1
|
Brosch-Lenz J, Kurkowska S, Frey E, Dewaraja YK, Sunderland J, Uribe C. An International Study of Factors Affecting Variability of Dosimetry Calculations, Part 3: Contribution from Calculating Absorbed Dose from Time-Integrated Activity. J Nucl Med 2024; 65:1166-1172. [PMID: 38960715 PMCID: PMC11294060 DOI: 10.2967/jnumed.123.267293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 05/21/2024] [Indexed: 07/05/2024] Open
Abstract
Image-based dosimetry-guided radiopharmaceutical therapy has the potential to personalize treatment by limiting toxicity to organs at risk and maximizing the therapeutic effect. The 177Lu dosimetry challenge of the Society of Nuclear Medicine and Molecular Imaging consisted of 5 tasks assessing the variability in the dosimetry workflow. The fifth task investigated the variability associated with the last step, dose conversion, of the dosimetry workflow on which this study is based. Methods: Reference variability was assessed by 2 medical physicists using different software, methods, and all possible combinations of input segmentation formats and time points as provided in the challenge. General descriptive statistics for absorbed dose values from the global submissions from participants were calculated, and variability was measured using the quartile coefficient of dispersion. Results: For the liver, which included lesions with high uptake, variabilities of up to 36% were found. The baseline analysis showed a variability of 29% in absorbed dose results for the liver from datasets where lesions included and excluded were grouped, indicating that variation in how lesions in normal liver were treated was a significant source of variability. For other organs and lesions, variability was within 7%, independently of software used except for the local deposition method. Conclusion: The choice of dosimetry method or software had a small contribution to the overall variability of dose estimates.
Collapse
Affiliation(s)
- Julia Brosch-Lenz
- Department of Nuclear Medicine, Rechts der Isar Medical Center, Technical University of Munich, Munich, Germany
| | - Sara Kurkowska
- Department of Nuclear Medicine, Pomeranian Medical University, Szczecin, Poland
- Department of Integrative Oncology, BC Cancer Research Institute, Vancouver, British Columbia, Canada
| | - Eric Frey
- Rapid, LLC, Baltimore, Maryland
- Department of Radiology, Johns Hopkins University, Baltimore, Maryland
| | - Yuni K Dewaraja
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - John Sunderland
- Department of Radiology, University of Iowa, Iowa City, Iowa
| | - Carlos Uribe
- Department of Integrative Oncology, BC Cancer Research Institute, Vancouver, British Columbia, Canada;
- Molecular Imaging and Therapy, BC Cancer, Vancouver, British Columbia, Canada; and
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
2
|
Kim KM, Suh M, Cheon GJ, Lee MS, Lee JS. Simplified image-based dosimetry using planar images and patient-specific S-values. Med Phys 2024; 51:5708-5721. [PMID: 38340367 DOI: 10.1002/mp.16974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 01/23/2024] [Accepted: 01/24/2024] [Indexed: 02/12/2024] Open
Abstract
BACKGROUND Single time point measurement approach and hybrid dosimetry were proposed to simplify the dosimetry process. It is anticipated that utilizing patient-specific S-value would enable more accurate dosimetry assessment based on imaging compared to using the conventional MIRD S-values. PURPOSE We performed planar image-based dosimetry scaled with a single SPECT image for the entire treatment cycle using patient-specific S-values (PSS dosimetry) of organs. PSS dosimetry could further simplify the dosimetry procedure compared with a conventional 2D planar/3D SPECT hybrid dosimetry, as PSS dosimetry requires only one SPECT/CT image for the treatment of the entire cycle, whereas the conventional hybrid dosimetry requires a SPECT/CT image for each treatment cycle. METHODS 177Lu-DOTATATE SPECT/CT and planar image datasets acquired from Seoul National University Hospital (SNUH, Seoul, Republic of Korea) were utilized for the evaluation. Images were acquired 4, 24, 48, and 120 h after patients' intravenous injection of 177Lu-DOTATATE. Dose estimations based on a Monte Carlo (MC) simulation using the Geant4 Application for Emission Tomography (GATE) (v.8.2) were considered as the reference. Planar image-based dosimetry scaled with a single SPECT image was performed using the patient-specific S-value (PSS). Briefly, the CT image was considered as the patient's anatomical reference and PSSs were quantified using the multiple voxel S-value (VSV) method. Then, PSS dosimetry was performed by obtaining activity information from sequential planar images and a scaling factor derived from a single SPECT/planar image pair. Hybrid dosimetry using sequential planar images and a single SPECT image was performed for comparison. The absorbed doses of the kidneys, bone marrow (BM) in the lumbar spine, liver, and spleen calculated using the PSS and hybrid dosimetries were compared with the reference MC results. RESULTS The mean differences (MDs) of the self-absorption S-values between S-value of OLINDA/EXM and PSS for the kidneys, liver, and spleen were -0.04%, -2.39%, and -2.62%, respectively. However, the differences in the self-absorption S-values were significantly higher for the BM (84.99%) and the remainder of the body (ROB) (280.84%). The absorbed doses estimated by the PSS and hybrid dosimetries showed relatively high errors compared with MC simulation result, regardless of the organ. In contrast, the PSS and hybrid dosimetries produced similar dose estimates. For the entire cycles of the treatment, the MDs of absorbed doses between PSS and hybrid dosimetries were -3.31%, -6.04%, 3.37%, and -2.17% for the kidneys, BM, liver, and spleen, respectively. Through a correlation analysis and the Wilcoxon signed-rank test, we concluded that there was no significant difference between the results obtained by the two dosimetry methods. CONCLUSIONS As the PSS was derived using CT images with actual anatomical information and organ-specific volume of interest (VOI), PSS dosimetry provided reliable results. PSS dosimetry was robust in estimating the absorbed dose for the later treatment cycles. Therefore, PSS dosimetry outperformed hybrid dosimetry in terms of dose estimation for a greater number of treatment cycles.
