therapy Division, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka, 411-8777, Japan
| | - Haruo Yamashita
- Proton Therapy Division, Shizuoka Cancer Center Hospital, 1007 Shimonagakubo, Nagaizumi, Shizuoka, 411-8777, Japan
| | - Seishin Takao
- Department of Medical Physics, Hokkaido University Hospital, Kita 14, Nishi 5, Kita-ku, Sapporo, 060-8648, Japan
| | - Ryusuke Suzuki
- Department of Medical Physics, Hokkaido University Hospital, Kita 14, Nishi 5, Kita-ku, Sapporo, 060-8648, Japan
| | - Hiroki Shirato
- Department of Radiation Medicine, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, 060-8638, Japan
- Quantum Medical Science and Engineering, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, 060-8638, Japan
| | - Yoichi M. Ito
- Department of Biostatistics, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, 060-8638, Japan
- Corresponding author. Department of Biostatistics, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, 060-8638, Japan. Tel: +81-11-706-5896; Fax: +81-11-706-6050;
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12
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Isobe T, Okamoto Y, Hirano Y, Ando H, Takada K, Sato E, Shinoda K, Tadano K, Takei H, Kamizawa S, Mori Y, Suzuki H. Effect of biological factors on successful measurements with skeletal-muscle (1)H-MRS. Ther Clin Risk Manag 2016; 12:1133-7. [PMID: 27499626 PMCID: PMC4959760 DOI: 10.2147/tcrm.s84371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background Our purpose in this study was to clarify whether differences in subject group attributes could affect data acquisition in proton magnetic resonance spectroscopy (1H-MRS). Methods Subjects without diabetes mellitus (DM) were divided into two groups (group A, in their 20s; group B, 30–60 years old). Subjects with DM formed group C (30–60 years old). The numbers of subjects were 19, 27, and 22 for group A, B, and C respectively. For all subjects, 1H-MRS measurements were taken of the soleus muscle (SOL) and the anterior tibial muscle (AT). We defined the success of the measurements by the detection of intramyocellular lipids. Moreover, we also measured the full width at half maximum of the water peaks for all subjects. Results The success rate was significantly higher for the AT (100%) than for the SOL (81.6%) (P<0.01). For the SOL, the success rate was 100% in group A, 85.2% in group B, and 77.3% in group C. There was a significant difference (P<0.05) between groups A and B, as well as between groups A and C. In all subjects, there was a significant difference (P<0.01) in the full width at half maximum (Hz) of the water peak between the AT and SOL measurements. Conclusion We conclude that differences in the age and DM history of subjects could affect the probability of successful 1H-MRS data acquisition.
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Affiliation(s)
- Tomonori Isobe
- Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
| | | | - Yuji Hirano
- Department of Radiology, University of Tsukuba Hospital, Ibaraki, Japan
| | - Hiroki Ando
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan
| | - Kenta Takada
- Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Eisuke Sato
- Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, Tokyo, Japan
| | - Kazuya Shinoda
- Department of Radiology, Tsukuba Medical Center Hospital, Ibaraki, Japan
| | - Kiichi Tadano
- Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, Tokyo, Japan
| | - Hideyuki Takei
- Department of Radiology, University of Tsukuba Hospital, Ibaraki, Japan
| | | | - Yutaro Mori
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan
| | - Hiroaki Suzuki
- Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
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13
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Tamura M, Ito Y, Sakurai H, Mizumoto M, Kamizawa S, Murayama S, Yamashita H, Takao S, Suzuki R, Shirato H. SU-F-T-202: An Evaluation Method of Lifetime Attributable Risk for Comparing Between Proton Beam Therapy and Intensity Modulated X-Ray Therapy for Pediatric Cancer Patients by Averaging Four Dose-Response Models for Carcinoma Induction. Med Phys 2016. [DOI: 10.1118/1.4956339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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14
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Takada K, Kumada H, Isobe T, Terunuma T, Kamizawa S, Sakurai H, Sakae T, Matsumura A. Whole-body dose evaluation with an adaptive treatment planning system for boron neutron capture therapy. Radiat Prot Dosimetry 2015; 167:584-590. [PMID: 25520378 DOI: 10.1093/rpd/ncu357] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 11/19/2014] [Indexed: 06/04/2023]
Abstract
Dose evaluation for out-of-field organs during radiotherapy has gained interest in recent years. A team led by University of Tsukuba is currently implementing a project for advancing boron neutron capture therapy (BNCT), along with a radiation treatment planning system (RTPS). In this study, the authors used the RTPS (the 'Tsukuba-Plan') to evaluate the dose to out-of-field organs during BNCT. Computed tomography images of a whole-body phantom were imported into the RTPS, and a voxel model was constructed for the Monte Carlo calculations, which used the Particle and Heavy Ion Transport Code System. The results indicate that the thoracoabdominal organ dose during BNCT for a brain tumour and maxillary sinus tumour was 50-360 and 120-1160 mGy-Eq, respectively. These calculations required ∼29.6 h of computational time. This system can evaluate the out-of-field organ dose for BNCT irradiation during treatment planning with patient-specific irradiation conditions.
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Affiliation(s)
- Kenta Takada
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Hiroaki Kumada
- Faculty of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Tomonori Isobe
- Faculty of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Toshiyuki Terunuma
- Faculty of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Satoshi Kamizawa
- Faculty of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Hideyuki Sakurai
- Faculty of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Takeji Sakae
- Faculty of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Akira Matsumura
- Faculty of Medicine, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8575, Japan
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15
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Fuse H, Sakae T, Terunuma T, Kamizawa S, Segawa T, Yoshimura Y, Yamanashi K, Sato M, Sakurai H. [Experience using the isocenter verification device in proton therapy equipment]. Igaku Butsuri 2013; 33:166-170. [PMID: 24893491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this study, we developed an isocenter verification device for use in proton therapy. Radiation and mechanical isocenters were verified for treatment equipment including room lasers, a digital radiography system and the beam axis of a rotational gantry. The special feature of this device is its ability to correlate the position of the three isocenters in one measurement and thus improve accuracy compared to the conventional method using three separate devices. The reproducibility of the method and the fluctuation of the position of the beam axis isocenter were both investigated using this device for almost a year. Monthly measurements of the isocenter position were acquired for two gantries and it was found that the fluctuation was +/- 0.10mm for the up-to-down direction and +/- 0.16mm for the right-to-left direction in Gantry 1 and was +/-0.14mm for the up-to-down direction and +/-0.18mm for the right-to-left direction in Gantry 2. We could be measured with a repeatability of +/-0.18 mm or less by using developed device for the relative positional relationship between each isocenters. Because we can confirm results in approximately 30 minutes, we can perform a quality control after a clinical practice.
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