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Toward three-dimensional patient-specific internal dosimetry using GATE Monte Carlo technique. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Neira-Castro S, Guiu-Souto J, Pardo-Montero J. Dosimetry in positron emission tomography. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00026-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Deevband M, Mahmoudi E, Pirayesh E, Amoui M, Rad M. Comparison of accuracy in calculation of absorbed dose to the kidneys following radioligand therapy with 177Lu-DKFZ-PSMA-617 by two different background correction methods. Indian J Nucl Med 2022; 37:121-125. [PMID: 35982806 PMCID: PMC9380804 DOI: 10.4103/ijnm.ijnm_134_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 12/19/2021] [Accepted: 12/29/2021] [Indexed: 11/20/2022] Open
Abstract
Background: To improve the accuracy of activity image quality, scatter correction is a critical method. The aim of this study is to compare the accuracy in calculation of absorbed dose to patients following radioligand therapy (RLT) with 177Lu-DKFZ-PSMA-617 by two different methods of background correction in the conjugate view method. Materials and Methods: This study involved 10 patients. The individualized patient dosimetry calculations were based on whole-body planar scintigraphy images acquired in 10 patients with a mean age of 71.4 ± 6.07 years (range 63–85 years) at approximately 0–2 h, 4–6 h, 18–24 h, and 36–48 h after administration of the mean 6253 ± 826.4 MBq (range 5500–7400 MBq) of 177Lu-DKFZ-PSMA-617. Organ activities were calculated using the conjugate view method by Buijs and conventional background correction. Eventually, the absorbed dose of radiation was calculated using Medical Internal Radiation Dose formalism. Results: The dose per unit of injected activity (mGy/MBq) ± standard deviation for kidney using Buijs and conventional methods was 1.05 ± 0.11 and 0.63 ± 0.14, respectively. Conclusion: The Buijs background correction method was more accurate than the conventional method.
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Mahmoudi E, Pirayesh E, Deevband MR, Amoui M, Rad MG, Ghorbani M. Patient-Specific Dosimetry in Radioligand Therapy (RLT) for Metastatic Prostate Cancer Using 177Lu-DKFZ-PSMA-617. Nucl Med Mol Imaging 2021; 55:237-244. [PMID: 34721716 DOI: 10.1007/s13139-021-00713-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 07/30/2021] [Accepted: 08/16/2021] [Indexed: 11/26/2022] Open
Abstract
Purpose 177Lu-DKFZ-PSMA-617 is a promising treatment for patients with metastatic prostate cancer. Specific dosimetry for each patient is an important factor in planning the patient's treatment process. This study aimed to perform an image-based absorbed dose calculation for the treatment of metastatic prostate cancer with 177Lu-DKFZ-PSMA-617. Methods The individualized patient dosimetry calculations were based on whole-body planar scintigraphy images acquired in 10 patients with a mean age of 71.4 ± 6.07 years (range 63-85 years) at approximately 0-2 h, 4-6 h, 18-24 h, and 36-48 h after administration of the mean 6253 ± 826.4 MBq (range 5500-7400 MBq) of 177Lu-DKFZ-PSMA-617. Time-activity curves were generated for various organs. For count conversion to activities, calibration factors were calculated. Finally, the absorbed dose for an individual cycle was calculated using IDIAC-DOSE 2.1 software. Results On average, the calculated absorbed dose for the kidneys and salivary glands were 0.46 ± 0.09 mGy/MBq and 0.62 ± 0.07 mGy/MBq, respectively. Conclusions Based on the results, the177Lu-PSMA-617 therapy is a safe method for the treatment of castration-resistant prostate cancer patients. Large inter-individual variations in organ dose were found, demonstrating the need for patient-specific dosimetry and treatment planning.
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Affiliation(s)
- Elahe Mahmoudi
- Biomedical Engineering and Medical Physics Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Elahe Pirayesh
- Nuclear Medicine Department, Shohada-E-Tajrish Hospital, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Deevband
- Biomedical Engineering and Medical Physics Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mahasti Amoui
- Nuclear Medicine Department, Shohada-E-Tajrish Hospital, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Mahdi Ghorbani
- Biomedical Engineering and Medical Physics Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Asl RG, Sabbaghi R, Ahangari HT, Hejazi P, Foroutan M. Prediction of Absorbed Dose to Normal Organs with Endocrine Tumors for I-131 by use of 99mTC Single Photon Emission Computed Tomography/Computed Tomography and Geant4 Application for Tomographic Emission Simulation. Indian J Nucl Med 2021; 36:273-281. [PMID: 34658551 PMCID: PMC8481846 DOI: 10.4103/ijnm.ijnm_6_21] [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: 01/16/2021] [Revised: 04/30/2021] [Accepted: 05/07/2021] [Indexed: 11/04/2022] Open
Abstract
Introduction: This study aimed to predict the dose absorbed by normal organs with neuroendocrine tumors for 131I using single photon emission computed tomography/computed tomography (SPECT/CT) images and Geant4 application for tomographic emission (GATE) simulation. Materials and Methods: Four to 5 whole-body planar scan series, along with one SPECT/CT image, were taken from four patients following 99mTc-hynic-Tyr3-octreotide radiotracer injection. After image quantification, the residence time of each organ was calculated using the image analysis and the activity time curves. The energy deposit and dose conversion (S-value) were extracted from the GATE simulation for the target organs of each patient. Using the residence times and S-values, the mean absorbed dose for the target organs of each patient was calculated and compared with the data obtained from the standard method. Results: Very close agreement was obtained between the S-value of the self–organ irradiation. The mean percentage difference between the two methods (i.e. GATE and Medical Internal Radiation Dose [MIRD]) was 1.8%, while a weak agreement was observed for cross-organ irradiation. The percentage difference between the total absorbed doses by the organs was 2%. The percentage difference between the absorbed doses obtained for tumors and three considered normal organs estimated by the GATE method was slightly higher than the MIRD method (about 11% on average for tumors). Conclusion: Regardless of the small difference between the obtained results for the organs and absorbed doses of the tumors in the present study, patient-specific dosimetry by the GATE methods is useful and essential for therapeutic radionuclides such as 131I due to high cross-dose effects, especially for young adult patients, to ensure the radiation safety and increase the effectiveness of the treatment.
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Affiliation(s)
- Rohollah Ghahraman Asl
- Department of Medical Physics and Radiation Sciences, Faculty of Paramedicine, Sabzevar University of Medical Sciences, Sabzevar, Iran
| | - Rezvan Sabbaghi
- Department of Medical Physics, Faculty of medicine, Semnan University of Medical Sciences, Semnan, Iran
| | - Hadi Taleshi Ahangari
- Department of Medical Physics, Faculty of medicine, Semnan University of Medical Sciences, Semnan, Iran
| | - Payman Hejazi
- Department of Medical Physics, Faculty of medicine, Semnan University of Medical Sciences, Semnan, Iran
| | - Majid Foroutan
- Endocrinologist, Department of Internal Medicine, Faculty of Medicine, Semnan University of Medical Sciences, Semnan, Iran
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Kurth J, Heuschkel M, Tonn A, Schildt A, Hakenberg OW, Krause BJ, Schwarzenböck SM. Streamlined Schemes for Dosimetry of 177Lu-Labeled PSMA Targeting Radioligands in Therapy of Prostate Cancer. Cancers (Basel) 2021; 13:cancers13153884. [PMID: 34359784 PMCID: PMC8345627 DOI: 10.3390/cancers13153884] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/27/2021] [Accepted: 07/29/2021] [Indexed: 01/11/2023] Open
Abstract
Simple Summary In patients with progressive metastasized castration-resistance prostate cancer PSMA radioligand therapies have shown promising results regarding clinical safety and efficacy. Dosimetry is mandatory due to legal regulations and also required for the estimation of doses to organs at risk allowing for individual tailoring of treatment in PSMA-RLT. Due to those factors and the often poor health status of patients which restricts intense dosimetric imaging protocols, there is a clear need for simplified dosimetric approaches in mCRPC patients treated with [177Lu]Lu-PSMA-617. In this study, we evaluated different dosimetric methodologies and found that a streamlined dosimetric approach is feasible and valid. This approach is based on single time-point imaging at 48 h p.i. in cycle 2 to 6 taking into account kinetic results of a full dosimetric scheme performed only in cycle1. These results might have a relevant impact on patients handling regarding dosimetry during [177Lu]Lu-PSMA-617 radioligand therapy. Abstract (Background) Aim of this retrospective analysis was to investigate in mCRPC patients treated with [177Lu]Lu-PSMA-617 whether the absorbed dose (AD) in organs at risk (OAR, i.e., kidneys and parotid glands) can be calculated using simplified methodologies with sufficient accuracy. For this calculation, results and kinetics of the first therapy cycle were used. (Methods) 46 patients treated with 2 to 6 cycles of [177Lu]Lu-PSMA-617 were included. As reference (current clinical standard) full dosimetry of the OAR based on quantitative imaging (whole body scintigraphy and quantitative SPECT/CT at 2, 24, 48 and 72 h p.i.) for every cycle was used. Alternatively, two dosimetry schemes, simplified in terms of image acquisition and dose calculation, were established, both assuming nearly unchanged kinetics of the radiopharmaceutical for subsequent cycles. (Results) In general, for both OAR the simplified methods provided results that were consistent with the dosimetric reference method, both per cycle and in terms of cumulative AD. Best results were obtained when imaging was performed at 48 h p.i. in each of the subsequent cycles. However, both simplified methods tended to underestimate the cumulative AD. (Conclusion) Simplified dosimetry schemes are feasible to tailor multi-cycle [177Lu]Lu-PSMA-targeted therapies.
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Affiliation(s)
- Jens Kurth
- Department of Nuclear Medicine, Rostock University Medical Centre, 18057 Rostock, Germany; (M.H.); (A.T.); (A.S.); (B.J.K.); (S.M.S.)
- Correspondence: ; Tel.: +49-381-494-9101
| | - Martin Heuschkel
- Department of Nuclear Medicine, Rostock University Medical Centre, 18057 Rostock, Germany; (M.H.); (A.T.); (A.S.); (B.J.K.); (S.M.S.)
| | - Alexander Tonn
- Department of Nuclear Medicine, Rostock University Medical Centre, 18057 Rostock, Germany; (M.H.); (A.T.); (A.S.); (B.J.K.); (S.M.S.)
| | - Anna Schildt
- Department of Nuclear Medicine, Rostock University Medical Centre, 18057 Rostock, Germany; (M.H.); (A.T.); (A.S.); (B.J.K.); (S.M.S.)
