Attenuator design for organs at risk in total body irradiation using a translation technique

2008 ◽  
Vol 35 (5) ◽  
pp. 1663-1669 ◽  
Author(s):  
Marie-Claude Lavallée ◽  
Sylviane Aubin ◽  
Mario Chrétien ◽  
Marie Larochelle ◽  
Luc Beaulieu
Keyword(s):  
At Risk ◽  
Total Body Irradiation ◽  
Organs At Risk ◽  
Translation Technique ◽  
Total Body

scholarly journals Optimized Conformal Total Body Irradiation Among Recipients of TCRαβ/CD19-Depleted Grafts in Pediatric Patients With Hematologic Malignancies: Single-Center Experience

2021 ◽  
Vol 11 ◽  
Author(s):  
Daria Kobyzeva ◽  
Larisa Shelikhova ◽  
Anna Loginova ◽  
Francheska Kanestri ◽  
Diana Tovmasyan ◽  
...  
Keyword(s):  
At Risk ◽  
Radiation Therapy ◽  
Dose Reduction ◽  
Total Body Irradiation ◽  
Pediatric Patients ◽  
Organs At Risk ◽  
Volumetric Modulated Arc Therapy ◽  
Arc Therapy ◽  
Total Body

Total body irradiation (TBI) in combination with chemotherapy is widely used as a conditioning regimen in pediatric and adult hematopoietic stem cell transplantation (HSCT). The combination of TBI with chemotherapy has demonstrated superior survival outcomes in patients with acute lymphoblastic and myeloid leukemia when compared with conditioning regimens based only on chemotherapy. The clinical application of intensity-modulated radiation therapy (IMRT)-based methods (volumetric modulated arc therapy (VMAT) and TomoTherapy) seems to be promising and has been actively used worldwide. The optimized conformal total body irradiation (OC-TBI) method described in this study provides selected dose reduction for organs at risk with respect to the most significant toxicity (lungs, kidneys, lenses). This study included 220 pediatric patients who received OC-TBI with subsequent chemotherapy and allogenic HSCT with TCRαβ/CD19 depletion. A group of 151 patients received OC-TBI using TomoTherapy, and 40 patients received OC-TBI using the Elekta Synergy™ linac with an Agility-MLC (Elekta, Crawley, UK) using volumetric modulated arc therapy (VMAT). Twenty-nine patients received OC-TBI with supplemental simultaneous boost to bone marrow—(SIB to BM) up to 15 Gy: 28 patients (pts)—TomoTherapy; one patient—VMAT. The follow-up duration ranged from 0.3 to 6.4 years (median follow-up, 2.8 years). Overall survival (OS) for all the patients was 63% (95% CI: 56–70), and event-free survival (EFS) was 58% (95% CI: 51–65). The cumulative incidence of transplant-related mortality (TRM) was 10.7% (95% CI: 2.2–16) for all patients. The incidence of early TRM (<100 days) was 5.0% (95% CI: 1.5–8.9), and that of late TRM (>100 days) was 5.7 (95% CI: 1.7–10.2). The main causes of death for all the patients were relapse and infection. The concept of OC-TBI using IMRT VMAT and helical treatment delivery on a TomoTherapy treatment unit provides maximum control of the dose distribution in extended targets with simultaneous dose reduction for organs at risk. This method demonstrated a low incidence of severe side effects after radiation therapy and predictable treatment effectiveness. Our initial experience demonstrates that OC-TBI appears to be a promising technique for the treatment of pediatric patients.

scholarly journals Total Body Irradiation as Conditioning Regimen for Haematopoietic Progenitor Cell Transplant: A Case Report and Literature Review

2020 ◽  
pp. 1-4
Author(s):  
Diana Alonso Sánchez ◽  
Diana Alonso Sánchez ◽  
Lloret Sáez- Bravo Marta
Keyword(s):  
At Risk ◽  
Total Body Irradiation ◽  
Progenitor Cell ◽  
Organs At Risk ◽  
Conditioning Regimen ◽  
Three Dimensional ◽  
Cell Transplant ◽  
Haematopoietic Progenitor Cell ◽  
Technological Advances ◽  
Total Body

This case study presents a young adult man with lymphoblastic leukaemia B who required total body irradiation (TBI) as a conditioning regimen for haematopoietic progenitor cell transplant (HPT) as the only curative treatment option for his oncological disease. TBI was carried out with personalised patient immobilisation, three-dimensional simulation, radiophysical planning and dosimetric calculations. A total of 12 Gy were prescribed to be administered twice a day for 3 days in a row by means of volumetric modulated intensity radiotherapy with several isocentres. The best technique for the administration of this radiotherapy is discussed because, although the clinical efficacy of the administration of this body dose has been well known for decades, technological advances have brought us new possibilities when compared to the traditional TBI (bilateral with horizontal photon beam and absorbent screen). These advances include the technique used in this case (multi-isocentre volumetric-radiotherapy), which allows a better doses distribution, reducing the dose in organs at risk (OARs) and producing less toxicity, and therefore allowing the inclusion of patients who would not tolerate a conventional TBI. In addition, this method would allow the dose to be scaled up locally in higher areas at risk with better results in the disease control.