Collapse
Affiliation(s)
- Keon Min Kim
- Interdisciplinary Program in Bioengineering, Seoul National University Graduate School, Seoul, South Korea
- Integrated Major in Innovative Medical Science, Seoul National University Graduate School, Seoul, South Korea
| | - Minseok Suh
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, South Korea
- Institute of Radiation Medicine, Medical Research Center, Seoul National University, Seoul, South Korea
| | - Gi Jeong Cheon
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, South Korea
- Institute of Radiation Medicine, Medical Research Center, Seoul National University, Seoul, South Korea
| | - Min Sun Lee
- Korea Atomic Energy Research Institute, Daejeon, South Korea
| | - Jae Sung Lee
- Interdisciplinary Program in Bioengineering, Seoul National University Graduate School, Seoul, South Korea
- Integrated Major in Innovative Medical Science, Seoul National University Graduate School, Seoul, South Korea
- Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, South Korea
- Institute of Radiation Medicine, Medical Research Center, Seoul National University, Seoul, South Korea
| |
Collapse
|
3
|
De Benetti F, Brosch-Lenz J, Guerra González JM, Uribe C, Eiber M, Navab N, Wendler T. DosePatch: physics-inspired cropping layout for patch-based Monte Carlo simulations to provide fast and accurate internal dosimetry. EJNMMI Phys 2024; 11:51. [PMID: 38922372 PMCID: PMC11208390 DOI: 10.1186/s40658-024-00646-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 05/08/2024] [Indexed: 06/27/2024] Open
Abstract
BACKGROUND Dosimetry-based personalized therapy was shown to have clinical benefits e.g. in liver selective internal radiation therapy (SIRT). Yet, there is no consensus about its introduction into clinical practice, mainly as Monte Carlo simulations (gold standard for dosimetry) involve massive computation time. We addressed the problem of computation time and tested a patch-based approach for Monte Carlo simulations for internal dosimetry to improve parallelization. We introduce a physics-inspired cropping layout for patch-based MC dosimetry, and compare it to cropping layouts of the literature as well as dosimetry using organ-S-values, and dose kernels, taking whole-body Monte Carlo simulations as ground truth. This was evaluated in five patients receiving Yttrium-90 liver SIRT. RESULTS The patch-based Monte Carlo approach yielded the closest results to the ground truth, making it a valid alternative to the conventional approach. Our physics-inspired cropping layout and mosaicking scheme yielded a voxel-wise error of < 2% compared to whole-body Monte Carlo in soft tissue, while requiring only ≈ 10% of the time. CONCLUSIONS This work demonstrates the feasibility and accuracy of physics-inspired cropping layouts for patch-based Monte Carlo simulations.
Collapse
Affiliation(s)
- Francesca De Benetti
- Chair for Computer Aided Medical Procedures and Augmented Reality, Technical University of Munich, Garching, Germany
| | - Julia Brosch-Lenz
- Department of Nuclear Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - Jorge Mario Guerra González
- Chair for Computer Aided Medical Procedures and Augmented Reality, Technical University of Munich, Garching, Germany
| | - Carlos Uribe
- Department of Integrative Oncology, BC Cancer Research Institute, Vancouver, Canada
| | - Matthias Eiber
- Department of Nuclear Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - Nassir Navab
- Chair for Computer Aided Medical Procedures and Augmented Reality, Technical University of Munich, Garching, Germany
| | - Thomas Wendler
- Chair for Computer Aided Medical Procedures and Augmented Reality, Technical University of Munich, Garching, Germany.
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany.
- Institute of Digital Medicine, University Hospital Augsburg, Neusaess, Germany.
- Clinical Computational Medical Imaging Research, University of Augsburg, Augsburg, Germany.
| |
Collapse
|
4
|
Morphis M, van Staden JA, du Raan H, Ljungberg M, Sjögreen Gleisner K. Accuracy of patient-specific I-131 dosimetry using hybrid whole-body planar-SPECT/CT I-123 and I-131 imaging. EJNMMI Phys 2024; 11:50. [PMID: 38898326 PMCID: PMC11187057 DOI: 10.1186/s40658-024-00657-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 06/07/2024] [Indexed: 06/21/2024] Open
Abstract
PURPOSE This study aimed to assess the accuracy of patient-specific absorbed dose calculations for tumours and organs at risk in radiopharmaceutical therapy planning, utilizing hybrid planar-SPECT/CT imaging. METHODS Three Monte Carlo (MC) simulated digital patient phantoms were created, with time-activity data for mIBG labelled to I-123 (LEHR and ME collimators) and I-131 (HE collimator). The study assessed the accuracy of the mean absorbed doses for I-131-mIBG therapy treatment planning. Multiple planar whole-body (WB) images were simulated (between 1 to 72 h post-injection (p.i)). The geometric-mean image of the anterior and posterior WB images was calculated, with scatter and attenuation corrections applied. Time-activity curves were created for regions of interest over the liver and two tumours (diameters: 3.0 cm and 5.0 cm) in the WB images. A corresponding SPECT study was simulated at 24 h p.i and reconstructed using the OS-EM algorithm, incorporating scatter, attenuation, collimator-detector response, septal scatter and penetration corrections. MC voxel-based absorbed dose rate calculations used two image sets, (i) the activity distribution represented by the SPECT images and (ii) the activity distribution from the SPECT images distributed uniformly within the volume of interest. Mean absorbed doses were calculated considering photon and charged particle emissions, and beta emissions only. True absorbed doses were calculated by MC voxel-based dosimetry of the known activity distributions for reference. RESULTS Considering photon and charged particle emissions, mean absorbed dose accuracies across all three radionuclide-collimator combinations of 3.8 ± 5.5% and 0.1 ± 0.9% (liver), 5.2 ± 10.0% and 4.3 ± 1.7% (3.0 cm tumour) and 15.0 ± 5.8% and 2.6 ± 0.6% (5.0 cm tumour) were obtained for image set (i) and (ii) respectively. Considering charged particle emissions, accuracies of 2.7 ± 4.1% and 5.7 ± 0.7% (liver), 3.2 ± 10.2% and 9.1 ± 1.7% (3.0 cm tumour) and 13.6 ± 5.7% and 7.0 ± 0.6% (5.0 cm tumour) were obtained for image set (i) and (ii) respectively. CONCLUSION The hybrid WB planar-SPECT/CT method proved accurate for I-131-mIBG dosimetry, suggesting its potential for personalized treatment planning.
Collapse
Affiliation(s)
- Michaella Morphis
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa.
| | - Johan A van Staden
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Hanlie du Raan
- Department of Medical Physics, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | | | | |
Collapse
|
5
|
Gustafsson J, Ljungberg M, Alm Carlsson G, Larsson E, Warfvinge CF, Asp P, Sjögreen Gleisner K. Averaging of absorbed doses: How matter matters. Med Phys 2023; 50:6600-6613. [PMID: 37272586 DOI: 10.1002/mp.16528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 04/05/2023] [Accepted: 05/10/2023] [Indexed: 06/06/2023] Open
Abstract
BACKGROUND Dosimetry in radionuclide therapy often requires the calculation of average absorbed doses within and between spatial regions, for example, for voxel-based dosimetry methods, for paired organs, or across multiple tumors. Formation of such averages can be made in different ways, starting from different definitions. PURPOSE The aim of this study is to formally specify different averaging strategies for absorbed doses, and to compare their results when applied to absorbed dose distributions that are non-uniform within and between regions. METHODS For averaging within regions, two definitions of the average absorbed dose are considered: the simple average over the region (the region average) and the average when weighting by the mass density (density-weighted region average). The latter is shown to follow from the definition of mean absorbed dose according to the ICRU, and to be consistent with the MIRD formalism. For averaging between different spatial regions, three definitions follow: the volume-weighted, the mass-weighted, and the unweighted average. With respect to characterizing non-uniformity, the different average definitions lead to the use of dose-volume histograms (DVHs) (region average), dose-mass histograms (DMHs) (density-weighted region average), and unweighted histograms (unweighted average). Average absorbed doses are calculated for three worked examples, starting from the different definitions. The first, schematic, example concerns the calculation of the average absorbed dose between two regions with different volumes or mass densities. The second, stylized, example concerns voxel-based dosimetry, for which the average absorbed-dose rate within a region is calculated. The geometries studied include three 177 Lu-filled voxelized spheres, where the sphere masses are held constant while the material compositions, densities, and volumes are varied. For comparison, the mean absorbed-dose rates obtained using unit-density sphere S-values are also included. The third example concerns SPECT/CT-based tumor dosimetry for five patients undergoing therapy with 177 Lu-PSMA and six patients undergoing therapy with 177 Lu-DOTA-TATE, for which the average absorbed-dose rates across multiple tumors are calculated. For the second and third examples, analyses also include representations by histograms. RESULTS Example 1 shows that the average absorbed doses, calculated using different definitions, can differ considerably if the masses and absorbed doses for two regions are markedly different. From example 2 it is seen that the density-weighted region average is stable under different activity and density distributions and is also in line with results using S-values. In contrast, the region average varies as function of the activity distribution. In example 3, the absorbed dose rates for individual tumors differ by (1.1 ± 4.3)% and (-0.1 ± 0.4)% with maximum deviations of +34.4% and -1.4% for 177 Lu-PSMA and 177 Lu-DOTA-TATE, respectively, when calculated as region averages or density-weighted region averages, with largest deviations obtained when the density is non-uniform. The average absorbed doses calculated across all tumors are similar when comparing mass-weighted and volume-weighted averages but these differ substantially from unweighted averages. CONCLUSION Different strategies for averaging of absorbed doses within and between regions can lead to substantially different absorbed-dose estimates. At reporting of radionuclide therapy dosimetry, it is important to specify the averaging strategy applied.