- Core Facility Multimodal Small Animal Imaging, Rostock University Medical Centre, 18057 Rostock, Germany
| | - Oliver W. Hakenberg
- Department of Urology, Rostock University Medical Centre, 18057 Rostock, Germany;
| | - Bernd J. Krause
- Department of Nuclear Medicine, Rostock University Medical Centre, 18057 Rostock, Germany; (M.H.); (A.T.); (A.S.); (B.J.K.); (S.M.S.)
| | - Sarah M. Schwarzenböck
- Department of Nuclear Medicine, Rostock University Medical Centre, 18057 Rostock, Germany; (M.H.); (A.T.); (A.S.); (B.J.K.); (S.M.S.)
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Neira S, Guiu-Souto J, Pais P, Rodríguez Martínez de Llano S, Fernández C, Pubul V, Ruibal Á, Pombar M, Gago-Arias A, Pardo-Montero J. Quantification of internal dosimetry in PET patients II: Individualized Monte Carlo-based dosimetry for [18F]fluorocholine PET. Med Phys 2021; 48:5448-5458. [PMID: 34260065 PMCID: PMC9291792 DOI: 10.1002/mp.15090] [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: 03/04/2021] [Revised: 06/04/2021] [Accepted: 06/28/2021] [Indexed: 12/03/2022] Open
Abstract
Purpose To obtain individualized internal doses with a Monte Carlo (MC) method in patients undergoing diagnostic [18F]FCH‐PET studies and to compare such doses with the MIRD method calculations. Methods A patient cohort of 17 males were imaged after intravenous administration of a mean [18F]FCH activity of 244.3 MBq. The resulting PET/CT images were processed in order to generate individualized input source and geometry files for dose computation with the MC tool GATE. The resulting dose estimates were studied and compared to the MIRD method with two different computational phantoms. Mass correction of the S‐factors was applied when possible. Potential sources of uncertainty were closely examined: the effect of partial body images, urinary bladder emptying, and biokinetic modeling. Results Large differences in doses between our methodology and the MIRD method were found, generally in the range ±25%, and up to ±120% for some cases. The mass scaling showed improvements, especially for non‐walled and high‐uptake tissues. Simulations of the urinary bladder emptying showed negligible effects on doses to other organs, with the exception of the prostate. Dosimetry based on partial PET/CT images (excluding the legs) resulted in an overestimation of mean doses to bone, skin, and remaining tissues, and minor differences in other organs/tissues. Estimated uncertainties associated with the biokinetics of FCH introduce variations of cumulated activities in the range of ±10% in the high‐uptake organs. Conclusions The MC methodology allows for a higher degree of dosimetry individualization than the MIRD methodology, which in some cases leads to important differences in dose values. Dosimetry of FCH‐PET based on a single partial PET study seems viable due to the particular biokinetics of FCH, even though some correction factors may need to be applied to estimate mean skin/bone doses.
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Affiliation(s)
- Sara Neira
- Group of Medical Physics and Biomathematics, Instituto de Investigación Sanitaria de Santiago, Santiago de Compostela, Spain
| | - Jacobo Guiu-Souto
- Department of Medical Physics, Centro Oncolóxico de Galicia, A Coruña, Spain
| | - Paulino Pais
- Department of Nuclear Medicine, Centro Oncolóxico de Galicia, A Coruña, Spain
| | | | - Carlos Fernández
- Department of Medical Physics, Centro Oncolóxico de Galicia, A Coruña, Spain
| | - Virginia Pubul
- Department of Nuclear Medicine, Complexo Hospitalario Universitario de Santiago de Compostela, Santiago de Compostela, Spain
| | - Álvaro Ruibal
- Department of Nuclear Medicine, Complexo Hospitalario Universitario de Santiago de Compostela, Santiago de Compostela, Spain.,Group of Molecular Imaging and Oncology, Instituto de Investigación Sanitaria de Santiago, Santiago de Compostela, Spain.,Molecular Imaging Group, Department of Radiology, Faculty of Medicine, Universidade de Santiago de Compostela, Santiago de Compostela, Spain.,Fundación Tejerina, Madrid, Spain
| | - Miguel Pombar
- Group of Molecular Imaging and Oncology, Instituto de Investigación Sanitaria de Santiago, Santiago de Compostela, Spain.,Department of Medical Physics, Complexo Hospitalario Universitario de Santiago de Compostela, Santiago de Compostela, Spain
| | - Araceli Gago-Arias
- Group of Medical Physics and Biomathematics, Instituto de Investigación Sanitaria de Santiago, Santiago de Compostela, Spain.,Department of Medical Physics, Complexo Hospitalario Universitario de Santiago de Compostela, Santiago de Compostela, Spain.,Institute of Physics, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Juan Pardo-Montero
- Group of Medical Physics and Biomathematics, Instituto de Investigación Sanitaria de Santiago, Santiago de Compostela, Spain.,Department of Medical Physics, Complexo Hospitalario Universitario de Santiago de Compostela, Santiago de Compostela, Spain
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Brosch-Lenz J, Uribe C, Gosewisch A, Kaiser L, Todica A, Ilhan H, Gildehaus FJ, Bartenstein P, Rahmim A, Celler A, Ziegler S, Böning G. Influence of dosimetry method on bone lesion absorbed dose estimates in PSMA therapy: application to mCRPC patients receiving Lu-177-PSMA-I&T. EJNMMI Phys 2021; 8:26. [PMID: 33709253 PMCID: PMC7952490 DOI: 10.1186/s40658-021-00369-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 02/23/2021] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Patients with metastatic, castration-resistant prostate cancer (mCRPC) present with an increased tumor burden in the skeleton. For these patients, Lutetium-177 (Lu-177) radioligand therapy targeting the prostate-specific membrane antigen (PSMA) has gained increasing interest with promising outcome data. Patient-individualized dosimetry enables improvement of therapy success with the aim of minimizing absorbed dose to organs at risk while maximizing absorbed dose to tumors. Different dosimetric approaches with varying complexity and accuracy exist for this purpose. The Medical Internal Radiation Dose (MIRD) formalism applied to tumors assumes a homogeneous activity distribution in a sphere with unit density for derivation of tumor S values (TSV). Voxel S value (VSV) approaches can account for heterogeneous activities but are simulated for a specific tissue. Full patient-individual Monte Carlo (MC) absorbed dose simulation addresses both, heterogeneous activity and density distributions. Subsequent CT-based density weighting has the potential to overcome the assumption of homogeneous density in the MIRD formalism with TSV and VSV methods, which could be a major limitation for the application in bone metastases with heterogeneous density. The aim of this investigation is a comparison of these methods for bone lesion dosimetry in mCRPC patients receiving Lu-177-PSMA therapy. RESULTS In total, 289 bone lesions in 15 mCRPC patients were analyzed. Percentage difference (PD) of average absorbed dose per lesion compared to MC, averaged over all lesions, was + 14 ± 10% (min: - 21%; max: + 56%) for TSVs. With lesion-individual density weighting using Hounsfield Unit (HU)-to-density conversion on the patient's CT image, PD was reduced to - 8 ± 1% (min: - 10%; max: - 3%). PD on a voxel level for three-dimensional (3D) voxel-wise dosimetry methods, averaged per lesion, revealed large PDs of + 18 ± 11% (min: - 27%; max: + 58%) for a soft tissue VSV approach compared to MC; after voxel-wise density correction, this was reduced to - 5 ± 1% (min: - 12%; max: - 2%). CONCLUSION Patient-individual MC absorbed dose simulation is capable to account for heterogeneous densities in bone lesions. Since the computational effort prevents its routine clinical application, TSV or VSV dosimetry approaches are used. This study showed the necessity of lesion-individual density weighting for TSV or VSV in Lu-177-PSMA therapy bone lesion dosimetry.
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Affiliation(s)
- Julia Brosch-Lenz
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Carlos Uribe
- PET Functional Imaging, BC Cancer, 600 West 10th Avenue, Vancouver, BC V5Z 4E6 Canada
- Department of Radiology, University of British Columbia, 2775 Laurel Street, Vancouver, BC V5Z 1M9 Canada
| | - Astrid Gosewisch
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Lena Kaiser
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Andrei Todica
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Harun Ilhan
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Franz Josef Gildehaus
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Peter Bartenstein
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Arman Rahmim
- PET Functional Imaging, BC Cancer, 600 West 10th Avenue, Vancouver, BC V5Z 4E6 Canada
- Department of Radiology, University of British Columbia, 2775 Laurel Street, Vancouver, BC V5Z 1M9 Canada
- Department of Integrative Oncology, BC Cancer Research Centre, 675 West 10th Avenue, Vancouver, BC V5Z 1L3 Canada
| | - Anna Celler
- Department of Radiology, University of British Columbia, 2775 Laurel Street, Vancouver, BC V5Z 1M9 Canada
| | - Sibylle Ziegler
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Guido Böning
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
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Flux G, Murray I, Rushforth D, Gape P, Abreu C, Lee M, Ribeiro A, Gregory R, Chittenden S, Thurston J, Du Y, Gear J. SOLLID - a single centre study to develop methods to investigate the effects of low radiation doses within nuclear medicine, to enable multicentre epidemiological investigations. Br J Radiol 2021; 94:20200072. [PMID: 32903035 PMCID: PMC8011250 DOI: 10.1259/bjr.20200072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 08/17/2020] [Accepted: 08/20/2020] [Indexed: 02/01/2023] Open
Abstract
There is continuing debate concerning the risks of secondary malignancies from low levels of radiation exposure. The current model used for radiation protection is predicated on the assumption that even very low levels of exposure may entail risk. This has profound implications for medical procedures involving ionising radiation as radiation doses must be carefully monitored, and for diagnostic procedures are minimised as far as possible. This incurs considerable expense. The SOLLID study (ClinicalTrials.gov Identifier: NCT03580161) aims to develop the methodology to enable a large-scale epidemiological investigation of the effect of radiopharmaceutical administrations to patients undergoing diagnostic nuclear medicine procedures. Patients will undergo a series of scans in addition to that acquired as standard of care to enable the radiation doses delivered to healthy organs to be accurately calculated. Detailed analysis will be performed to determine the uncertainty in the radiation dose calculations as a function of the number and type of scans acquired. It is intended that this will inform a subsequent long-term multicentre epidemiological study that would address the question definitively. Secondary aims of the study are to evaluate the range of absorbed doses that are delivered from diagnostic nuclear medicine procedures and to use current risk models to ascertain the relative risks from these administrations.