scholarly journals Feasibility study of volumetric modulated arc therapy with Halcyon™ linac for total body irradiation

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Takuya Uehara ◽  
Hajime Monzen ◽  
Mikoto Tamura ◽  
Masahiro Inada ◽  
Masakazu Otsuka ◽  
...  
Keyword(s):  
Total Body Irradiation ◽  
Organs At Risk ◽  
Volumetric Modulated Arc Therapy ◽  
Dose Calculation ◽  
Target Volume ◽  
The Body ◽  
Whole Body ◽  
Data Set ◽  
Arc Therapy ◽  
Total Body

Abstract Background The use of total body irradiation (TBI) with linac-based volumetric modulated arc therapy (VMAT) has been steadily increasing. Helical tomotherapy has been applied in TBI and total marrow irradiation to reduce the dose to critical organs, especially the lungs. However, the methodology of TBI with Halcyon™ linac remains unclear. This study aimed to evaluate whether VMAT with Halcyon™ linac can be clinically used for TBI. Methods VMAT planning with Halcyon™ linac was conducted using a whole-body computed tomography data set. The planning target volume (PTV) included the body cropped 3 mm from the source. A dose of 12 Gy in six fractions was prescribed for 50% of the PTV. The organs at risk (OARs) included the lens, lungs, kidneys, and testes. Results The PTV D98%, D95%, D50%, and D2% were 8.9 (74.2%), 10.1 (84.2%), 12.6 (105%), and 14.2 Gy (118%), respectively. The homogeneity index was 0.42. For OARs, the Dmean of the lungs, kidneys, lens, and testes were 9.6, 8.5, 8.9, and 4.4 Gy, respectively. The V12Gy of the lungs and kidneys were 4.5% and 0%, respectively. The Dmax of the testes was 5.8 Gy. Contouring took 1–2 h. Dose calculation and optimization was performed for 3–4 h. Quality assurance (QA) took 2–3 h. The treatment duration was 23 min. Conclusions A planning study of TBI with Halcyon™ to set up VMAT-TBI, dosimetric evaluation, and pretreatment QA, was established.

scholarly journals Current practice in total-body irradiation: results of a Canada-wide survey

2017 ◽  
Vol 24 (3) ◽  
pp. 181 ◽  
Author(s):  
R.C.N. Studinski ◽  
D.J. Fraser ◽  
R.S. Samant ◽  
M.S. MacPherson
Keyword(s):  
Total Body Irradiation ◽  
Best Practice ◽  
Current Practice ◽  
Organs At Risk ◽  
Treatment Strategies ◽  
Marrow Transplant ◽  
Treatment Delivery ◽  
Current State ◽  
Total Body ◽  
Question Survey

Background Total-body irradiation (tbi) is used to condition patients before bone marrow transplant. A variety of tbi treatment strategies have been described and implemented, but no consensus on best practice has been reached. We report on the results of a survey created to assess the current state of tbi delivery in Canada.Results A 19-question survey was distributed to 49 radiation oncology programs in Canada. Responses were received from 20 centres, including 12 centres that perform tbi. A variety of tbi dose prescriptions was reported, although 12 Gy in 6 fractions was used in 11 of the 12 centres performing tbi. Half of the centres also reported using a dose prescription unique to their facility.Most centres use an extended-distance parallel-opposed-pair technique, with the patient standing or lying on a stretcher against a wall. Others translate the patient under the beam, sweep the beam over the patient, or use a more complicated multi-field technique. All but 1 centre indicated that they attenuate the lung dose; only 3 centres indicated attenuating the dose for other organs at risk. The survey also highlighted the considerable resources used for tbi, including extra staff, prolonged planning and treatment times, and use of locally developed hardware or software.Conclusions At transplant centres, tbi is commonly used, but there is no commonly accepted approach to planning and treatment delivery. The important discrepancies in practice between centres in Canada creates an opportunity to prompt more discussion and collaboration between centres, improving consistency and uniformity of practice.

scholarly journals Technical note: factors affecting dose distribution in the overlap region of two-segment total body irradiation by helical tomotherapy

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
HaiYang Wang ◽  
JunQi Liu ◽  
YiFei Pi ◽  
Qi Liu ◽  
Yang Mi ◽  
...  
Keyword(s):  
Total Body Irradiation ◽  
Dose Distribution ◽  
Helical Tomotherapy ◽  
Organs At Risk ◽  
Treatment Plan ◽  
Lead Wire ◽  
Slice Thickness ◽  
Height Range ◽  
Total Body ◽  
Overlap Region

