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Gruber I, Koelbl O, Treutwein M, Zeman F, Herr W, Holler E, Edinger M, Wolff D. Analysis of long-term mortality after total body irradiation-based and melphalan-based chemotherapy conditioning for acute myeloid leukemia. Ann Hematol 2023:10.1007/s00277-023-05318-y. [PMID: 37347269 DOI: 10.1007/s00277-023-05318-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 06/12/2023] [Indexed: 06/23/2023]
Abstract
Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative treatment option for selected patients with acute myeloid leukemia. Yet, the influence of total body irradiation (TBI)-based conditioning as compared to non-TBI-based conditioning on long-term mortality is unclear. We retrospectively evaluated outcomes after TBI-based (n = 91) and non-TBI-based conditioning (melphalan-based, n = 248) for 1st allo-HSCT patients transplanted at the University Hospital Regensburg between 1999 and 2020. TBI was performed with an average dose rate of 4 cGy/min. Median follow-up was 8.3 years (interquartile range, 4.8-12.9 years). Cumulative incidence rates of 5-year non-relapse mortality (NRM) were 17% (95% confidence interval, CI, 10-25) and 33% (95% CI, 27-40) after TBI- and non-TBI-based conditioning (P < 0.001). Five-year cumulative incidences of relapse (CIR) were 42% (95% CI, 32-52) and 29% (95% CI, 23-35) after TBI- and non-TBI-based conditioning (P = 0.030). The 5-year OS was 54% (95% CI, 43-64) and 55% (95% CI, 48-62) after TBI- and non-TBI-based conditioning. Both groups had similar 100-day acute graft-versus-host disease (aGVHD, 43% vs. 40%) and 5-year chronic GVHD (34% vs. 36%). The multivariable regression models found no associations of TBI with the outcomes NRM, CIR, PFS, OS, aGVHD, and cGVHD. TBI was no risk factor for NRM, even including mortality caused by secondary malignancies. NRM was influenced by patient age, advanced disease status, and the use of female donors for male recipients. TBI- and non-TBI-based conditioning appear to be equally effective and tolerable for AML patients eligible for 1st allo-HSCT.
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Affiliation(s)
- Isabella Gruber
- Department of Radiation Oncology, University Hospital Regensburg, Regensburg, Germany.
| | - Oliver Koelbl
- Department of Radiation Oncology, University Hospital Regensburg, Regensburg, Germany
| | - Marius Treutwein
- Department of Radiation Oncology, University Hospital Regensburg, Regensburg, Germany
| | - Florian Zeman
- Center for Clinical Studies, University Hospital Regensburg, Regensburg, Germany
| | - Wolfgang Herr
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
| | - Ernst Holler
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
| | - Matthias Edinger
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
- Leibniz Institute for Immunotherapy, Regensburg, Germany
| | - Daniel Wolff
- Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
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Misson-Yates S, Cunningham R, Gonzalez R, Diez P, Clark CH. Optimised conformal total body irradiation: a heterogeneous practice, so where next? Br J Radiol 2023; 96:20220650. [PMID: 36475820 PMCID: PMC10078861 DOI: 10.1259/bjr.20220650] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The use of volumetric arc therapy and inverse planning has been in routine use in radiotherapy for two decades. However, use in total body irradiation (TBI) has been more recent and few guidelines exist as to how to plan or verify. This has led to heterogeneous approaches. The goal of this review is to provide an overview of current advanced planning and dosimetry verification protocols used in optimised conformal TBI as a basis for investigating the need for greater standardisation in TBI.