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Affiliation(s)
- Glenn Flux
- Department of Physics, Royal Marsden Hospital, Downs Road, Sutton, Surrey, United Kingdom
| | - Iain Murray
- Department of Physics, Royal Marsden Hospital, Downs Road, Sutton, Surrey, United Kingdom
| | - Dominic Rushforth
- Department of Physics, Royal Marsden Hospital, Downs Road, Sutton, Surrey, United Kingdom
| | - Paul Gape
- Department of Physics, Royal Marsden Hospital, Downs Road, Sutton, Surrey, United Kingdom
| | - Carla Abreu
- Department of Nuclear Medicine, Royal Marsden Hospital, Downs Road, Sutton, Surrey, SM2 5PT, United Kingdom
| | - Martin Lee
- Department of Physics, Royal Marsden Hospital, Downs Road, Sutton, Surrey, United Kingdom
| | - Ana Ribeiro
- Department of Nuclear Medicine, Royal Marsden Hospital, Downs Road, Sutton, Surrey, SM2 5PT, United Kingdom
| | | | - Sarah Chittenden
- Department of Physics, Royal Marsden Hospital, Downs Road, Sutton, Surrey, United Kingdom
| | - Jim Thurston
- Department of Physics, Royal Marsden Hospital, Downs Road, Sutton, Surrey, United Kingdom
| | - Yong Du
- Department of Nuclear Medicine, Royal Marsden Hospital, Downs Road, Sutton, Surrey, SM2 5PT, United Kingdom
| | - Jonathan Gear
- Department of Physics, Royal Marsden Hospital, Downs Road, Sutton, Surrey, United Kingdom
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Bardiès M, Gear JI. Scientific Developments in Imaging and Dosimetry for Molecular Radiotherapy. Clin Oncol (R Coll Radiol) 2020; 33:117-124. [PMID: 33281018 DOI: 10.1016/j.clon.2020.11.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/12/2020] [Accepted: 11/09/2020] [Indexed: 11/29/2022]
Abstract
Molecular radiotherapy is a rapidly developing field with new vector and isotope combinations continually added to market. As with any radiotherapy treatment, it is vital that the absorbed dose and toxicity profile are adequately characterised. Methodologies for absorbed dose calculations for radiopharmaceuticals were generally developed to characterise stochastic effects and not suited to calculations on a patient-specific basis. There has been substantial scientific and technological development within the field of molecular radiotherapy dosimetry to answer this challenge. The development of imaging systems and advanced processing techniques enable the acquisition of accurate measurements of radioactivity within the body. Activity assessment combined with dosimetric models and radiation transport algorithms make individualised absorbed dose calculations not only feasible, but commonplace in a variety of commercially available software packages. The development of dosimetric parameters beyond the absorbed dose has also allowed the possibility to characterise the effect of irradiation by including biological parameters that account for radiation absorbed dose rates, gradients and spatial and temporal energy distribution heterogeneities. Molecular radiotherapy is in an exciting time of its development and the application of dosimetry in this field can only have a positive influence on its continued progression.
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Affiliation(s)
- M Bardiès
- Centre de Recherches en Cancérologie de Toulouse UMR 1037, Toulouse, France; INSERM UMR 1037 Université Toulouse III Paul Sabatier, Toulouse, France
| | - J I Gear
- Joint Department of Physics, The Royal Marsden NHS Foundation Trust and Institute of Cancer Research, Sutton, Surrey, UK.
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Khalili S, Miri‐Hakimabad H, Hoseinian‐Azghadi E. Patient‐specific anatomical models for radioiodine dosimetry in treatment of hyperthyroidism: is it necessary? Med Phys 2020; 47:5357-5365. [DOI: 10.1002/mp.14454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 07/14/2020] [Accepted: 08/04/2020] [Indexed: 11/11/2022] Open
Affiliation(s)
- Susan Khalili
- Physics Department Faculty of Science Ferdowsi University of Mashhad Mashhad91775‐1436 Iran
| | - Hashem Miri‐Hakimabad
- Physics Department Faculty of Science Ferdowsi University of Mashhad Mashhad91775‐1436 Iran
| | - Elie Hoseinian‐Azghadi
- Physics Department Faculty of Science Ferdowsi University of Mashhad Mashhad91775‐1436 Iran
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12
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Neira S, Guiu‐Souto J, Díaz‐Botana P, Pais P, Fernández C, Pubul V, Ruibal Á, Candela‐Juan C, Gago‐Arias A, Pombar M, Pardo‐Montero J. Quantification of internal dosimetry in PET patients: individualized Monte Carlo vs generic phantom-based calculations. Med Phys 2020; 47:4574-4588. [PMID: 32569389 PMCID: PMC7586975 DOI: 10.1002/mp.14344] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 06/11/2020] [Accepted: 06/12/2020] [Indexed: 12/15/2022] Open
Abstract
PURPOSE The purpose of this work is to calculate individualized dose distributions in patients undergoing 18 F-FDG PET/CT studies through a methodology based on full Monte Carlo (MC) simulations and PET/CT patient images, and to compare such values with those obtained by employing nonindividualized phantom-based methods. METHODS We developed a MC-based methodology for individualized internal dose calculations, which relies on CT images (for organ segmentation and dose deposition), PET images (for organ segmentation and distributions of activities), and a biokinetic model (which works with information provided by PET and CT images) to obtain cumulated activities. The software vGATE version 8.1. was employed to carry out the Monte Carlo calculations. We also calculated deposited doses with nonindividualized phantom-based methods (Cristy-Eckerman, Stabin, and ICRP-133). RESULTS Median MC-calculated dose/activity values are within 0.01-0.03 mGy/MBq for most organs, with higher doses delivered especially to the bladder wall, major vessels, and brain (medians of 0.058, 0.060, 0.066 mGy/MBq, respectively). Comparison with values obtained with nonindividualized phantom-based methods has shown important differences in many cases (ranging from -80% to + 260%). These differences are significant (p < 0.05) for several organs/tissues, namely, remaining tissues, adrenals, bladder wall, bones, upper large intestine, heart, pancreas, skin, and stomach wall. CONCLUSIONS The methodology presented in this work is a viable and useful method to calculate internal dose distributions in patients undergoing medical procedures involving radiopharmaceuticals, individually, with higher accuracy than phantom-based methods, fulfilling the guidelines provided by the European Council directive 2013/59/Euratom.
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Affiliation(s)
- Sara Neira
- Group of Medical Physics and BiomathematicsInstituto de Investigación Sanitaria de SantiagoTravesía Choupana s/nSantiago de Compostela15706Spain
| | - Jacobo Guiu‐Souto
- Department of Medical PhysicsCentro Oncolóxico de GaliciaC/ Doctor Camilo Beiras 1Coruña15009 ASpain
| | - Pablo Díaz‐Botana
- Group of Medical Physics and BiomathematicsInstituto de Investigación Sanitaria de SantiagoTravesía Choupana s/nSantiago de Compostela15706Spain
- Galician Supercomputation Center (CESGA)Avenida de Vigo s/nSantiago de Compostela15705Spain
| | - Paulino Pais
- Department of Nuclear MedicineCentro Oncolóxico de GaliciaC/ Doctor Camilo Beiras 1Coruña15009 ASpain
| | - Carlos Fernández
- Department of Medical PhysicsCentro Oncolóxico de GaliciaC/ Doctor Camilo Beiras 1Coruña15009 ASpain
| | - Virginia Pubul
- Department of Nuclear MedicineComplexo Hospitalario Universitario de Santiago de CompostelaTravesía Choupana s/nSantiago de Compostela15706Spain
| | - Álvaro Ruibal
- Department of Nuclear MedicineComplexo Hospitalario Universitario de Santiago de CompostelaTravesía Choupana s/nSantiago de Compostela15706Spain
- Group of Molecular Imaging and OncologyInstituto de Investigación Sanitaria de Santiago, Travesía Choupana s/nSantiago de Compostela15706Spain
- Molecular Imaging GroupDepartment of RadiologyFaculty of MedicineUniversidade de Santiago de CompostelaCampus VidaSantiago de Compostela15782Spain
- Fundación TejerinaC/ José Abascal 40Madrid28003Spain
| | - Cristian Candela‐Juan
- Centro Nacional de DosimetríaInstituto Nacional de Gestión SanitariaAv. Campanar 21Valencia46009Spain
| | - Araceli Gago‐Arias
- Group of Medical Physics and BiomathematicsInstituto de Investigación Sanitaria de SantiagoTravesía Choupana s/nSantiago de Compostela15706Spain
- Instituto de FísicaPontificia Universidad Católica de ChileSantiagoChile
| | - Miguel Pombar
- Group of Molecular Imaging and OncologyInstituto de Investigación Sanitaria de Santiago, Travesía Choupana s/nSantiago de Compostela15706Spain
- Department of Medical PhysicsComplexo Hospitalario Universitario de Santiago de CompostelaTravesía da Choupana s/nSantiago de Compostela15706Spain
| | - Juan Pardo‐Montero
- Group of Medical Physics and BiomathematicsInstituto de Investigación Sanitaria de SantiagoTravesía Choupana s/nSantiago de Compostela15706Spain
- Department of Medical PhysicsComplexo Hospitalario Universitario de Santiago de CompostelaTravesía da Choupana s/nSantiago de Compostela15706Spain
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13
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Whole-body voxel-based internal dosimetry using deep learning. Eur J Nucl Med Mol Imaging 2020; 48:670-682. [PMID: 32875430 PMCID: PMC8036208 DOI: 10.1007/s00259-020-05013-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 08/23/2020] [Indexed: 12/20/2022]
Abstract
Purpose In the era of precision medicine, patient-specific dose calculation using Monte Carlo (MC) simulations is deemed the gold standard technique for risk-benefit analysis of radiation hazards and correlation with patient outcome. Hence, we propose a novel method to perform whole-body personalized organ-level dosimetry taking into account the heterogeneity of activity distribution, non-uniformity of surrounding medium, and patient-specific anatomy using deep learning algorithms. Methods We extended the voxel-scale MIRD approach from single S-value kernel to specific S-value kernels corresponding to patient-specific anatomy to construct 3D dose maps using hybrid emission/transmission image sets. In this context, we employed a Deep Neural Network (DNN) to predict the distribution of deposited energy, representing specific S-values, from a single source in the center of a 3D kernel composed of human body geometry. The training dataset consists of density maps obtained from CT images and the reference voxelwise S-values generated using Monte Carlo simulations. Accordingly, specific S-value kernels are inferred from the trained model and whole-body dose maps constructed in a manner analogous to the voxel-based MIRD formalism, i.e., convolving specific voxel S-values with the activity map. The dose map predicted using the DNN was compared with the reference generated using MC simulations and two MIRD-based methods, including Single and Multiple S-Values (SSV and MSV) and Olinda/EXM software package. Results The predicted specific voxel S-value kernels exhibited good agreement with the MC-based kernels serving as reference with a mean relative absolute error (MRAE) of 4.5 ± 1.8 (%). Bland and Altman analysis showed the lowest dose bias (2.6%) and smallest variance (CI: − 6.6, + 1.3) for DNN. The MRAE of estimated absorbed dose between DNN, MSV, and SSV with respect to the MC simulation reference were 2.6%, 3%, and 49%, respectively. In organ-level dosimetry, the MRAE between the proposed method and MSV, SSV, and Olinda/EXM were 5.1%, 21.8%, and 23.5%, respectively. Conclusion The proposed DNN-based WB internal dosimetry exhibited comparable performance to the direct Monte Carlo approach while overcoming the limitations of conventional dosimetry techniques in nuclear medicine.