Collapse
Affiliation(s)
| | | | - Gudrun Alm Carlsson
- Department of Radiation Physics, Faculty of Health Sciences, Linköping University, Linköping, Sweden
| | - Erik Larsson
- Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Carl Fredrik Warfvinge
- Division of Oncology and Pathology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Pernilla Asp
- Division of Oncology and Pathology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | | |
Collapse
|
6
|
Salman M, Guatelli S, Rosenfeld AB, Malaroda A. Assessment of cross-dose contributions from tumors within computational phantoms using a Geant4 radiation dosimetry tool exploiting hybrid analytical/voxelised geometries. Med Phys 2023; 50:6580-6588. [PMID: 37288878 DOI: 10.1002/mp.16544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 05/03/2023] [Accepted: 05/10/2023] [Indexed: 06/09/2023] Open
Abstract
BACKGROUND Dosimetry software tools developed for Radiopharmaceutical Therapy, such as OLINDA/EXM or IDAC-Dose, account only for radiation dose to organs from radiopharmaceutical taken up in other organs. PURPOSE The aim of this study is to present a methodology, that can be applied to any voxelised computational model, able to account for cross-dose to organs from tumors of any shape and number enclosed within an organ. METHODS A Geant4 application using hybrid analytical/voxelised geometries has been developed as an extension to the ICRP110_HumanPhantom Geant4 advanced example and validated against ICRP publication 133. In this new Geant4 application, tumors are defined using the Geant4 Parallel Geometry functionality, which allows the co-existence of two independent geometries in the same Monte Carlo simulation. The methodology was validated by estimating total dose to healthy tissue from 90 Y and from 177 Lu distributed within tumors of various sizes localized within the liver of the ICRP110 adult male phantom. RESULTS Agreement of the Geant4 application with ICRP133 was within 5% when masses were adjusted for blood content. Total dose to healthy liver and to tumors was found to agree within 1% when compared to the ground truth. CONCLUSIONS The methodology presented in this work can be extended to investigate total dose to healthy tissue from systemic uptake of radiopharmaceuticals in tumors of different sizes using any voxelised computational dosimetric model.
Collapse
Affiliation(s)
- Muhammad Salman
- Centre for Medical Radiation Physics and School of Physics, University of Wollongong, Wollongong, Australia
| | - Susanna Guatelli
- Centre for Medical Radiation Physics and School of Physics, University of Wollongong, Wollongong, Australia
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
| | - Anatoly B Rosenfeld
- Centre for Medical Radiation Physics and School of Physics, University of Wollongong, Wollongong, Australia
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
| | - Alessandra Malaroda
- Centre for Medical Radiation Physics and School of Physics, University of Wollongong, Wollongong, Australia
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, Australia
- Nuclear Medicine and PET Department, Nepean Blue Mountains Local Health District, Blue Mountains, Australia
| |
Collapse
|
7
|
Brosch-Lenz J, Ke S, Wang H, Frey E, Dewaraja YK, Sunderland J, Uribe C. An International Study of Factors Affecting Variability of Dosimetry Calculations, Part 2: Overall Variabilities in Absorbed Dose. J Nucl Med 2023; 64:1109-1116. [PMID: 37024302 PMCID: PMC10315703 DOI: 10.2967/jnumed.122.265094] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 02/07/2023] [Accepted: 02/07/2023] [Indexed: 04/08/2023] Open
Abstract
Dosimetry for personalized radiopharmaceutical therapy has gained considerable attention. Many methods, tools, and workflows have been developed to estimate absorbed dose (AD). However, standardization is still required to reduce variability of AD estimates across centers. One effort for standardization is the Society of Nuclear Medicine and Molecular Imaging 177Lu Dosimetry Challenge, which comprised 5 tasks (T1-T5) designed to assess dose estimate variability associated with the imaging protocol (T1 vs. T2 vs. T3), segmentation (T1 vs. T4), time integration (T4 vs. T5), and dose calculation (T5) steps of the dosimetry workflow. The aim of this work was to assess the overall variability in AD calculations for the different tasks. Methods: Anonymized datasets consisting of serial planar and quantitative SPECT/CT scans, organ and lesion contours, and time-integrated activity maps of 2 patients treated with 177Lu-DOTATATE were made available globally for participants to perform dosimetry calculations and submit their results in standardized submission spreadsheets. The data were carefully curated for formal mistakes and methodologic errors. General descriptive statistics for ADs were calculated, and statistical analysis was performed to compare the results of different tasks. Variability in ADs was measured using the quartile coefficient of dispersion. Results: ADs to organs estimated from planar imaging protocols (T2) were lower by about 60% than those from pure SPECT/CT (T1), and the differences were statistically significant. Importantly, the average differences in dose estimates when at least 1 SPECT/CT acquisition was available (T1, T3, T4, T5) were within ±10%, and the differences with respect to T1 were not statistically significant for most organs and lesions. When serial SPECT/CT images were used, the quartile coefficients of dispersion of ADs for organs and lesions were on average less than 20% and 26%, respectively, for T1; 20% and 18%, respectively, for T4 (segmentations provided); and 10% and 5%, respectively, for T5 (segmentation and time-integrated activity images provided). Conclusion: Variability in ADs was reduced as segmentation and time-integration data were provided to participants. Our results suggest that SPECT/CT-based imaging protocols generate more consistent and less variable results than planar imaging methods. Effort at standardizing segmentation and fitting should be made, as this may substantially reduce variability in ADs.