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Affiliation(s)
- Sarah Misson-Yates
- Department of Medical Physics, Guy's Cancer Centre, Guy's and St Thomas' NHS Foundation Trust, London, UK
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, United Kingdom
| | - Rissa Cunningham
- Department of Medical Physics, Guy's Cancer Centre, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Regina Gonzalez
- Department of Medical Physics, Guy's Cancer Centre, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Patricia Diez
- Radiotherapy Physics, National Radiotherapy Trials Quality Assurance Group (RTTQA), Mount Vernon Cancer Centre, Northwood, UK
| | - Catharine H Clark
- Radiotherapy Physics, National Radiotherapy Trials Quality Assurance Group (RTTQA), Mount Vernon Cancer Centre, Northwood, UK
- Metrology for Medical Physics Centre, National Physical Laboratory, Teddington, UK
- Radiotherapy Physics, University College London Hospitals NHS Foundation Trust, London, UK
- Medical Physics and Bioengineering Department, University College London, London, UK
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3
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Gruber I, Koelbl O, Herr W, Holler E, Edinger M, Wolff D. Impact of chronic graft-versus-host disease on quality of life and cognitive function of long-term transplant survivors after allogeneic hematopoietic stem cell transplantation with total body irradiation. Radiat Oncol 2022; 17:195. [PMID: 36447269 PMCID: PMC9706937 DOI: 10.1186/s13014-022-02161-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 11/15/2022] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Total body irradiation (TBI)-based-conditioning before allogeneic hematopoietic stem cell transplantation (allo-HSCT) is standard of care in patients with acute myeloid leukemia (AML) but can cause long-term morbidity. Data on the impact of chronic Graft-versus-host disease (cGvHD) on cognitive function (CF) and quality of life (QoL) of long-term transplant survivors are sparse. METHODS We analyzed patient-reported outcomes focusing on progression-free AML patients and 1st allo-HSCT applying a standardized TBI-technique with an average dose rate of 4 cGy/min to the total body and lung shielding in case of doses > 8 Gy. Instruments included the Functional Assessment of Cancer Therapy-Bone marrow transplant (FACT-BMT, version 4), the FACT-Cognition Function (FACT-Cog, version 3) and the Patient Health Questionaire-4 (PHQ-4). We put focus on the impact of cGvHD and compared the results to normative data derived from the general population. RESULTS Out of 41 eligible patients contacted, 32 (78.0%) patients with a medium follow-up of 154 months (Interquartile range 113, 191 months) participated in the study. Eleven patients (34.4%) had active cGvHD, 11 (34.4%) resolved cGvHD and 10 (31.3%) never had cGvHD. Patients with active cGvHD had poorer FACT-BMT, FACT-Cog and higher PHQ-4 scores compared to patients with resolved cGvHD or who never had cGvHD. Outcomes were similar in patients with resolved cGvHD and those who never had cGvHD. Patients with active cGvHD had similar FACT-Cog, but lower FACT-BMT in comparison to normative data. However, the overall patient sample had similar FACT-BMT and FACT-Cog in comparison to normative data. CONCLUSION Our data indicate that CF of long-term survivors upon TBI-based allo-HSCT is not impaired, even in the presence of active cGvHD. However, active cGvHD has a negative impact on QoL. Trial registration The local Ethics Board of the University of Regensburg approved this study (Number 20-1810_1-101).
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Affiliation(s)
- Isabella Gruber
- grid.411941.80000 0000 9194 7179Department of Radiation Oncology, University Hospital Regensburg, Regensburg, Germany
| | - Oliver Koelbl
- grid.411941.80000 0000 9194 7179Department of Radiation Oncology, University Hospital Regensburg, Regensburg, Germany
| | - Wolfgang Herr
- grid.411941.80000 0000 9194 7179Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
| | - Ernst Holler
- grid.411941.80000 0000 9194 7179Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
| | - Matthias Edinger
- grid.411941.80000 0000 9194 7179Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany ,grid.515309.bLeibniz Institute for Immunotherapy, Regensburg, Germany
| | - Daniel Wolff
- grid.411941.80000 0000 9194 7179Department of Internal Medicine III, University Hospital Regensburg, Regensburg, Germany
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4
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Farag NM, Zaghloul MS, El-Gebaly RH, Hassan ZET, Hamza NM, Mohamad EA. A comprehensive method for calculating total body irradiation. J Med Imaging Radiat Sci 2022; 53:460-470. [DOI: 10.1016/j.jmir.2022.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 06/24/2022] [Accepted: 06/30/2022] [Indexed: 10/16/2022]
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5
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Maerz M, Treutwein M, Nabo J, Dobler B. Three-dimensional printers applied for the production of beam blocks in total body irradiation treatment. J Appl Clin Med Phys 2022; 23:e13592. [PMID: 35290701 PMCID: PMC9121048 DOI: 10.1002/acm2.13592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 01/20/2022] [Accepted: 03/01/2022] [Indexed: 12/02/2022] Open
Abstract
Purpose Total body irradiation (TBI) in extended source surface distance (SSD) is a common treatment technique before hematopoietic stem cell transplant. The lungs are organs at risk, which often are treated with a lower dose than the whole body. Methods This can be achieved by the application of blocks. Three‐dimensional (3D) printers are a modern tool to be used in the production process of these blocks. Results We demonstrate the applicability of a specific printer and printing material, describe the process, and evaluate the accuracy of the product. Conclusion The blocks and apertures were found to be applicable in clinical routine.