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14
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Chauvin M, Borys D, Botta F, Bzowski P, Dabin J, Denis-Bacelar AM, Desbrée A, Falzone N, Lee BQ, Mairani A, Malaroda A, Mathieu G, McKay E, Mora-Ramirez E, Robinson AP, Sarrut D, Struelens L, Gil AV, Bardiès M. OpenDose: Open-Access Resource for Nuclear Medicine Dosimetry. J Nucl Med 2020; 61:1514-1519. [PMID: 32169912 DOI: 10.2967/jnumed.119.240366] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 02/26/2020] [Indexed: 11/16/2022] Open
Abstract
Radiopharmaceutical dosimetry depends on the localization in space and time of radioactive sources and requires the estimation of the amount of energy emitted by the sources deposited within targets. In particular, when computing resources are not accessible, this task can be performed using precomputed tables of specific absorbed fractions (SAFs) or S values based on dosimetric models. The aim of the OpenDose collaboration is to generate and make freely available a range of dosimetric data and tools. Methods: OpenDose brings together resources and expertise from 18 international teams to produce and compare traceable dosimetric data using 6 of the most popular Monte Carlo codes in radiation transport (EGSnrc/EGS++, FLUKA, GATE, Geant4, MCNP/MCNPX, and PENELOPE). SAFs are uploaded, together with their associated statistical uncertainties, in a relational database. S values are then calculated from monoenergetic SAFs on the basis of the radioisotope decay data presented in International Commission on Radiological Protection Publication 107. Results: The OpenDose collaboration produced SAFs for all source region and target combinations of the 2 International Commission on Radiological Protection Publication 110 adult reference models. SAFs computed from the different Monte Carlo codes were in good agreement at all energies, with SDs below individual statistical uncertainties. Calculated S values were in good agreement with OLINDA/EXM 2.0 (commercial) and IDAC-Dose 2.1 (free) software. A dedicated website (www.opendose.org) has been developed to provide easy and open access to all data. Conclusion: The OpenDose website allows the display and downloading of SAFs and the corresponding S values for 1,252 radionuclides. The OpenDose collaboration, open to new research teams, will extend data production to other dosimetric models and implement new free features, such as online dosimetric tools and patient-specific absorbed dose calculation software, together with educational resources.
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Affiliation(s)
- Maxime Chauvin
- CRCT, UMR 1037, Inserm, Université Toulouse III Paul Sabatier, Toulouse, France
| | - Damian Borys
- Department of Systems Biology and Engineering, Silesian University of Technology, Gliwice, Poland
| | - Francesca Botta
- Medical Physics Unit, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Pawel Bzowski
- Department of Systems Biology and Engineering, Silesian University of Technology, Gliwice, Poland
| | - Jérémie Dabin
- SCK-CEN, Belgian Nuclear Research Centre, Mol, Belgium
| | | | - Aurélie Desbrée
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay-aux-Roses, France
| | - Nadia Falzone
- MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United, Kingdom.,GenesisCare, Sydney, New South Wales, Australia
| | - Boon Quan Lee
- MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United, Kingdom.,GenesisCare, Sydney, New South Wales, Australia
| | - Andrea Mairani
- Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany.,Medical Physics, National Centre of Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - Alessandra Malaroda
- School of Physics and CMRP, University of Wollongong, Wollongong, New South Wales, Australia.,Theranostic and Nuclear Medicine Department, St. Vincent's Public Hospital, Sydney, New South Wales, Australia
| | - Gilles Mathieu
- Département du Système d'Information, Inserm, Paris, France
| | - Erin McKay
- St. George Hospital, Sydney, New South Wales, Australia
| | - Erick Mora-Ramirez
- CRCT, UMR 1037, Inserm, Université Toulouse III Paul Sabatier, Toulouse, France.,CICANUM, Escuela de Física, Universidad de Costa Rica, San Jose, Costa Rica
| | - Andrew P Robinson
- National Physical Laboratory, Teddington, United Kingdom.,Schuster Laboratory, School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom; and.,The Christie NHS Foundation Trust, Manchester, United Kingdom
| | | | | | - Alex Vergara Gil
- CRCT, UMR 1037, Inserm, Université Toulouse III Paul Sabatier, Toulouse, France
| | - Manuel Bardiès
- CRCT, UMR 1037, Inserm, Université Toulouse III Paul Sabatier, Toulouse, France
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15
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Gear J, Chiesa C, Lassmann M, Gabiña PM, Tran-Gia J, Stokke C, Flux G. EANM Dosimetry Committee series on standard operational procedures for internal dosimetry for 131I mIBG treatment of neuroendocrine tumours. EJNMMI Phys 2020; 7:15. [PMID: 32144574 PMCID: PMC7060302 DOI: 10.1186/s40658-020-0282-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 02/13/2020] [Indexed: 11/23/2022] Open
Abstract
The purpose of the EANM Dosimetry Committee Series on "Standard Operational Procedures for Dosimetry" (SOP) is to provide advice to scientists and clinicians on how to perform patient-specific absorbed dose assessments. This SOP describes image and data acquisition parameters and dosimetry calculations to determine the absorbed doses delivered to whole-body, tumour and normal organs following a therapeutic administration of 131I mIBG for the treatment of neuroblastoma or adult neuroendocrine tumours. Recommendations are based on evidence in recent literature where available and on expert opinion within the community. This SOP is intended to promote standardisation of practice within the community and as such is based on the facilities and expertise that should be available to any centre able to perform specialised treatments with radiopharmaceuticals and patient-specific dosimetry. A clinical example is given to demonstrate the application of the absorbed dose calculations.
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Affiliation(s)
- Jonathan Gear
- Joint Department of Physics, Royal Marsden Hospital & Institute of Cancer Research, Sutton, UK.
| | - Carlo Chiesa
- Nuclear Medicine, Foundation IRCCS Istituto Nazionale Tumori, Milan, Italy
| | - Michael Lassmann
- Department of Nuclear Medicine, University of Würzburg, 97080, Würzburg, Germany
| | - Pablo Mínguez Gabiña
- Department of Medical Physics and Radiation Protection, Gurutzeta/Cruces University Hospital, Barakaldo, Spain
| | - Johannes Tran-Gia
- Department of Nuclear Medicine, University of Würzburg, 97080, Würzburg, Germany
| | - Caroline Stokke
- Department of Diagnostic Physics, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - Glenn Flux
- Joint Department of Physics, Royal Marsden Hospital & Institute of Cancer Research, Sutton, UK
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16
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Factors affecting accuracy of S values and determination of time-integrated activity in clinical Lu-177 dosimetry. Ann Nucl Med 2019; 33:521-531. [DOI: 10.1007/s12149-019-01365-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 04/16/2019] [Indexed: 12/20/2022]
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17
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Marin G, Vanderlinden B, Karfis I, Guiot T, Wimana Z, Reynaert N, Vandenberghe S, Flamen P. A dosimetry procedure for organs-at-risk in 177Lu peptide receptor radionuclide therapy of patients with neuroendocrine tumours. Phys Med 2018; 56:41-49. [PMID: 30527088 DOI: 10.1016/j.ejmp.2018.11.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 10/05/2018] [Accepted: 11/02/2018] [Indexed: 01/25/2023] Open
Abstract
PURPOSE Peptide receptor radionuclide therapy with 177Lu-DOTATATE has become a standard treatment modality in neuroendocrine tumours (NETs). No consensus has yet been reached however regarding the absorbed dose threshold for lesion response, the absorbed dose limit to organs-at-risk, and the optimal fractionation and activity to be administered. This is partly due to a lack of uniform and comparable dosimetry protocols. The present article details the development of an organ-at-risk dosimetry procedure, which could be implemented and used routinely in a clinical context. METHODS Forty-seven patients with NETs underwent 177Lu-DOTATATE therapy. Three SPECT/CT images were acquired at 4, 24 and 144-192 h post-injection. Three blood samples were obtained together with the SPECT/CT acquisitions and 2 additional samples were obtained around 30 min and 1 h post-injection. A bi-exponential fit was used to compute the source organ time-integrated activity coefficients. Coefficients were introduced into OLINDA/EXM software to compute organ-at-risk absorbed doses. Median values for all patients were computed for absorbed dose coefficient D/A0 and for late effective half-life T1/2eff for kidneys, spleen and red marrow. RESULTS Dosimetry resulted in a median[interquartile range] of 0.78[0.35], 1.07[0.58] and 0.028[0.010] Gy/GBq for D/A0 and of 55[9], 71[9] and 52[18] h for T1/2eff for kidneys, spleen and red marrow respectively. CONCLUSIONS A dosimetry procedure for organs-at-risk in 177Lu-DOTATATE therapy based on serial SPECT/CT images and blood samples can be implemented routinely in a clinical context with limited patient burden. The results obtained were in accordance with those of other centres.