Collapse
Affiliation(s)
- Julia Brosch-Lenz
- Department of Integrative Oncology, BC Cancer Research Institute, Vancouver, British Columbia, Canada
| | - Suqi Ke
- Division of Quantitative Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Hao Wang
- Division of Quantitative Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Eric Frey
- Rapid, LLC, Baltimore, Maryland
- Department of Radiology, Johns Hopkins University, Baltimore, Maryland
| | - Yuni K Dewaraja
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - John Sunderland
- Department of Radiology, University of Iowa, Iowa City, Iowa
| | - Carlos Uribe
- Department of Integrative Oncology, BC Cancer Research Institute, Vancouver, British Columbia, Canada;
- Department of Functional Imaging, BC Cancer, Vancouver, British Columbia, Canada; and
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
8
|
Chen G, Lu Z, Chen Y, Mok GSP. Voxel-S-value methods adapted to heterogeneous media for quantitative Y-90 microsphere radioembolization dosimetry. Z Med Phys 2023; 33:35-45. [PMID: 36535831 PMCID: PMC10068576 DOI: 10.1016/j.zemedi.2022.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 11/07/2022] [Accepted: 11/07/2022] [Indexed: 12/23/2022]
Abstract
PURPOSE The absorbed dose estimation from Voxel-S-Value (VSV) method in heterogeneous media is suboptimal as VSVs are calculated in homogeneous media. The aim of this study is to develop and evaluate new VSV methods in order to enhance the accuracy of Y-90 microspheres absorbed dose estimation in liver, lungs, tumors and lung-liver interface regions. METHODS Ten patients with Y-90 microspheres SPECT/CT and PET/CT data, six of whom had additional Tc-99m-macroaggregated albumin SPECT/CT data, were analyzed from the Deep Blue Data Repository. Seven existing VSV methods along with three newly proposed VSV methods were evaluated: liver and lung kernel with center voxel scaling (LiLuCK), liver kernel with density correction and lung kernel with center voxel scaling (LiKDLuCK), liver kernel with center voxel scaling and lung kernel with density correction (LiCKLuKD). Monte Carlo (MC) results were regarded as the gold standard. Absolute absorbed dose errors (%AADE) of these methods for the liver, lungs, tumors, upper liver, and lower lungs were assessed. RESULTS Liver and tumor's median %AADE of all methods were <3% for three types of imaging data. In the lungs, however, three recently proposed VSV methods provided median %AADEs of less than 7%, whereas the differences exceeded 20% for existing methods that did not use a lung kernel. LiCKLuKD could achieve median %AADE <2% in the liver, upper liver and tumors, and median %AADE <7% in the lungs and lower lungs in three types of data. CONCLUSION All methods are consistent with MC in the liver and tumors. Methods with tissue-specific kernel and effective correction achieve smaller errors in lungs. LiCKLuKD has comparable results with MC in absorbed dose estimation of Y-90 radioembolization for all target regions.
Collapse
Affiliation(s)
- Gefei Chen
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, China
| | - Zhonglin Lu
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, China; Center for Cognitive and Brain Sciences, Institute of Collaborative Innovation, University of Macau, Taipa, Macau SAR, China
| | - Yue Chen
- Department of Nuclear Medicine, The Affiliated Hospital of Southwest Medical University, Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province. No. 25, Taiping St., Luzhou, Sichuan, China.
| | - Greta S P Mok
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, China; Center for Cognitive and Brain Sciences, Institute of Collaborative Innovation, University of Macau, Taipa, Macau SAR, China; Ministry of Education Frontiers Science Center for Precision Oncology, University of Macau, Macau SAR, China.
| |
Collapse
|
9
|
Vergnaud L, Giraudet AL, Moreau A, Salvadori J, Imperiale A, Baudier T, Badel JN, Sarrut D. Patient-specific dosimetry adapted to variable number of SPECT/CT time-points per cycle for [Formula: see text]Lu-DOTATATE therapy. EJNMMI Phys 2022; 9:37. [PMID: 35575946 PMCID: PMC9110613 DOI: 10.1186/s40658-022-00462-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 04/20/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The number of SPECT/CT time-points is important for accurate patient dose estimation in peptide receptor radionuclide therapy. However, it may be limited by the patient's health and logistical reasons. Here, an image-based dosimetric workflow adapted to the number of SPECT/CT acquisitions available throughout the treatment cycles was proposed, taking into account patient-specific pharmacokinetics and usable in clinic for all organs at risk. METHODS Thirteen patients with neuroendocrine tumors were treated with four injections of 7.4 GBq of [Formula: see text]Lu-DOTATATE. Three SPECT/CT images were acquired during the first cycle (1H, 24H and 96H or 144H post-injection) and a single acquisition (24H) for following cycles. Absorbed doses were estimated for kidneys (LK and RK), liver (L), spleen (S), and three surrogates of bone marrow (L2 to L4, L1 to L5 and T9 to L5) that were compared. 3D dose rate distributions were computed with Monte Carlo simulations. Voxel dose rates were averaged at the organ level. The obtained Time Dose-Rate Curves (TDRC) were fitted with a tri-exponential model and time-integrated. This method modeled patient-specific uptake and clearance phases observed at cycle 1. Obtained fitting parameters were reused for the following cycles, scaled to the measure organ dose rate at 24H. An alternative methodology was proposed when some acquisitions were missing based on population average TDRC (named STP-Inter). Seven other patients with three SPECT/CT acquisitions at cycles 1 and 4 were included to estimate the uncertainty of the proposed methods. RESULTS Absorbed doses (in Gy) per cycle available were: 3.1 ± 1.1 (LK), 3.4 ± 1.5 (RK), 4.5 ± 2.8 (L), 4.6 ± 1.8 (S), 0.3 ± 0.2 (bone marrow). There was a significant difference between bone marrow surrogates (L2 to L4 and L1 to L5, Wilcoxon's test: p value < 0.05), and while depicting very doses, all three surrogates were significantly different than dose in background (p value < 0.01). At cycle 1, if the acquisition at 24H is missing and approximated, medians of percentages of dose difference (PDD) compared to the initial tri-exponential function were inferior to 3.3% for all organs. For cycles with one acquisition, the median errors were smaller with a late time-point. For STP-Inter, medians of PDD were inferior to 7.7% for all volumes, but it was shown to depend on the homogeneity of TDRC. CONCLUSION The proposed workflow allows the estimation of organ doses, including bone marrow, from a variable number of time-points acquisitions for patients treated with [Formula: see text]Lu-DOTATATE.