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Affiliation(s)
- Manuel Maerz
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Marius Treutwein
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
| | - Jan Nabo
- Department for Mathematics and Computer Science, Ostbayerische Technische Hochschule Regensburg, Regensburg, Germany
| | - Barbara Dobler
- Department of Radiotherapy, Regensburg University Medical Center, Regensburg, Germany
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6
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Aldrovandi LG, Farías RO, Mauri MF, Mairal ML. Commissioning of a three-dimensional arc-based technique for total body irradiation. J Appl Clin Med Phys 2021; 22:123-142. [PMID: 34258860 PMCID: PMC8425872 DOI: 10.1002/acm2.13355] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 03/25/2021] [Accepted: 06/16/2021] [Indexed: 11/24/2022] Open
Abstract
The purpose of this study is to describe the commissioning of a novel three‐dimensional arc‐based technique for total body irradiation (TBI) treatments. The development and implementation of this technique allowed our institution to transition from a bilateral two‐dimensional (2D) technique to a methodology based on volumetric dose calculation. The methodology described in this work is a derivation from the MATBI technique, with the static fields being replaced by four contiguous arc‐fields for each anterior and posterior incidence. The reduced number of fields we employed makes it possible to reach a satisfactory dose uniformity through manual optimization in a straightforward process. We use the Eclipse anisotropic analytical algorithm (AAA) algorithm, commissioned with preconfigured beam data for a 6 MV photon beam, at standard SSD (100 cm). A thorough evaluation of the accuracy of the AAA algorithm at an extended distance (approximately 200 cm) was carried out. For the evaluation, we compared measured and calculated percentage depth–dose and profiles that included open‐field, penumbra, and out‐of‐field regions. The analysis was performed for both static and arc fields, taking into consideration unshielded fields and also in the presence of lung shielding blocks. End‐to‐end tests were carried out for our institutional template plan by two means: with a 2D ion chamber array detector in solid phantom and using Gafchromic films in an anthropomorphic phantom. The results obtained in this work demonstrate that the Eclipse AAA algorithm commissioned for standard treatments can be safely used with our TBI planning technique. Moreover, this technique proved to be a highly efficient path to replace conventional treatment techniques, providing a homogeneous dose distribution, dosimetric robustness, and shorter treatment times. In addition, as inherited from the MATBI technique, our methodology can be implemented in small treatment rooms, with no need for ancillary equipment.