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Affiliation(s)
- Gwennaëlle Marin
- Department of Medical Physics, Institut Jules Bordet-Université Libre de Bruxelles (ULB), 121 boulevard de Waterloo, 1000 Brussels, Belgium; Medical Imaging and Signal Processing (MEDISIP), Department of Electronics and Information Systems (ELIS), Faculty of Engineering and Architecture (FEA), Ghent University (UGent), 185 De Pintelaan, 9000 Gent, Belgium.
| | - Bruno Vanderlinden
- Department of Medical Physics, Institut Jules Bordet-Université Libre de Bruxelles (ULB), 121 boulevard de Waterloo, 1000 Brussels, Belgium.
| | - Ioannis Karfis
- Department of Nuclear Medicine, Institut Jules Bordet-Université Libre de Bruxelles (ULB), 121 boulevard de Waterloo, 1000 Brussels, Belgium.
| | - Thomas Guiot
- Department of Medical Physics, Institut Jules Bordet-Université Libre de Bruxelles (ULB), 121 boulevard de Waterloo, 1000 Brussels, Belgium.
| | - Zena Wimana
- Department of Nuclear Medicine, Institut Jules Bordet-Université Libre de Bruxelles (ULB), 121 boulevard de Waterloo, 1000 Brussels, Belgium.
| | - Nick Reynaert
- Department of Medical Physics, Institut Jules Bordet-Université Libre de Bruxelles (ULB), 121 boulevard de Waterloo, 1000 Brussels, Belgium.
| | - Stefaan Vandenberghe
- Medical Imaging and Signal Processing (MEDISIP), Department of Electronics and Information Systems (ELIS), Faculty of Engineering and Architecture (FEA), Ghent University (UGent), 185 De Pintelaan, 9000 Gent, Belgium.
| | - Patrick Flamen
- Department of Nuclear Medicine, Institut Jules Bordet-Université Libre de Bruxelles (ULB), 121 boulevard de Waterloo, 1000 Brussels, Belgium.
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18
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Besemer AE, Grudzinski JJ, Weichert JP, Hall LT, Bednarz BP. Pretreatment CLR 124 Positron Emission Tomography Accurately Predicts CLR 131 Three-Dimensional Dosimetry in a Triple-Negative Breast Cancer Patient. Cancer Biother Radiopharm 2018; 34:13-23. [PMID: 30351218 DOI: 10.1089/cbr.2018.2568] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
INTRODUCTION CLR1404 is a theranostic molecular agent that can be radiolabeled with 124I (CLR 124) for positron emission tomography (PET) imaging, or 131I (CLR 131) for single-photon emission computed tomography (SPECT) imaging and targeted radionuclide therapy. This pilot study evaluated a pretreatment dosimetry methodology in a triple-negative breast cancer patient who was uniquely enrolled in both a CLR 124 PET imaging clinical trial and a CLR 131 therapeutic dose escalation clinical trial. MATERIALS AND METHODS Three-dimensional PET/CT images were acquired at 1, 3, 24, 48, and 120 h postinjection of 178 MBq CLR 124. One month later, pretherapy 2D whole-body planar images were acquired at 0.25, 5, 24, 48, and 144 h postinjection of 370 MBq CLR 131. Following the therapeutic administration of 1990 MBq CLR 131, 3D SPECT/CT images were acquired at 74, 147, 334, and 505 h postinjection. The therapeutic CLR 131 voxel-level absorbed dose was estimated from PET (RAPID PET) and SPECT (RAPID SPECT) images using a Geant4-based Monte Carlo dosimetry platform called RAPID (Radiopharmaceutical Assessment Platform for Internal Dosimetry), and region of interest (ROI) mean doses were also estimated using the OLINDA/EXM software based on PET (OLINDA PET), SPECT (OLINDA SPECT), and planar (OLINDA planar) images. RESULTS The RAPID PET and OLINDA PET tracer-predicted ROI mean doses correlated well (m ≥ 0.631, R2 ≥ 0.694, p ≤ 0.01) with both the RAPID SPECT and OLINDA SPECT therapeutic mean doses. The 2D planar images did not have any significant correlations. The ROI mean doses differed by -4% to -43% between RAPID and OLINDA/EXM, and by -19% to 29% between PET and SPECT. The 3D dose distributions and dose volume histograms calculated with RAPID were similar for the PET/CT and SPECT/CT. CONCLUSIONS This pilot study demonstrated that CLR 124 pretreatment PET images can be used to predict CLR 131 3D therapeutic dosimetry better than CLR 131 2D planar images. In addition, unlike OLINDA/EXM, Monte Carlo dosimetry methods were capable of accurately predicting dose heterogeneity, which is important for predicting dose-response relationships and clinical outcomes.
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Affiliation(s)
- Abigail E Besemer
- 1 Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin.,2 Department of Human Oncology, University of Wisconsin-Madison, Madison, Wisconsin.,3 Department of Radiation Oncology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Joseph J Grudzinski
- 1 Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Jamey P Weichert
- 1 Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin.,4 Department of Radiology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin.,5 Carbone Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin
| | - Lance T Hall
- 4 Department of Radiology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin.,5 Carbone Cancer Center, University of Wisconsin-Madison, Madison, Wisconsin
| | - Bryan P Bednarz
- 1 Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin
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19
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Wang H, Sun X, Wu T, Li C, Chen Z, Liao M, Li M, Yan W, Huang H, Yang J, Tan Z, Hui L, Liu Y, Pan H, Qu Y, Chen Z, Tan L, Yu L, Shi H, Huo L, Zhang Y, Tang X, Zhang S, Liu C. Deformable torso phantoms of Chinese adults for personalized anatomy modelling. J Anat 2018; 233:121-134. [PMID: 29663370 PMCID: PMC5987821 DOI: 10.1111/joa.12815] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/19/2018] [Indexed: 11/26/2022] Open
Abstract
In recent years, there has been increasing demand for personalized anatomy modelling for medical and industrial applications, such as ergonomics device development, clinical radiological exposure simulation, biomechanics analysis, and 3D animation character design. In this study, we constructed deformable torso phantoms that can be deformed to match the personal anatomy of Chinese male and female adults. The phantoms were created based on a training set of 79 trunk computed tomography (CT) images (41 males and 38 females) from normal Chinese subjects. Major torso organs were segmented from the CT images, and the statistical shape model (SSM) approach was used to learn the inter-subject anatomical variations. To match the personal anatomy, the phantoms were registered to individual body surface scans or medical images using the active shape model method. The constructed SSM demonstrated anatomical variations in body height, fat quantity, respiratory status, organ geometry, male muscle size, and female breast size. The masses of the deformed phantom organs were consistent with Chinese population organ mass ranges. To validate the performance of personal anatomy modelling, the phantoms were registered to the body surface scan and CT images. The registration accuracy measured from 22 test CT images showed a median Dice coefficient over 0.85, a median volume recovery coefficient (RCvlm ) between 0.85 and 1.1, and a median averaged surface distance (ASD) < 1.5 mm. We hope these phantoms can serve as computational tools for personalized anatomy modelling for the research community.
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Affiliation(s)
- Hongkai Wang
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Xiaobang Sun
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
- Department of Information TechnologyUniversity of JyväskyläJyväskyläFinland
| | - Tongning Wu
- China Academy of Industry and Communications TechnologyBeijingChina
| | - Congsheng Li
- China Academy of Industry and Communications TechnologyBeijingChina
| | - Zhonghua Chen
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Meiying Liao
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Mengci Li
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Wen Yan
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Hui Huang
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Jia Yang
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Ziyu Tan
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Libo Hui
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Yue Liu
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Hang Pan
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Yue Qu
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Zhaofeng Chen
- Department of Biomedical EngineeringFaculty of Electronic Information and Electrical EngineeringDalian University of TechnologyDalianLiaoningChina
| | - Liwen Tan
- Institute of Digital MedicineThird Military Medical UniversityChongqingChina
| | - Lijuan Yu
- The Affiliated Cancer Hospital of Hainan Medical CollegeHaikouHainanChina
| | - Hongcheng Shi
- Department of Nuclear MedicineZhongshan HospitalFudan UniversityShanghaiChina
| | - Li Huo
- Department of Nuclear MedicinePeking Union Medical College HospitalBeijingChina
| | - Yanjun Zhang
- Department of Nuclear Medicinethe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoningChina
| | - Xin Tang
- Trauma Department of Orthopaedicsthe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoningChina
| | - Shaoxiang Zhang
- Institute of Digital MedicineThird Military Medical UniversityChongqingChina
| | - Changjian Liu
- Trauma Department of Orthopaedicsthe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoningChina
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20
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Papadimitroulas P, Erwin WD, Iliadou V, Kostou T, Loudos G, Kagadis GC. A personalized, Monte Carlo-based method for internal dosimetric evaluation of radiopharmaceuticals in children. Med Phys 2018; 45:3939-3949. [PMID: 29920693 DOI: 10.1002/mp.13055] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 05/31/2018] [Accepted: 06/12/2018] [Indexed: 11/08/2022] Open
Abstract
PURPOSE Herein, we introduce a methodology for estimating the absorbed dose in organs at risk that is based on specified clinically derived radiopharmaceutical biodistributions and personalized anatomical characteristics. METHODS To evaluate the proposed methodology, we used realistic Monte Carlo (MC) simulations and computational pediatric models to calculate a parameter called in this work the "specific absorbed dose rate" (SADR). The SADR is a unique quantitative metric in that it is specific to a particular organ. It is defined as the absorbed dose rate in an organ when the biodistribution of radioactivity over the whole body is considered. Initially, we applied a validation procedure that calculated specific absorbed fractions (SAFs) from mono-energetic photon sources in the range of 10 keV-2 MeV and compared them with previously published data. We calculated the SADRs for five different radiopharmaceuticals (99m Tc-MDP, 123 I-mIBG, 131 I-MIBG, 131 I-NaI, and 153 Sm-EDTMP) based on their biodistributions at four or five different times; the biodistributions were derived from the clinical scintigraphic data of pediatric patients. We used six models representing male and female patients aged 5, 8, and 14 yr to investigate the absorbed dose variability due to anatomical variations. The GATE Monte Carlo toolkit was used to calculate absorbed doses per organ. Finally, we compared the SADR methodology to that of OLINDA/EXM 1.1 using rescaled masses according to the studied models. Four target organs were considered for calculating the absorbed doses. RESULTS The ratios of SAFs calculated with GATE simulations to those based on previously published data were between 0.9 and 2.2 when the liver was used as a source organ. Subsequently, we used GATE to calculate a dataset of SADRs for the six pediatric models. The SADRs for pediatric models whose total body weights ranged from 20 to 40 kg varied up to approximately 90%, whereas those for models of similar body masses varied less than 15%. Finally, we found absorbed dose discrepancies of approximately 10-150% between the SADR methodology and OLINDA for two different radiopharmaceuticals. Absorbed doses from SADRs and from individualized S-values in the same pediatric model differed approximately 1-50%. CONCLUSIONS Because pediatric radiopharmaceutical dosimetric estimates demonstrate large variation due to the patient's anatomical characteristics, personalized data should be considered. Using our SADR method in a larger population of phantoms and for a variety of radiopharmaceuticals could enhance the personalization of dosimetry in pediatric nuclear medicine. The proposed methodology provides the advantage of creating time-dependent organ dose rate curves.