Collapse
Affiliation(s)
- Laure Vergnaud
- CREATIS, CNRS UMR 5220, INSERM U 1044, Université de Lyon, INSA-Lyon, Université Lyon 1, Lyon, France
- Centre de lutte contre le cancer Léon Bérard, Lyon, France
| | | | - Aurélie Moreau
- Centre de lutte contre le cancer Léon Bérard, Lyon, France
| | - Julien Salvadori
- ICANS - Institut de cancérologie Strasbourg Europe, Strasbourg, France
| | - Alessio Imperiale
- ICANS - Institut de cancérologie Strasbourg Europe, Strasbourg, France
| | - Thomas Baudier
- CREATIS, CNRS UMR 5220, INSERM U 1044, Université de Lyon, INSA-Lyon, Université Lyon 1, Lyon, France
- Centre de lutte contre le cancer Léon Bérard, Lyon, France
| | | | - David Sarrut
- CREATIS, CNRS UMR 5220, INSERM U 1044, Université de Lyon, INSA-Lyon, Université Lyon 1, Lyon, France
- Centre de lutte contre le cancer Léon Bérard, Lyon, France
| |
Collapse
|
10
|
Amato E, Gnesin S, Cicone F, Auditore L. Fundamentals of internal radiation dosimetry. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00142-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
|
11
|
Auditore L, Pistone D, Amato E, Italiano A. Monte Carlo methods in nuclear medicine. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00136-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
|
12
|
Kennedy J, Chicheportiche A, Keidar Z. Quantitative SPECT/CT for dosimetry of peptide receptor radionuclide therapy. Semin Nucl Med 2021; 52:229-242. [PMID: 34911637 DOI: 10.1053/j.semnuclmed.2021.11.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Neuroendocrine tumors (NETs) are uncommon malignancies of increasing incidence and prevalence. As these slow growing tumors usually overexpress somatostatin receptors (SSTRs), the use of 68Ga-DOTA-peptides (gallium-68 chelated with dodecane tetra-acetic acid to somatostatin), which bind to the SSTRs, allows for PET based imaging and selection of patients for peptide receptor radionuclide therapy (PRRT). PRRT with radiolabeled somatostatin analogues such as 177Lu-DOTATATE (lutetium-177-[DOTA,Tyr3]-octreotate), is mainly used for the treatment of metastatic or inoperable NETs. However, PRRT is generally administered at a fixed injected activity in order not to exceed dose limits in critical organs, which is suboptimal given the variability in radiopharmaceutical uptake among patients. Advances in SPECT (single photon emission computed tomography) imaging enable the absolute quantitative measure of the true radiopharmaceutical distribution providing for PRRT dosimetry in each patient. Personalized PRRT based on patient-specific dosimetry could improve therapeutic efficacy by optimizing effective tumor absorbed dose while limiting treatment related radiotoxicity.
Collapse
Affiliation(s)
- John Kennedy
- Department of Nuclear Medicine, Rambam Health Care Campus, Haifa, Israel; B. Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
| | - Alexandre Chicheportiche
- Department of Nuclear Medicine and Biophysics, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, Israel
| | - Zohar Keidar
- Department of Nuclear Medicine, Rambam Health Care Campus, Haifa, Israel; B. Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
| |
Collapse
|
13
|
Nautiyal A, Jha AK, Mithun S, Shetye B, Kameswaran M, Shah S, Rangarajan V, Gupta S. Analysis of absorbed dose in radioimmunotherapy with 177Lu-trastuzumab using two different imaging scenarios: a pilot study. Nucl Med Commun 2021; 42:1382-1395. [PMID: 34406146 DOI: 10.1097/mnm.0000000000001472] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVES Internal organ dosimetry is an important procedure to demonstrate the reliable application of 177Lu-trastuzumab radioimmunotherapy for human epidermal growth factor receptor-positive metastatic breast cancers. We are reporting the first human dosimetry study for 177Lu-trastuzumab. Another objective of our study was to calculate and compare the absorbed doses for normal organs and tumor lesions in patients before radioimmunotherapy with 177Lu-trastuzumab using two different imaging scenarios. METHODS Eleven patients (48.27 ± 8.95 years) with a history of metastatic breast cancer were included in the study. Postadministration of 177Lu-trastuzumab (351.09 ± 23.89 MBq/2 mg), acquisition was performed using planar and hybrid imaging scenarios at 4, 24, 72 and 168 h. Single-photon emission computed tomography/computed tomography imaging was performed at 72 h postinjection. Acquired images were processed using Dosimetry Toolkit software for the estimation of normalized cumulated activity in organs and tumor lesions. OLINDA/EXM 2.0 software was used for absorbed dose calculation in both scenarios. RESULTS Significant difference in normalized cumulated activity and the absorbed dose is noted between two imaging scenarios for the organs and tumor lesions (P < 0.05). Mean absorbed dose (mGy/MBq) estimated from heart, lungs, liver, spleen, kidney, adrenal, pancreas and colon using planar and hybrid scenarios were 0.81 ± 0.19 and 0.63 ± 0.17; 0.75 ± 0.13 and 0.32 ± 0.06; 1.26 ± 0.25 and 1.01 ± 0.17; 0.68 ± 0.22 and 0.53 ± 0.16; 0.91 ± 0.3 and 0.69 ± 0.24; 0.18 ± 0.04 and 0.11 ± 0.02; 0.25 ± 0.22 and 0.09 ± 0.02 and 0.75 ± 0.61 and 0.44 ± 0.28, respectively. CONCLUSIONS On the basis of our dosimetric evaluation, we concluded that radioimmunotherapy with 177Lu-trastuzumab is well tolerated to be implemented in routine clinical practice against HER2 positive metastatic breast cancer. Liver is the main critical organ at risk. Hybrid scenario demonstrated significantly lower absorbed doses in organs and tumors compared to the multiplanar method.
Collapse
Affiliation(s)
- Amit Nautiyal
- Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Centre, Parel
- Homi Bhabha National Institute, Mumbai, Maharashtra, India
| | - Ashish K Jha
- Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Centre, Parel
- Homi Bhabha National Institute, Mumbai, Maharashtra, India
| | - Sneha Mithun
- Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Centre, Parel
- Homi Bhabha National Institute, Mumbai, Maharashtra, India
| | - Bhakti Shetye
- Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Centre, Parel
- Homi Bhabha National Institute, Mumbai, Maharashtra, India
| | - Mythili Kameswaran
- Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Centre, Parel
- Homi Bhabha National Institute, Mumbai, Maharashtra, India
| | - Sneha Shah
- Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Centre, Parel
- Homi Bhabha National Institute, Mumbai, Maharashtra, India
| | - Venkatesh Rangarajan
- Department of Nuclear Medicine and Molecular Imaging, Tata Memorial Centre, Parel
- Homi Bhabha National Institute, Mumbai, Maharashtra, India
| | - Sudeep Gupta
- Department of Medical Oncology, Advanced Centre for Treatment, Research and Education in Cancer (ACTREC)
- Homi Bhabha National Institute, Mumbai, Maharashtra, India
| |
Collapse
|
14
|
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.