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Affiliation(s)
- León G Aldrovandi
- Departamento de Física Médica, Mevaterapia Oncología Radiante, Ciudad Autónoma de Buenos Aires, Argentina
| | - Rubén O Farías
- Departamento de Física Médica, Mevaterapia Oncología Radiante, Ciudad Autónoma de Buenos Aires, Argentina
| | - María F Mauri
- Departamento de Física Médica, Mevaterapia Oncología Radiante, Ciudad Autónoma de Buenos Aires, Argentina
| | - María L Mairal
- Departamento de Física Médica, Mevaterapia Oncología Radiante, Ciudad Autónoma de Buenos Aires, Argentina
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7
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Sabloff M, Tisseverasinghe S, Babadagli ME, Samant R. Total Body Irradiation for Hematopoietic Stem Cell Transplantation: What Can We Agree on? ACTA ACUST UNITED AC 2021; 28:903-917. [PMID: 33617507 PMCID: PMC7985756 DOI: 10.3390/curroncol28010089] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/19/2021] [Accepted: 02/02/2021] [Indexed: 01/23/2023]
Abstract
Total body irradiation (TBI), used as part of the conditioning regimen prior to allogeneic and autologous hematopoietic cell transplantation, is the delivery of a relatively homogeneous dose of radiation to the entire body. TBI has a dual role, being cytotoxic and immunosuppressive. This allows it to eliminate disease and create “space” in the marrow while also impairing the immune system from rejecting the foreign donor cells being transplanted. Advantages that TBI may have over chemotherapy alone are that it may achieve greater tumour cytotoxicity and better tissue penetration than chemotherapy as its delivery is independent of vascular supply and physiologic barriers such as renal and hepatic function. Therefore, the so-called “sanctuary” sites such as the central nervous system (CNS), testes, and orbits or other sites with limited blood supply are not off-limits to radiation. Nevertheless, TBI is hampered by challenging logistics of administration, coordination between hematology and radiation oncology departments, increased rates of acute treatment-related morbidity and mortality along with late toxicity to other tissues. Newer technologies and a better understanding of the biology and physics of TBI has allowed the field to develop novel delivery systems which may help to deliver radiation more safely while maintaining its efficacy. However, continued research and collaboration are needed to determine the best approaches for the use of TBI in the future.
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Affiliation(s)
- Mitchell Sabloff
- Division of Hematology, Department of Medicine, University of Ottawa, Ottawa, ON K1H 8L6, Canada;
- The Ottawa Hospital Research Institute, Ottawa, ON K1H 8L6, Canada
| | | | - Mustafa Ege Babadagli
- Division of Radiation Oncology, The Ottawa Hospital, Ottawa, ON K1H 8L6, Canada;
- Correspondence:
| | - Rajiv Samant
- Division of Radiation Oncology, The Ottawa Hospital, Ottawa, ON K1H 8L6, Canada;
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8
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Hoseinnezhad Zarghani E, Geraily G, Hadisinia T. Comparison of different TBI techniques in terms of dose homogeneity - review study. Cancer Radiother 2021; 25:380-389. [PMID: 33431295 DOI: 10.1016/j.canrad.2020.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 12/03/2020] [Accepted: 12/05/2020] [Indexed: 10/22/2022]
Abstract
Total body irradiation (TBI) is a kind of external beam radiotherapy, used in conjunction with chemotherapy with the purpose of immunosuppression. Since the target in TBI is the whole body, so achieving uniform dose distribution throughout the entire body during TBI is necessary. As recommended by AAPM dose variation must be within ±10% of the prescription dose. With the evidences from literature there is limited substantiation to consider a treatment method better than others, but with regard to the size of the treatment room, workload of the radiotherapy department and prevalent technology used within each treatment department it is recommended to make the suitable and optimum method in each department. In this work, a review study was performed on different TBI techniques with the purpose of assessment and comparison of dose distribution homogeneity in these methods.
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Affiliation(s)
- E Hoseinnezhad Zarghani
- Medical Physics and Engineering Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - G Geraily
- Medical Physics and Engineering Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Radiation Oncology Research Center, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran.