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Affiliation(s)
| | - William D Erwin
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Vasiliki Iliadou
- Department of Medical Physics, School of Medicine, University of Patras, Rion, GR-26504, Greece
| | - Theodora Kostou
- R&D Department, BET Solutions, 116 Alexandras Ave., Athens, GR-11472, Greece
- Department of Medical Physics, School of Medicine, University of Patras, Rion, GR-26504, Greece
| | - George Loudos
- Department of Biomedical Engineering, University of West Attica, 28 Ag. Spyridonos Street, Egaleo, GR-12210, Greece
| | - George C Kagadis
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Department of Medical Physics, School of Medicine, University of Patras, Rion, GR-26504, Greece
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Besemer AE, Yang YM, Grudzinski JJ, Hall LT, Bednarz BP. Development and Validation of RAPID: A Patient-Specific Monte Carlo Three-Dimensional Internal Dosimetry Platform. Cancer Biother Radiopharm 2018; 33:155-165. [PMID: 29694246 DOI: 10.1089/cbr.2018.2451] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This work describes the development and validation of a patient-specific Monte Carlo internal dosimetry platform called RAPID (Radiopharmaceutical Assessment Platform for Internal Dosimetry). RAPID utilizes serial PET/CT or SPECT/CT images to calculate voxelized three-dimensional (3D) internal dose distributions with the Monte Carlo code Geant4. RAPID's dosimetry calculations were benchmarked against previously published S-values and specific absorbed fractions (SAFs) calculated for monoenergetic photon and electron sources within the Zubal phantom and for S-values calculated for a variety of radionuclides within spherical tumor phantoms with sizes ranging from 1 to 1000 g. The majority of the S-values and SAFs calculated in the Zubal Phantom were within 5% of the previously published values with the exception of a few 10 keV photon SAFs that agreed within 10%, and one value within 16%. The S-values calculated in the spherical tumor phantoms agreed within 2% for 177Lu, 131I, 125I, 18F, and 64Cu, within 3.5% for 211At and 213Bi, within 6.5% for 153Sm, 111In, 89Zr, and 223Ra, and within 9% for 90Y, 68Ga, and 124I. In conclusion, RAPID is capable of calculating accurate internal dosimetry at the voxel-level for a wide variety of radionuclides and could be a useful tool for calculating patient-specific 3D dose distributions.
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Affiliation(s)
- Abigail E Besemer
- 1 Department of Medical Physics, Wisconsin Institutes for Medical Research, University of Wisconsin , Madison, Wisconsin.,2 Department of Human Oncology, School of Medicine and Public Health, University of Wisconsin , Madison, Wisconsin
| | - You Ming Yang
- 1 Department of Medical Physics, Wisconsin Institutes for Medical Research, University of Wisconsin , Madison, Wisconsin.,3 Department of Radiation Oncology, University of California - Los Angeles , Los Angeles, California
| | - Joseph J Grudzinski
- 1 Department of Medical Physics, Wisconsin Institutes for Medical Research, University of Wisconsin , Madison, Wisconsin
| | - Lance T Hall
- 4 Department of Radiology, School of Medicine and Public Health, University of Wisconsin , Madison, Wisconsin.,5 Carbone Cancer Center, University of Wisconsin-Madison , Madison, Wisconsin
| | - Bryan P Bednarz
- 1 Department of Medical Physics, Wisconsin Institutes for Medical Research, University of Wisconsin , Madison, Wisconsin
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Abstract
BACKGROUND The kidneys are the dose-limiting organ in lutetium-177 DOTATATE therapy. Therefore, it is advisable to perform critical organ dosimetry focussed on renal dose in treated patients. A key uncertainty in such dose estimates is the use of standard phantoms to represent the individual patient. The primary aim of this study was to investigate the accuracy of methods for estimating kidney size, and hence absorbed kidney dose, by comparison with individual measurements from computed tomography (CT) imaging. MATERIALS AND METHODS Kidney volume was measured using diagnostic CT images for 57 patients who underwent lutetium-177 DOTATATE therapy. Kidney mass was also estimated in two ways: using the standard adult phantoms, as well as through the application of a weight scaling factor to these phantoms and their organs. Dose calculations were performed for each of the three methods using OLINDA/EXM software. RESULTS Scaling of the phantom by patient weight gave a more accurate result when compared with the CT gold standard than the standard phantom. The dose difference from the CT method had mean values of 1.4% (SD=22.6%) and 8.4% (SD=21.5%) for scaled and unscaled, respectively. Patient weight was not found to be a good predictor of kidney mass in these patients (r of 0.12 from linear regression analysis). CONCLUSION The most accurate method of organ volume estimation would be individual measurements from CT imaging; however, where this is not possible, scaling of organ masses by weight ratio is more accurate than the use of the standard phantom.
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Zhu W, Yao S, Xing H, Zhang H, Tai YC, Zhang Y, Liu Y, Ma Y, Wu C, Wang H, Li Z, Wu Z, Zhu Z, Li F, Huo L. Biodistribution and Radiation Dosimetry of the Enterobacteriaceae-Specific Imaging Probe [(18)F]Fluorodeoxysorbitol Determined by PET/CT in Healthy Human Volunteers. Mol Imaging Biol 2017; 18:782-7. [PMID: 27020679 DOI: 10.1007/s11307-016-0946-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
PURPOSE [(18)F]fluorodeoxysorbitol ([(18)F]FDS) is the first radiopharmaceutical specific for a category of bacteria and has the potential to specifically detect Enterobacteriaceae infections. The purpose of this study was to testify the safety and investigate the biodistribution and radiation dosimetry of [(18)F]FDS in healthy human bodies. PROCEDURES Six healthy subjects were intravenously injected with 320-520 MBq [(18)F]FDS. On each subject, 21 whole-body emission scans and a brain scan were conducted at settled time points within the next 4 h. Residence time for each source organ was determined by multi-exponential regression. Absorbed doses for target organs and effective dose were calculated via OLINDA/EXM. RESULTS No adverse events due to [(18)F]FDS injection were observed in the study. The tracer was cleared rapidly from the blood pool through the urinary system. A small portion was cleared into the gut through the hepatobiliary system. The effective dose (ED) was estimated to be 0.021 ± 0.001 mSv/MBq. The organ receiving the highest absorbed dose was the urinary bladder wall (0.25 ± 0.03 mSv/MBq). CONCLUSIONS [(18)F]FDS is safe and well tolerated. The effective dose was comparable to that of other F-18 labeled radiotracers. [(18)F]FDS is suitable for human use from a radiation dosimetry perspective.
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Affiliation(s)
- Wenjia Zhu
- Department of Nuclear Medicine, Peking Union Medical College Hospital, 1# Shuaifuyuan, Dongcheng District, Beijing, China
| | - Shaobo Yao
- Department of Nuclear Medicine, Peking Union Medical College Hospital, 1# Shuaifuyuan, Dongcheng District, Beijing, China
| | - Haiqun Xing
- Department of Nuclear Medicine, Peking Union Medical College Hospital, 1# Shuaifuyuan, Dongcheng District, Beijing, China
| | - Hui Zhang
- Department of Biomedical Engineering, Tsinghua University, Beijing, China
| | - Yuan-Chuan Tai
- Department of Radiology, Washington University in St Louis, St Louis, MI, USA
| | - Yingqiang Zhang
- Department of Nuclear Medicine, Peking Union Medical College Hospital, 1# Shuaifuyuan, Dongcheng District, Beijing, China
| | - Yimin Liu
- Department of Nuclear Medicine, Peking Union Medical College Hospital, 1# Shuaifuyuan, Dongcheng District, Beijing, China
| | - Yanru Ma
- Department of Nuclear Medicine, Peking Union Medical College Hospital, 1# Shuaifuyuan, Dongcheng District, Beijing, China
| | - Chenxi Wu
- Department of Nuclear Medicine, Peking Union Medical College Hospital, 1# Shuaifuyuan, Dongcheng District, Beijing, China
| | - Hongkai Wang
- Department of Biomedical Engineering, Dalian University of technology, Dalian, China
| | - Zibo Li
- Department of Radiology and Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Zhanhong Wu
- Department of Radiology and Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Zhaohui Zhu
- Department of Nuclear Medicine, Peking Union Medical College Hospital, 1# Shuaifuyuan, Dongcheng District, Beijing, China
| | - Fang Li
- Department of Nuclear Medicine, Peking Union Medical College Hospital, 1# Shuaifuyuan, Dongcheng District, Beijing, China
| | - Li Huo
- Department of Nuclear Medicine, Peking Union Medical College Hospital, 1# Shuaifuyuan, Dongcheng District, Beijing, China.
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Xie T, Kuster N, Zaidi H. Computational hybrid anthropometric paediatric phantom library for internal radiation dosimetry. Phys Med Biol 2017; 62:3263-3283. [DOI: 10.1088/1361-6560/aa63d0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Marcatili S, Villoing D, Mauxion T, McParland BJ, Bardiès M. Model-based versus specific dosimetry in diagnostic context: comparison of three dosimetric approaches. Med Phys 2016; 42:1288-96. [PMID: 25735284 DOI: 10.1118/1.4907957] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
PURPOSE The dosimetric assessment of novel radiotracers represents a legal requirement in most countries. While the techniques for the computation of internal absorbed dose in a therapeutic context have made huge progresses in recent years, in a diagnostic scenario the absorbed dose is usually extracted from model-based lookup tables, most often derived from International Commission on Radiological Protection (ICRP) or Medical Internal Radiation Dose (MIRD) Committee models. The level of approximation introduced by these models may impact the resulting dosimetry. The aim of this work is to establish whether a more refined approach to dosimetry can be implemented in nuclear medicine diagnostics, by analyzing a specific case. METHODS The authors calculated absorbed doses to various organs in six healthy volunteers administered with flutemetamol ((18)F) injection. Each patient underwent from 8 to 10 whole body 3D PET/CT scans. This dataset was analyzed using a Monte Carlo (MC) application developed in-house using the toolkit gate that is capable to take into account patient-specific anatomy and radiotracer distribution at the voxel level. They compared the absorbed doses obtained with GATE to those calculated with two commercially available software: OLINDA/EXM and STRATOS implementing a dose voxel kernel convolution approach. RESULTS Absorbed doses calculated with gate were higher than those calculated with OLINDA. The average ratio between gate absorbed doses and OLINDA's was 1.38 ± 0.34 σ (from 0.93 to 2.23). The discrepancy was particularly high for the thyroid, with an average GATE/OLINDA ratio of 1.97 ± 0.83 σ for the six patients. Differences between STRATOS and GATE were found to be higher. The average ratio between GATE and STRATOS absorbed doses was 2.51 ± 1.21 σ (from 1.09 to 6.06). CONCLUSIONS This study demonstrates how the choice of the absorbed dose calculation algorithm may introduce a bias when gamma radiations are of importance, as is the case in nuclear medicine diagnostics.