Collapse
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
| |
Collapse
|
15
|
Roncali E, Capala J, Benedict SH, Akabani G, Bednarz B, Bhadrasain V, Bolch WE, Buchsbaum JC, Coleman NC, Dewaraja YK, Frey E, Ghaly M, Grudzinski J, Hobbs RF, Howell RW, Humm JL, Kunos CA, Larson S, Lin FI, Madsen M, Mirzadeh S, Morse D, Pryma D, Sgouros G, St James S, Wahl RL, Xiao Y, Zanzonico P, Zukotynski K. Overview of the First NRG Oncology-National Cancer Institute Workshop on Dosimetry of Systemic Radiopharmaceutical Therapy. J Nucl Med 2021; 62:1133-1139. [PMID: 33277396 PMCID: PMC8833877 DOI: 10.2967/jnumed.120.255547] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 11/20/2021] [Indexed: 11/16/2022] Open
Abstract
In 2018, the National Cancer Institute and NRG Oncology partnered for the first time to host a joint workshop on systemic radiopharmaceutical therapy (RPT) to specifically address dosimetry issues and strategies for future clinical trials. The workshop focused on current dosimetric approaches for clinical trials, strategies under development that would optimize dose reporting, and future desired or optimized approaches for novel emerging radionuclides and carriers in development. In this article, we review the main approaches that are applied clinically to calculate the absorbed dose. These include absorbed doses calculated over a variety of spatial scales, including whole body, organ, suborgan, and voxel, the last 3 of which are achievable within the MIRD schema (S value) and can be calculated with analytic methods or Monte Carlo methods, the latter in most circumstances. This article will also contrast currently available methods and tools with those used in the past, to propose a pathway whereby dosimetry helps the field by optimizing the biologic effect of the treatment and trial design in the drug approval process to reduce financial and logistical costs. We also briefly discuss the dosimetric equivalent of biomarkers to help bring a precision medicine approach to RPT implementation when merited by evidence collected during early-phase trial investigations. Advances in the methodology and related tools have made dosimetry the optimum biomarker for RPT.
Collapse
Affiliation(s)
| | | | | | | | - Bryan Bednarz
- University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
| | | | - Wesley E Bolch
- Department of Biomedical Engineering, University of Florida, Gainesville, Florida
| | | | | | | | - Eric Frey
- Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland
| | - Michael Ghaly
- Radiopharmaceutical Imaging and Dosimetry LLC (Rapid), Baltimore, Maryland
| | | | - Robert F Hobbs
- Department of Radiation Oncology, Johns Hopkins University, Baltimore, Maryland
| | - Roger W Howell
- Department of Radiology, Rutgers University, Newark, New Jersey
| | - John L Humm
- Memorial Sloan Kettering Cancer Center, New York, New York
| | | | - Steve Larson
- Memorial Sloan Kettering Cancer Center, New York, New York
| | | | | | | | | | - Daniel Pryma
- University of Pennsylvania, Philadelphia, Pennsylvania
| | - George Sgouros
- Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland
| | - Sara St James
- University of California San Francisco, San Francisco, California
| | - Richard L Wahl
- Mallinckrodt Institute of Radiology, Washington University in St. Louis, St. Louis, Missouri
| | - Ying Xiao
- University of Pennsylvania, Philadelphia, Pennsylvania
| | - Pat Zanzonico
- Memorial Sloan Kettering Cancer Center, New York, New York
| | | |
Collapse
|
16
|
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.
Collapse
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
| |
Collapse
|
17
|
Olguin E, President B, Ghaly M, Frey E, Sgouros G, Bolch WE. Specific absorbed fractions and radionuclide S-values for tumors of varying size and composition. Phys Med Biol 2020; 65:235015. [PMID: 32992308 DOI: 10.1088/1361-6560/abbc7e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Accurate estimates of tumor absorbed dose are essential for the evaluation of treatment efficacy in radiopharmaceutical cancer therapy. Although tumor dosimetry via the MIRD schema has been previously investigated, prior studies have been limited to the consideration of soft-tissue tumors. In the present study, specific absorbed fractions (SAFs) for monoenergetic photons, electrons, and alpha particles in tumors of varying compositions were computed using Monte Carlo simulations in MCNPX after which self-irradiation S-values for 22 radionuclides (along with 14 additional alpha-emitter progeny) were generated for tumors of both varying size and tissue composition. The tumors were modeled as spheres with radii ranging from 0.10 cm to 6.0 cm and with compositions varying from 100% soft tissue (ST) to 100% mineral bone (MB). The energies of the photons and electrons were varied on a logarithm energy grid from 10 keV to 10 MeV. The energies of alpha particles were varied along a linear energy grid from 0.5 MeV to 12 MeV. In all cases, a homogenous activity distribution was assumed throughout the tumor volume. Furthermore, to assess the effect of tumor shape, several ellipsoidal tumors of different compositions were modeled and absorbed fractions were computed for monoenergetic electrons and photons. S-values were then generated using detailed decay data from the 2008 MIRD Monograph on Radionuclide Data and Decay Schemes. Our study results demonstrate that a soft-tissue model yields relative errors of 25% and 71% in the absorbed fraction assigned to uniform sources of 1.5 MeV electrons and 100 keV photons, respectively, localized within a 1 cm diameter tumor of MB. The data further show that absorbed fractions for moderate ellipsoids can be well approximated by a spherical shape of equal mass within a relative error of < 8%. S-values for 22 radionuclides (and their daughter progeny) were computed with results demonstrating how relative errors in SAFs could propagate to relative errors in tumor dose estimates as high as 86%. A comprehensive data set of radionuclide S-values by tumor size and tissue composition is provided for application of the MIRD schema for tumor dosimetry in radiopharmaceutical therapy.
Collapse
Affiliation(s)
- Edmond Olguin
- J Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611-6131, United States of America
| | | | | | | | | | | |
Collapse
|
18
|
Tiwari A, Gravesa SA, Sunderland J. The Impact of Tissue Type and Density on Dose Point Kernels for Patient-Specific Voxel-Wise Dosimetry: A Monte Carlo Investigation. Radiat Res 2020; 193:531-542. [PMID: 32315249 DOI: 10.1667/rr15563.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 03/11/2020] [Indexed: 11/03/2022]
Abstract
We report the generation of dose point kernels for clinically-relevant radionuclide beta decays and monoenergetic electrons in various tissues to understand the impact of tissue type on dose point kernels. Currently available voxel-wise dosimetry approaches using dose point kernels ignore tissue composition and density heterogeneities. Therefore, the study on the impact of tissue type on dose point kernels is warranted. Simulations were performed using the GATE Monte Carlo toolkit, which encapsulates GEANT4 libraries. Dose point kernels were simulated in phantoms of water, compact bone, lung, adipose tissue, blood and red marrow for radionuclides 90Y, 188Re, 32P, 89Sr, 186Re, 153Sm and 177Lu and monoenergetic electrons (0.015-10 MeV). All simulations were performed by assuming an isotropic point source of electrons at the center of a homogeneous spherical phantom. Tissue-specific differences between kernels were investigated by normalizing kernels for effective pathlength. Transport of 20 million particles was found to provide sufficient statistical precision in all simulated kernels. The simulated dose point kernels demonstrate excellent agreement with other Monte Carlo packages. Deviation from kernels reported in the literature did not exceed a 10% global difference, which is consistent with the variability among published results. There are no significant differences between the dose point kernel in water and kernels in other tissues that have been scaled to account for density; however, tissue density predictably demonstrated itself to be a significant variable in dose point kernel distribution.