| | - T Hadisinia
- Medical Physics and Engineering Department, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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9
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Gieger TL, Nolan MW, Roback DM, Suter SE. Implementation of total body photon irradiation as part of an institutional bone marrow transplant program for the treatment of canine lymphoma and leukemias. Vet Radiol Ultrasound 2019; 60:586-593. [PMID: 31146304 DOI: 10.1111/vru.12776] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 04/16/2019] [Accepted: 04/17/2019] [Indexed: 11/27/2022] Open
Abstract
A total body irradiation (TBI) protocol was developed to support a bone marrow transplant (BMT) program for the treatment of canine hematologic malignancies. The purpose of this prospective study is to describe implementation of the protocol and resultant dosimetry. Nongraphic manual treatment planning using 6 MV photons, isocentric delivery, 40 × 40 cm field size, wall-mounted lasers to verify positioning, a lucite beam spoiler (without use of bolus material), a dose rate of 8.75 cGy/min at patient isocenter, and a source-to-axis distance of 338 cm were used for TBI. A monitor unit calculation formula was derived using ion chamber measurements and a solid water phantom. Five thermoluminescent dosimeters (TLDs) were used at various anatomic locations in each of four cadaver dogs, to verify fidelity of the monitor unit formula prior to clinical implementation. In vivo dosimetric data were then collected with five TLDs at various anatomic locations in six patients treated with TBI. A total dose of 10 Gy divided into two 5 Gy fractions was delivered approximately 16 h apart, immediately followed by autologous stem cell transplant. The mean difference between prescribed and delivered doses ranged from 99% to 109% for various sites in cadavers, and from 83% to 121% in clinical patients. The mean total body dose in cadavers and clinical patients when whole body dose was estimated by averaging doses measured by variably placed TLDs ranged from 98% to 108% and 93% to 102% of the prescribed dose, respectively, which was considered acceptable. This protocol could be used for institutional implementation of TBI.
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Affiliation(s)
- Tracy L Gieger
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina.,Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina
| | - Michael W Nolan
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina.,Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina.,Duke Cancer Institute, Durham, North Carolina
| | - Donald M Roback
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina.,Rex Cancer Center - UNC Rex Healthcare, Raleigh, North Carolina
| | - Steven E Suter
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina.,Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina.,Duke Cancer Institute, Durham, North Carolina.,Lineberger Comprehensive Cancer Center, Chapel Hill, North Carolina
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10
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Ishibashi N, Soejima T, Kawaguchi H, Akiba T, Hasegawa M, Isobe K, Ito H, Imai M, Ejima Y, Hata M, Sasai K, Shimoda E, Maebayashi T, Oguchi M, Akimoto T. National survey of myeloablative total body irradiation prior to hematopoietic stem cell transplantation in Japan: survey of the Japanese Radiation Oncology Study Group (JROSG). JOURNAL OF RADIATION RESEARCH 2018; 59:477-483. [PMID: 29584887 PMCID: PMC6054214 DOI: 10.1093/jrr/rry017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 12/15/2017] [Indexed: 06/08/2023]
Abstract
A myeloablative regimen that includes total-body irradiation (TBI) before hematopoietic stem cell transplantation results in higher patient survival rates than achieved with regimens without TBI. The TBI protocol, however, varies between institutions. In October 2015, the Japanese Radiation Oncology Study Group initiated a national survey of myeloablative TBI (covering 2010-2014). Among the 186 Japanese institutions performing TBI, 90 (48%) responded. The 82 institutions that had performed myeloablative TBI during this period treated 2698 patients with malignant disease [leukemia (2082 patients, 77.2%), malignant lymphoma (378, 14%)] and 37 with non-malignant disease [severe aplastic anemia (20, 54%), inborn errors of metabolism (5, 14%)]. A linear accelerator was used at all institutions. The institutions were divided into 41 large and 41 small institutions based on the median number of patients. The long source-surface distance technique was the method of choice in the 34 institutions (82.9%) and the moving-couch technique in the 7 (17.1%) in the large institutions. The schedules most routinely used by the participating institutions consisted of 12 Gy/6 fractions/3 days (26 institutions, 63.5%) in the large institutions. The dose rate varied from 5 to 26 cGy/min. The lungs and lenses were routinely shielded in 23 large institutions (56.1%), and only the lungs in 9 large institutions (21.9%). At lung-shielding institutions, the most frequent maximum acceptable total dose for the lungs was 8 Gy (19 institutions, 27.5%). Our results reveal considerable differences in the TBI methods used by Japanese institutions and thus the challenges in designing multicenter randomized trials based on TBI.