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Affiliation(s)
- S Marcatili
- Inserm, UMR1037 CRCT, Toulouse F-31000, France and Université Toulouse III-Paul Sabatier, UMR1037 CRCT, Toulouse F-31000, France
| | - D Villoing
- Inserm, UMR1037 CRCT, Toulouse F-31000, France and Université Toulouse III-Paul Sabatier, UMR1037 CRCT, Toulouse F-31000, France
| | - T Mauxion
- Inserm, UMR1037 CRCT, Toulouse F-31000, France and Université Toulouse III-Paul Sabatier, UMR1037 CRCT, Toulouse F-31000, France
| | - B J McParland
- Imaging Technology Group, GE Healthcare, Life Sciences, B22U The Grove Centre, White Lion Road, Amersham, England HP7 9LL, United Kingdom
| | - M Bardiès
- Inserm, UMR1037 CRCT, Toulouse F-31000, France and Université Toulouse III-Paul Sabatier, UMR1037 CRCT, Toulouse F-31000, France
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Momennezhad M, Nasseri S, Zakavi SR, Parach AA, Ghorbani M, Asl RG. A 3D Monte Carlo Method for Estimation of Patient-specific Internal Organs Absorbed Dose for (99m)Tc-hynic-Tyr(3)-octreotide Imaging. World J Nucl Med 2016; 15:114-23. [PMID: 27134562 PMCID: PMC4809152 DOI: 10.4103/1450-1147.174700] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Single-photon emission computed tomography (SPECT)-based tracers are easily available and more widely used than positron emission tomography (PET)-based tracers, and SPECT imaging still remains the most prevalent nuclear medicine imaging modality worldwide. The aim of this study is to implement an image-based Monte Carlo method for patient-specific three-dimensional (3D) absorbed dose calculation in patients after injection of 99mTc-hydrazinonicotinamide (hynic)-Tyr3-octreotide as a SPECT radiotracer. 99mTc patient-specific S values and the absorbed doses were calculated with GATE code for each source-target organ pair in four patients who were imaged for suspected neuroendocrine tumors. Each patient underwent multiple whole-body planar scans as well as SPECT imaging over a period of 1-24 h after intravenous injection of 99mhynic-Tyr3-octreotide. The patient-specific S values calculated by GATE Monte Carlo code and the corresponding S values obtained by MIRDOSE program differed within 4.3% on an average for self-irradiation, and differed within 69.6% on an average for cross-irradiation. However, the agreement between total organ doses calculated by GATE code and MIRDOSE program for all patients was reasonably well (percentage difference was about 4.6% on an average). Normal and tumor absorbed doses calculated with GATE were slightly higher than those calculated with MIRDOSE program. The average ratio of GATE absorbed doses to MIRDOSE was 1.07 ± 0.11 (ranging from 0.94 to 1.36). According to the results, it is proposed that when cross-organ irradiation is dominant, a comprehensive approach such as GATE Monte Carlo dosimetry be used since it provides more reliable dosimetric results.
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Affiliation(s)
- Mehdi Momennezhad
- Department of Medical Physics, Faculty of Medicine, University of Medical Sciences, Mashhad, Iran
| | - Shahrokh Nasseri
- Department of Medical Physics, Medical Physics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Seyed Rasoul Zakavi
- Department of Nuclear Medicine, Nuclear Medicine Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ali Asghar Parach
- Department of Medical Physics, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Mahdi Ghorbani
- Department of Medical Physics, Faculty of Medicine, University of Medical Sciences, Mashhad, Iran
| | - Ruhollah Ghahraman Asl
- Department of Medical Physics, Faculty of Medicine, University of Medical Sciences, Mashhad, Iran
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Grimes J, Celler A. Comparison of internal dose estimates obtained using organ-level, voxel S value, and Monte Carlo techniques. Med Phys 2015; 41:092501. [PMID: 25186410 DOI: 10.1118/1.4892606] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The authors' objective was to compare internal dose estimates obtained using the Organ Level Dose Assessment with Exponential Modeling (OLINDA/EXM) software, the voxel S value technique, and Monte Carlo simulation. Monte Carlo dose estimates were used as the reference standard to assess the impact of patient-specific anatomy on the final dose estimate. METHODS Six patients injected with 99mTc-hydrazinonicotinamide-Tyr3-octreotide were included in this study. A hybrid planar/SPECT imaging protocol was used to estimate 99mTc time-integrated activity coefficients (TIACs) for kidneys, liver, spleen, and tumors. Additionally, TIACs were predicted for 131I, 177Lu, and 90Y assuming the same biological half-lives as the 99mTc labeled tracer. The TIACs were used as input for OLINDA/EXM for organ-level dose calculation and voxel level dosimetry was performed using the voxel S value method and Monte Carlo simulation. Dose estimates for 99mTc, 131I, 177Lu, and 90Y distributions were evaluated by comparing (i) organ-level S values corresponding to each method, (ii) total tumor and organ doses, (iii) differences in right and left kidney doses, and (iv) voxelized dose distributions calculated by Monte Carlo and the voxel S value technique. RESULTS The S values for all investigated radionuclides used by OLINDA/EXM and the corresponding patient-specific S values calculated by Monte Carlo agreed within 2.3% on average for self-irradiation, and differed by as much as 105% for cross-organ irradiation. Total organ doses calculated by OLINDA/EXM and the voxel S value technique agreed with Monte Carlo results within approximately ±7%. Differences between right and left kidney doses determined by Monte Carlo were as high as 73%. Comparison of the Monte Carlo and voxel S value dose distributions showed that each method produced similar dose volume histograms with a minimum dose covering 90% of the volume (D90) agreeing within ±3%, on average. CONCLUSIONS Several aspects of OLINDA/EXM dose calculation were compared with patient-specific dose estimates obtained using Monte Carlo. Differences in patient anatomy led to large differences in cross-organ doses. However, total organ doses were still in good agreement since most of the deposited dose is due to self-irradiation. Comparison of voxelized doses calculated by Monte Carlo and the voxel S value technique showed that the 3D dose distributions produced by the respective methods are nearly identical.
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Affiliation(s)
- Joshua Grimes
- Department of Physics and Astronomy, University of British Columbia, Vancouver V5Z 1L8, Canada
| | - Anna Celler
- Department of Radiology, University of British Columbia, Vancouver V5Z 1L8, Canada
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Grimes J, Uribe C, Celler A. JADA: a graphical user interface for comprehensive internal dose assessment in nuclear medicine. Med Phys 2014; 40:072501. [PMID: 23822450 DOI: 10.1118/1.4810963] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The main objective of this work was to design a comprehensive dosimetry package that would keep all aspects of internal dose calculation within the framework of a single software environment and that would be applicable for a variety of dose calculation approaches. METHODS Our MATLAB-based graphical user interface (GUI) can be used for processing data obtained using pure planar, pure SPECT, or hybrid planar/SPECT imaging. Time-activity data for source regions are obtained using a set of tools that allow the user to reconstruct SPECT images, load images, coregister a series of planar images, and to perform two-dimensional and three-dimensional image segmentation. Curve fits are applied to the acquired time-activity data to construct time-activity curves, which are then integrated to obtain time-integrated activity coefficients. Subsequently, dose estimates are made using one of three methods. RESULTS The organ level dose calculation subGUI calculates mean organ doses that are equivalent to dose assessment performed by OLINDA/EXM. Voxelized dose calculation options, which include the voxel S value approach and Monte Carlo simulation using the EGSnrc user code DOSXYZnrc, are available within the process 3D image data subGUI. CONCLUSIONS The developed internal dosimetry software package provides an assortment of tools for every step in the dose calculation process, eliminating the need for manual data transfer between programs. This saves times and minimizes user errors, while offering a versatility that can be used to efficiently perform patient-specific internal dose calculations in a variety of clinical situations.
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Affiliation(s)
- Joshua Grimes
- Department of Physics and Astronomy, University of British Columbia, Vancouver V5Z 1M9, Canada.
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Mauxion T, Barbet J, Suhard J, Pouget JP, Poirot M, Bardiès M. Improved realism of hybrid mouse models may not be sufficient to generate reference dosimetric data. Med Phys 2013; 40:052501. [DOI: 10.1118/1.4800801] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Glatting G, Bardiès M, Lassmann M. Treatment planning in molecular radiotherapy. Z Med Phys 2013; 23:262-9. [PMID: 23597414 DOI: 10.1016/j.zemedi.2013.03.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 03/05/2013] [Accepted: 03/14/2013] [Indexed: 01/09/2023]
Abstract
In molecular radiotherapy a radionuclide or a radioactively labelled pharmaceutical is administered to the patient. Treatment planning therefore comprises the determination of activity to administer. This administered activity should maximize tumour cell sterilization while minimizing normal tissue damage. In this work we present different approaches that are frequently used for determining the suitable activity. These approaches may be cohort- based as in chemotherapy, or patient-specific using dosimetry based on individual biokinetics. The approaches are different with respect to the input complexity, the corresponding costs and - in consequence - the quality of the therapy. In addition, a general scheme for data collection and analysis is proposed. To develop an effective and safe treatment, elaborate data need to be obtained. The main challenges, however, are collecting these complex data and analyse them properly.
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Affiliation(s)
- Gerhard Glatting
- Medical Radiation Physics/Radiation Protection, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
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Schipper MJ, Koral KF, Avram AM, Kaminski MS, Dewaraja YK. Prediction of therapy tumor-absorbed dose estimates in I-131 radioimmunotherapy using tracer data via a mixed-model fit to time activity. Cancer Biother Radiopharm 2013; 27:403-11. [PMID: 22947086 DOI: 10.1089/cbr.2011.1053] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND For individualized treatment planning in radioimmunotherapy (RIT), correlations must be established between tracer-predicted and therapy-delivered absorbed doses. The focus of this work was to investigate this correlation for tumors. METHODS The study analyzed 57 tumors in 19 follicular lymphoma patients treated with I-131 tositumomab and imaged with SPECT/CT multiple times after tracer and therapy administrations. Instead of the typical least-squares fit to a single tumor's measured time-activity data, estimation was accomplished via a biexponential mixed model in which the curves from multiple subjects were jointly estimated. The tumor-absorbed dose estimates were determined by patient-specific Monte Carlo calculation. RESULTS The mixed model gave realistic tumor time-activity fits that showed the expected uptake and clearance phases even with noisy data or missing time points. Correlation between tracer and therapy tumor-residence times (r=0.98; p<0.0001) and correlation between tracer-predicted and therapy-delivered mean tumor-absorbed doses (r=0.86; p<0.0001) were very high. The predicted and delivered absorbed doses were within ± 25% (or within ± 75 cGy) for 80% of tumors. CONCLUSIONS The mixed-model approach is feasible for fitting tumor time-activity data in RIT treatment planning when individual least-squares fitting is not possible due to inadequate sampling points. The good correlation between predicted and delivered tumor doses demonstrates the potential of using a pretherapy tracer study for tumor dosimetry-based treatment planning in RIT.