Collapse
Affiliation(s)
- Ashok Tiwari
- Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242.,Department of Physics, University of Iowa, Iowa City, Iowa 52242
| | - Stephen A Gravesa
- Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242
| | - John Sunderland
- Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242.,Department of Physics, University of Iowa, Iowa City, Iowa 52242
| |
Collapse
|
19
|
Castillo Seoane D, de Saint-Hubert M, Crabbe M, Struelens L, Koole M. Targeted alpha therapy: a critical review of translational dosimetry research with emphasis on actinium-225. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF RADIOPHARMACEUTICAL CHEMISTRY AND BIOLOGY 2020; 64:265-277. [PMID: 32441067 DOI: 10.23736/s1824-4785.20.03266-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This review provides a general overview of the current achievements and challenges in translational dosimetry for targeted alpha therapy (TAT). The concept of targeted radionuclide therapy (TRNT) is described with an overview of its clinical applicability and the added value of TAT is discussed. For TAT, we focused on actinium-225 (225Ac) as an example for alpha particle emitting radionuclides and their features, such as limited range within tissue and high linear energy transfer, which make alpha particle emissions more effective in targeted killing of tumour cells compared to beta radiation. Starting with the state-of-the-art dosimetry for TRNT and TAT, we then describe the challenges that still need to be met in order to move to a personalized dosimetry approach for TAT. Specifically for 225Ac, we discuss the recoiled daughter effect which may provoke significant damage to healthy tissue or organs and should be considered. Next, a broad overview is given of the pre-clinical research on 225Ac-TAT with an extensive description of tools which are only available in a pre-clinical setting and their added value. In addition, we review the preclinical biodistribution and dosimetry studies that have been performed on TAT-agents and more specifically of 225Ac and its multiple progeny, and describe their potential role to better characterize the pharmacokinetic (PK) profile of TAT-agents and to optimize the use of theranostic approaches for dosimetry. Finally, we discuss the support pre-clinical studies may provide in understanding dose-effect relationships, linking radiation dose quantities to biological endpoints and even moving away from macro- to microdosimetry. As such, the translation of pre-clinical findings may provide valuable information and new approaches for improved clinical dosimetry, thus paving the way to personalized TAT.
Collapse
Affiliation(s)
- Dayana Castillo Seoane
- Unit of Nuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, Katholieke Universiteit Leuven (KUL), Leuven, Belgium - .,Research Unit in Dosimetric Applications, Belgian Nuclear Research Center (SCK•CEN), Mol, Belgium -
| | - Marijke de Saint-Hubert
- Research Unit in Dosimetric Applications, Belgian Nuclear Research Center (SCK•CEN), Mol, Belgium
| | - Melissa Crabbe
- Research Unit in Dosimetric Applications, Belgian Nuclear Research Center (SCK•CEN), Mol, Belgium
| | - Lara Struelens
- Research Unit in Dosimetric Applications, Belgian Nuclear Research Center (SCK•CEN), Mol, Belgium
| | - Michel Koole
- Unit of Nuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, Katholieke Universiteit Leuven (KUL), Leuven, Belgium
| |
Collapse
|
20
|
Li T, Zhu L, Lu Z, Song N, Lin KH, Mok GSP. BIGDOSE: software for 3D personalized targeted radionuclide therapy dosimetry. Quant Imaging Med Surg 2020; 10:160-170. [PMID: 31956539 DOI: 10.21037/qims.2019.10.09] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Background Advance 3D quantitative radionuclide imaging techniques boost the accuracy of targeted radionuclide therapy (TRT) dosimetry to voxel level. The goal of this work is to develop a comprehensive 3D dosimetric software, BIGDOSE, with new features of image registration and virtual CT for patient-specific dosimetry. Methods BIGDOSE includes a portable graphical user interface written in Python, integrating (I) input of sequential ECT/CT images; (II) segmentation; (III) non-rigid image registration; (IV) curve fitting and voxel-based integration; (V) dose conversion and (VI) 3D dose analysis. The accuracy of the software was evaluated using a simulation study with 9 XCAT phantoms. We simulated SPECT/CT acquisitions at 1, 12, 24, 72 and 144-hrs post In-111 Zevalin injection with inter-scans misalignments using an analytical projector for medium energy general purpose (MEGP) collimator, modeling attenuation, scatter and collimator-detector response. The SPECT data were reconstructed using quantitative OS-EM method. A CT organ-based registration was performed before the dose calculation. Organ absorbed doses for the corresponding Y-90 therapeutic agent were calculated on target organs and compared with those obtained from OLINDA/EXM, using dose measured from GATE as the gold standard. One patient with In-111 DTPAOC injection as well as two patients with Y-90 microsphere embolization were used to demonstrate the clinical effectiveness of our software. Results In the simulation, the organ dose errors of BIGDOSE were -9.59%±9.06%, -8.36±5.82%, -23.41%±6.67%, -6.05%±2.06% for liver, spleen, kidneys and lungs, while they were -25.72%±12.52%, -14.93%±10.91%, -28.63%±12.97% and -45.30%±5.84% for OLINDA/EXM. Cumulative dose volume histograms, dose maps and iso-dose contours provided 3D dose distribution information on the simulated and patient data. Conclusions BIGDOSE provides a one-stop platform for voxel-based dose estimation with enhanced functions. It is a promising tool to streamline the current clinical TRT dosimetric practice with high accuracy, incorporating 3D personalized imaging information for improved treatment outcome.
Collapse
Affiliation(s)
- Tiantian Li
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, University of Macau, Macau SAR, China
| | - Licheng Zhu
- Department of Computer Science, Faculty of Science and Technology, University of Macau, Macau SAR, China
| | - Zhonglin Lu
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, University of Macau, Macau SAR, China
| | - Na Song
- Department of Nuclear Medicine, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York, USA
| | - Ko-Han Lin
- Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Greta S P Mok
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, University of Macau, Macau SAR, China.,Faculty of Health Sciences, Institute of Collaborative Innovation, University of Macau, Macau SAR, China.,Center for Cognitive and Brain Sciences, Institute of Collaborative Innovation, University of Macau, Macau SAR, China
| |
Collapse
|
21
|
Papadimitroulas P, Balomenos A, Kopsinis Y, Loudos G, Alexakos C, Karnabatidis D, Kagadis GC, Kostou T, Chatzipapas K, Visvikis D, Mountris KA, Jaouen V, Katsanos K, Diamantopoulos A, Apostolopoulos D. A Review on Personalized Pediatric Dosimetry Applications Using Advanced Computational Tools. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2019. [DOI: 10.1109/trpms.2018.2876562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
22
|
Gosewisch A, Ilhan H, Tattenberg S, Mairani A, Parodi K, Brosch J, Kaiser L, Gildehaus FJ, Todica A, Ziegler S, Bartenstein P, Böning G. 3D Monte Carlo bone marrow dosimetry for Lu-177-PSMA therapy with guidance of non-invasive 3D localization of active bone marrow via Tc-99m-anti-granulocyte antibody SPECT/CT. EJNMMI Res 2019; 9:76. [PMID: 31414241 PMCID: PMC6694348 DOI: 10.1186/s13550-019-0548-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 07/30/2019] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND The bone marrow (BM) is a main risk organ during Lu-177-PSMA ligand therapy of metastasized castration-resistant prostate cancer (mCRPC) patients. So far, BM dosimetry relies on S values, which are pre-computed for reference anatomies, simplified activity distributions, and a physiological BM distribution. However, mCRPC patients may show a considerable bone lesion load, which leads to a heterogeneous and patient-specific activity accumulation close to BM-bearing sites. Furthermore, the patient-specific BM distribution might be significantly altered in the presence of bone lesions. The aim was to perform BM absorbed dose calculations through Monte Carlo (MC) simulations and to investigate the potential value of image-based BM localization. This study is based on 11 Lu-177-PSMA-617 therapy cycles of 10 patients (10 first cycles), who obtained a pre-therapeutic Ga-68-PSMA-11 PET/CT; quantitative Lu-177 SPECT acquisitions of the abdomen 24 (+CT), 48, and 72 h p.i.; and a Lu-177 whole-body planar acquisition at 24 h post-therapy. Patient-specific 3D volumes of interest were segmented from the Ga-68-PSMA-11 PET/CT, filled with activity information from the Lu-177 data, and imported into the FLUKA MC code together with the patient CT. MC simulations of the BM absorbed dose were performed assuming a physiological BM distribution according to the ICRP 110 reference male (MC1) or a displacement of active BM from the direct location of bone lesions (MC2). Results were compared with those from S values (SMIRD). BM absorbed doses were correlated with the decrease of lymphocytes, total white blood cells, hemoglobin level, and platelets. For two patients, an additional pre-therapeutic Tc-99m-anti-granulocyte antibody SPECT/CT was performed for BM localization. RESULTS Median BM absorbed doses were 130, 37, and 11 mGy/GBq for MC1, MC2, and SMIRD, respectively. Significant strong correlation with the decrease of platelet counts was found, with highest correlation for MC2 (MC1: r = - 0.63, p = 0.04; MC2: r = - 0.71, p = 0.01; SMIRD: r = - 0.62, p = 0.04). For both investigated patients, BM localization via Tc-99m-anti-granulocyte antibody SPECT/CT indicated a displacement of active BM from the direct location of lesions similar to model MC2 and led to a reduction in the BM absorbed dose of 40 and 41% compared to MC1. CONCLUSION Higher BM absorbed doses were observed for MC-based models; however, for MC2, all absorbed doses were still below 2 Gy. MC1 resulted in critical values for some patients, but is suspected to yield strongly exaggerated absorbed doses by neglecting bone marrow displacement. Image-based BM localization might be beneficial, and future studies are recommended to support an improvement for the prediction of hematoxicities.