Abstract Objective To assess the effects of various treatment planning parameters to identify the optimal gap distance for precise two-segment total body irradiation (TBI) using helical tomotherapy (HT) with fixed jaw mode. Methods and materials Data of a treatment plan for 8 acute leukemia patients (height range: 109–130 cm) were analyzed. All patients underwent total-body computed tomography (CT) with 5-mm slice thickness. A lead wire, placed at 10 cm above the patella, was used to mark the boundary between the two segments. Target volumes and organs at risk were delineated using a Varian Eclipse 10.0 physician’s workstation. Different distances between the lead wire and the boundary of the two targets were used. CT images were transferred to the HT workstation to design the treatment plans, by adjusting parameters, including the field width (FW; 2.5 cm, and 5 cm), pitch (0.287 and 0.430), modulation factor (1.8). The plans were superimposed to analyze the dose distributions in the overlap region when varying target gap distances, FWs, pitches to determine the optimal combinations. Results The pitch did not affect the dose distribution in the overlap region. The dose distribution in the overlap region was mostly homogeneous when the target gap distance was equal to the FW. Increased FW diminished the effect of the target gap distance on the heterogeneous index of the overlap region. Conclusions In two-segment TBI treatments by HT with Helix mode, a gap distance equal to the FW may achieve optimal dose distribution in the overlap region.

scholarly journals Non-Human Primates Receiving High-Dose Total-Body Irradiation are at Risk of Developing Cerebrovascular Injury Years Postirradiation

2020 ◽  
Vol 194 (3) ◽  
pp. 277
Author(s):  
Rachel N. Andrews ◽  
Ethan G. Bloomer ◽  
John D. Olson ◽  
David B. Hanbury ◽  
Gregory O. Dugan ◽  
...  
Keyword(s):  
At Risk ◽  
Total Body Irradiation ◽  
High Dose ◽  
Cerebrovascular Injury ◽  
Total Body

scholarly journals First Experience of Standard Linac, Rapid Arc and Dose-drop Scheme Based Total Body Irradiation

2020 ◽  
Author(s):  
Zhiyuan Xu ◽  
Li Yang ◽  
Tim Hui ◽  
Xiaoqin Jiang ◽  
Jeff chan ◽  
...  
Keyword(s):  
Real Time ◽  
Total Body Irradiation ◽  
Organs At Risk ◽  
Lymphocytic Leukemia ◽  
Dose Monitoring ◽  
Passing Rate ◽  
Target Volumes ◽  
Ct Simulation ◽  
Total Body ◽  
Time Dose

Abstract Background and purpose: To introduce a standard linac with true attachment free, rapid arc and dose-drop scheme for positioning related dose deviation control based total body irradiation(TBI).Materials/Methods: One eight years old girl diagnosed with acute lymphocytic leukemia underwent TBI in 2020. Target volumes and organs at risk were contoured after CT simulation. Total sixteen ARC and four AP-PA from five isocenters were designed. A dose-drop scheme on both sides of adjacent region were performed to reduce positioning-related dose deviation. A series of quality assurance before radiotherapy and real-time dose monitoring during radiotherapy were carried out.Results: The average on board imaging (OBI) time of per fraction was 40.3 min, the average beam on time of per fraction was 37.2 min, the average time to change from head first to feet first position was 18.4 min. The average mean lung dose was 9.89 Gy, the maximum lens dose was 7.60 Gy, the mean PTV_total dose was 12.17Gy, 98.23% PTV_total volume was covered by 90% of the prescription dose. The maximum dose (Dmax) of PTV_total was 13.65Gy. Dmean and V10.8 of PTV_total are only slightly different(0.49% - 1.89% and 0.26% - 1.04% respectively) even with an error of 5 - 20mm longitudinal misalignments. Gamma passing rate(3mm/ 3% Gamma criteria) are between 93.5% and 100%. Real-time dose monitoring showed an overall deviation of -3.9%±5.51%.Conclusions: Standard linac, rapid arc and dose-drop for positioning-related dose deviation control based total body irradiation is feasible, accurate, and reliable. It is worthy of clinical application.

513 Total body irradiation; the translation technique: the moving beam approach

2003 ◽  
Vol 1 (5) ◽  
pp. S156
Author(s):  
C. Zabatis ◽  
T. Koligliatis ◽  
S. Xenofos ◽  
K. Pistevou-Gobakis ◽  
E. Kypraiou ◽  
...  
Keyword(s):  
Total Body Irradiation ◽  
Translation Technique ◽  
Moving Beam ◽  
Total Body
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