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Affiliation(s)
- Matthew J Schipper
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109, USA.
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Dieudonné A, Hobbs RF, Lebtahi R, Maurel F, Baechler S, Wahl RL, Boubaker A, Le Guludec D, Sgouros G, Gardin I. Study of the impact of tissue density heterogeneities on 3-dimensional abdominal dosimetry: comparison between dose kernel convolution and direct Monte Carlo methods. J Nucl Med 2012; 54:236-43. [PMID: 23249540 DOI: 10.2967/jnumed.112.105825] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
UNLABELLED Dose kernel convolution (DK) methods have been proposed to speed up absorbed dose calculations in molecular radionuclide therapy. Our aim was to evaluate the impact of tissue density heterogeneities (TDH) on dosimetry when using a DK method and to propose a simple density-correction method. METHODS This study has been conducted on 3 clinical cases: case 1, non-Hodgkin lymphoma treated with (131)I-tositumomab; case 2, a neuroendocrine tumor treatment simulated with (177)Lu-peptides; and case 3, hepatocellular carcinoma treated with (90)Y-microspheres. Absorbed dose calculations were performed using a direct Monte Carlo approach accounting for TDH (3D-RD), and a DK approach (VoxelDose, or VD). For each individual voxel, the VD absorbed dose, D(VD), calculated assuming uniform density, was corrected for density, giving D(VDd). The average 3D-RD absorbed dose values, D(3DRD), were compared with D(VD) and D(VDd), using the relative difference Δ(VD/3DRD). At the voxel level, density-binned Δ(VD/3DRD) and Δ(VDd/3DRD) were plotted against ρ and fitted with a linear regression. RESULTS The D(VD) calculations showed a good agreement with D(3DRD). Δ(VD/3DRD) was less than 3.5%, except for the tumor of case 1 (5.9%) and the renal cortex of case 2 (5.6%). At the voxel level, the Δ(VD/3DRD) range was 0%-14% for cases 1 and 2, and -3% to 7% for case 3. All 3 cases showed a linear relationship between voxel bin-averaged Δ(VD/3DRD) and density, ρ: case 1 (Δ = -0.56ρ + 0.62, R(2) = 0.93), case 2 (Δ = -0.91ρ + 0.96, R(2) = 0.99), and case 3 (Δ = -0.69ρ + 0.72, R(2) = 0.91). The density correction improved the agreement of the DK method with the Monte Carlo approach (Δ(VDd/3DRD) < 1.1%), but with a lesser extent for the tumor of case 1 (3.1%). At the voxel level, the Δ(VDd/3DRD) range decreased for the 3 clinical cases (case 1, -1% to 4%; case 2, -0.5% to 1.5%, and -1.5% to 2%). No more linear regression existed for cases 2 and 3, contrary to case 1 (Δ = 0.41ρ - 0.38, R(2) = 0.88) although the slope in case 1 was less pronounced. CONCLUSION This study shows a small influence of TDH in the abdominal region for 3 representative clinical cases. A simple density-correction method was proposed and improved the comparison in the absorbed dose calculations when using our voxel S value implementation.
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Affiliation(s)
- Arnaud Dieudonné
- Department of Nuclear Medicine, Beaujon Hospital, Assistance Publique-Hôpitaux de Paris APHP, Clichy, France.
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Tomasi G, Turkheimer F, Aboagye E. Importance of quantification for the analysis of PET data in oncology: review of current methods and trends for the future. Mol Imaging Biol 2012; 14:131-46. [PMID: 21842339 DOI: 10.1007/s11307-011-0514-2] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In oncology, positron emission tomography (PET) is an important tool for tumour diagnosis and staging, assessment of response to treatment and evaluation of the pharmacokinetic properties and efficacy of new drugs. Despite its quantitative potential, however, in daily clinical practice PET is used almost exclusively with 2-deoxy-2-[(18)F]fluoro-D-glucose ([(18)F]FDG) and, in addition, [(18)F]FDG data are normally assessed visually or using simple indices as the standardised uptake value (SUV). After explaining why more sophisticated quantification methods can be useful in oncology, the paper reviews the approaches that are commonly used and those available but not routinely employed. Particular emphasis is addressed to the SUV, for its importance in clinical practice. Issues specific to PET quantification in oncology and related examples are then discussed. Finally, some ideas for the development of new quantitative methods for analysing PET data in oncology and for the application of approaches already existing but not commonly employed are presented.
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Affiliation(s)
- Giampaolo Tomasi
- Comprehensive Cancer Imaging Center, Imperial College, Hammersmith Hospital London, London W120NN, UK
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35
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Wierts R, de Pont CD, Brans B, Mottaghy FM, Kemerink GJ. Dosimetry in molecular nuclear therapy. Methods 2011; 55:196-202. [DOI: 10.1016/j.ymeth.2011.09.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 09/11/2011] [Accepted: 09/13/2011] [Indexed: 01/06/2023] Open
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Howard DM, Kearfott KJ, Wilderman SJ, Dewaraja YK. Comparison of I-131 radioimmunotherapy tumor dosimetry: unit density sphere model versus patient-specific Monte Carlo calculations. Cancer Biother Radiopharm 2011; 26:615-21. [PMID: 21939358 DOI: 10.1089/cbr.2011.0965] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
High computational requirements restrict the use of Monte Carlo algorithms for dose estimation in a clinical setting, despite the fact that they are considered more accurate than traditional methods. The goal of this study was to compare mean tumor absorbed dose estimates using the unit density sphere model incorporated in OLINDA with previously reported dose estimates from Monte Carlo simulations using the dose planning method (DPMMC) particle transport algorithm. The dataset (57 tumors, 19 lymphoma patients who underwent SPECT/CT imaging during I-131 radioimmunotherapy) included tumors of varying size, shape, and contrast. OLINDA calculations were first carried out using the baseline tumor volume and residence time from SPECT/CT imaging during 6 days post-tracer and 8 days post-therapy. Next, the OLINDA calculation was split over multiple time periods and summed to get the total dose, which accounted for the changes in tumor size. Results from the second calculation were compared with results determined by coupling SPECT/CT images with DPM Monte Carlo algorithms. Results from the OLINDA calculation accounting for changes in tumor size were almost always higher (median 22%, range -1%-68%) than the results from OLINDA using the baseline tumor volume because of tumor shrinkage. There was good agreement (median -5%, range -13%-2%) between the OLINDA results and the self-dose component from Monte Carlo calculations, indicating that tumor shape effects are a minor source of error when using the sphere model. However, because the sphere model ignores cross-irradiation, the OLINDA calculation significantly underestimated (median 14%, range 2%-31%) the total tumor absorbed dose compared with Monte Carlo. These results show that when the quantity of interest is the mean tumor absorbed dose, the unit density sphere model is a practical alternative to Monte Carlo for some applications. For applications requiring higher accuracy, computer-intensive Monte Carlo calculation is needed.
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Affiliation(s)
- David M Howard
- Department of Nuclear Engineering, University of Michigan, Ann Arbor, MI 48209, USA
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37
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Cassola VF, Milian FM, Kramer R, de Oliveira Lira CAB, Khoury HJ. Standing adult human phantoms based on 10th, 50th and 90th mass and height percentiles of male and female Caucasian populations. Phys Med Biol 2011; 56:3749-72. [PMID: 21628776 DOI: 10.1088/0031-9155/56/13/002] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Computational anthropomorphic human phantoms are useful tools developed for the calculation of absorbed or equivalent dose to radiosensitive organs and tissues of the human body. The problem is, however, that, strictly speaking, the results can be applied only to a person who has the same anatomy as the phantom, while for a person with different body mass and/or standing height the data could be wrong. In order to improve this situation for many areas in radiological protection, this study developed 18 anthropometric standing adult human phantoms, nine models per gender, as a function of the 10th, 50th and 90th mass and height percentiles of Caucasian populations. The anthropometric target parameters for body mass, standing height and other body measures were extracted from PeopleSize, a well-known software package used in the area of ergonomics. The phantoms were developed based on the assumption of a constant body-mass index for a given mass percentile and for different heights. For a given height, increase or decrease of body mass was considered to reflect mainly the change of subcutaneous adipose tissue mass, i.e. that organ masses were not changed. Organ mass scaling as a function of height was based on information extracted from autopsy data. The methods used here were compared with those used in other studies, anatomically as well as dosimetrically. For external exposure, the results show that equivalent dose decreases with increasing body mass for organs and tissues located below the subcutaneous adipose tissue layer, such as liver, colon, stomach, etc, while for organs located at the surface, such as breasts, testes and skin, the equivalent dose increases or remains constant with increasing body mass due to weak attenuation and more scatter radiation caused by the increasing adipose tissue mass. Changes of standing height have little influence on the equivalent dose to organs and tissues from external exposure. Specific absorbed fractions (SAFs) have also been calculated with the 18 anthropometric phantoms. The results show that SAFs decrease with increasing height and increase with increasing body mass. The calculated data suggest that changes of the body mass may have a significant effect on equivalent doses, primarily for external exposure to organs and tissue located below the adipose tissue layer, while for superficial organs, for changes of height and for internal exposures the effects on equivalent dose are small to moderate.
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Affiliation(s)
- V F Cassola
- Department of Nuclear Energy, Federal University of Pernambuco, Avenida Professor Luiz Freire, 1000, CEP 50740-540, Recife, PE, Brazil
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Lassmann M, Strigari L, Bardiès M. Dosimetry is Alive and Well. Cancer Biother Radiopharm 2010; 25:593-5. [DOI: 10.1089/cbr.2010.0874] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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39
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Lassmann M, Chiesa C, Flux G, Bardiès M. EANM Dosimetry Committee guidance document: good practice of clinical dosimetry reporting. Eur J Nucl Med Mol Imaging 2010; 38:192-200. [DOI: 10.1007/s00259-010-1549-3] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Accepted: 07/04/2010] [Indexed: 10/19/2022]
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EANM Dosimetry Committee guidelines for bone marrow and whole-body dosimetry. Eur J Nucl Med Mol Imaging 2010; 37:1238-50. [DOI: 10.1007/s00259-010-1422-4] [Citation(s) in RCA: 171] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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