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Affiliation(s)
- Naoya Ishibashi
- Department of Radiology, Nihon University School of Medicine, 30-1 Oyaguchi Kami-cho, Itabashi-ku, Tokyo, Japan
| | - Toshinori Soejima
- Department of Radiation Oncology, Hyogo Cancer Center, Akashi, Japan
| | - Hiroki Kawaguchi
- Division of Radiation Oncology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takeshi Akiba
- Department of Radiation Oncology, Tokai University, School of Medicine, Isehara, Japan
| | - Masatoshi Hasegawa
- Department of Radiation Oncology, Nara Medical University, Kashihara, Japan
| | - Kouichi Isobe
- Department of Radiology, Toho University Sakura Medical Center, Chiba, Japan
| | - Hitoshi Ito
- Department of Radiation Oncology, Kyoto Katsura Hospital, Kyoto, Japan
| | - Michiko Imai
- Department of Radiation Oncology, Iwata City General Hospital, Shizuoka, Japan
| | - Yasuo Ejima
- Division of Radiation Oncology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Masaharu Hata
- Division of Radiation Oncology, Department of Oncology, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Keisuke Sasai
- Department of Radiation Oncology, Faculty of Medicine, Juntendo University, Tokyo, Japan
| | - Emiko Shimoda
- Department of Radiation Oncology, Nara Medical University, Kashihara, Japan
| | - Toshiya Maebayashi
- Department of Radiology, Nihon University School of Medicine, 30-1 Oyaguchi Kami-cho, Itabashi-ku, Tokyo, Japan
| | - Masahiko Oguchi
- Department of Radiation Oncology, Cancer Institute Hospital of Japanese Foundation for Cancer Research, Tokyo, Japan
| | - Tetsuo Akimoto
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Japan
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11
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Zhang R, Gao Y, Bai W. Quantification and comparison the dosimetric impact of two treatment couch model in VMAT. J Appl Clin Med Phys 2017; 19:10-16. [PMID: 29094802 PMCID: PMC5768035 DOI: 10.1002/acm2.12206] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 07/20/2017] [Accepted: 07/24/2017] [Indexed: 11/15/2022] Open
Abstract
The use of Monte Carlo treatment planning systems (TPS) in radiation therapy has increased the dosimetric accuracy of VMAT treatment sequences. However, this accuracy is compromised by not including the treatment couch into the treatment planning process. Therefore, the impact of the treatment couch on radiation delivery output was determined, and two different couch models (uniform couch model A vs two components model B) were included and tested in the Monaco TPS to investigate which model can better quantify the couch influence on radiation dose. Relative attenuation measurements were performed following procedures outlined by TG‐176 with three phantom positions for A–B direction: on the left half (L), in the center (C) and on the right half (R) of the couch. As well as absolute dose comparison of static fields of 10 × 10 cm2 that were delivered through the couch tops with that calculated in the TPS with the couch model at 2 mm and 5 mm computing grid size respectively. The most severe percentage deviation was 4.60% for the phantom positioned at the left half of the couch with 5 mm grid size at gantry angle 120°. The couch model was included in the TPS with a uniform ED of 0.26 g/cm3 or a two component model with a fiber 0.52 g/cm3 and foam core 0.1 g/cm3. After including the treatment couch, the maximum mean dose attenuation was reduced from 3.68% without couch included to (0.60, 0.83, 0.72, and 1.02) % for model A and model B at 2 and 5 mm voxel grid size. The results obtained showed that Model A performed better than the model B, demonstrating lower deviations from measurements and better robustness against dose grid resolution changes. Considering the results of this study, we propose the systematic introduction of the couch Model A in clinical routine. All the reported findings are valid for the Elekta iBEAM® evo Extension 415 couch and these methods can also be used for other couch model.
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Affiliation(s)
- Ruohui Zhang
- Department of Biomedical Engineering, Tianjin University, Tianjin, China.,Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China
| | - Yulan Gao
- Department of Gastroenterology, Hebei General Hospital, Shijiazhuang, China
| | - Wenwen Bai
- Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China
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