Collapse
Affiliation(s)
- Astrid Gosewisch
- 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
| | - Sebastian Tattenberg
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Andrea Mairani
- Heidelberg Ion Beam Therapy Center, University Hospital Heidelberg, Heidelberg, Germany
| | - Katia Parodi
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Garching b. München, Germany
| | - Julia Brosch
- 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
| | - Franz Josef Gildehaus
- 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
| | - Sibylle Ziegler
- 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
| | - Guido Böning
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| |
Collapse
|
23
|
K EG, R AF, F K, N AG, A B, Gh A. Estimating the Absorbed Dose of Organs in Pediatric Imaging of 99mTc-DTPATc-DTPA Radiopharmaceutical using MIRDOSE Software. J Biomed Phys Eng 2019; 9:285-294. [PMID: 31341874 PMCID: PMC6613160 DOI: 10.31661/jbpe.v0i0.984] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 10/30/2018] [Indexed: 11/26/2022]
Abstract
Introduction: In this study, organ radiation doses were calculated for the renal agent 99mTc-DTPATc-DTPA in children. Bio-kinetic energy of 99mTc-DTPATc-DTPA was evaluated
by scintigraphy and estimates for absorbed radiation dose were provided using standard medical internal radiation dosimetry (MIRD) techniques.
Material and Methods: In this applied research, fourteen children patients (6 males and 8 females) were imaged using a series of planar and SPECT images after injecting with technetium-99mTc-DTPA
diethylenetriaminepentaacetic acid (99mTc-DTPATc-DTPA). A hybrid planar/SPECT method was used to plot time-activity curves to obtain the residence time of the
source organs and also MIRDOSE software was used to calculate the absorbed dose of every organ. P-values were calculated using t-tests in order to make a comparison between the adsorbed doses of male and female groups.
Results: Mean absorbed doses (µGy/MBq) for urinary bladder wall, kidneys, gonads, liver and adrenals were 213.5±47.8, 12.97±6.23, 12.0±2.5, 4.29±1.47, and 3.31±0.96, respectively. Furthermore,
the mean effective dose was 17.5±3.7 µSv/MBq. There was not any significant difference in the mean absorbed dose of the two groups.
Conclusion: Bladder cumulated activity was the most contribution in the effective dose of patients scanned with 99mTc-DTPATc-DTPA. Using a hybrid planar/SPECT method
can cause an increase in accumulated activity accuracy for the region of interest. Moreover, patient-specified internal dosimetry is recommended.
Collapse
Affiliation(s)
- Ebrahimnejad Gorji K
- Department of Medical Physics Radiobiology and Radiation Protection, Babol University of Medical Sciences, Babol, Iran
| | - Abedi Firouzjah R
- Department of Medical Physics Radiobiology and Radiation Protection, Babol University of Medical Sciences, Babol, Iran
| | - Khanzadeh F
- Department of Medical Radiation, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Abdi-Goushbolagh N
- Department of Medical Physics, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Banaei A
- Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Ataei Gh
- Department of Radiology Technology, Faculty of Paramedical Sciences, Babol University of Medical Science, Babol, Iran
| |
Collapse
|
24
|
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.
Collapse
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.
| |
Collapse
|
25
|
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.
Collapse
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
| |
Collapse
|
26
|
Huizing DMV, de Wit-van der Veen BJ, Verheij M, Stokkel MPM. Dosimetry methods and clinical applications in peptide receptor radionuclide therapy for neuroendocrine tumours: a literature review. EJNMMI Res 2018; 8:89. [PMID: 30159614 PMCID: PMC6115319 DOI: 10.1186/s13550-018-0443-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 08/21/2018] [Indexed: 12/25/2022] Open
Abstract
Background The main challenge for systemic radiation therapy using radiopharmaceuticals (SRT) is to optimise the dose delivered to the tumour, while minimising normal tissue irradiation. Dosimetry could help to increase therapy response and decrease toxicity after SRT by individual treatment planning. Peptide receptor radionuclide therapy (PRRT) is an accepted SRT treatment option for irresectable and metastatic neuroendocrine tumours (NET). However, dosimetry in PRRT is not routinely performed, mainly due to the lack of evidence in literature and clinical implementation difficulties. The goal of this review is to provide insight in dosimetry methods and requirements and to present an overview of clinical aspects of dosimetry in PRRT for NET. Methods A PubMed query including the search criteria dosimetry, radiation dose, peptide receptor radionuclide therapy, and radionuclide therapy was performed. Articles were selected based on title and abstract, and description of dosimetric approach. Results A total of 288 original articles were included. The most important dosimetry methods, their main advantages and limitations, and implications in the clinical setting are discussed. An overview of dosimetry in clinical studies regarding PRRT treatment for NET is provided. Conclusion Clinical dosimetry in PRRT is feasible and can result in improved treatment outcomes. Current clinical dosimetry studies focus on safety and apply non-voxel-based dosimetry methods. Personalised treatment using sophisticated dosimetry methods to assess tumour and normal tissue uptake in clinical trials is the next step towards routine dosimetry in PRRT for NET. Electronic supplementary material The online version of this article (10.1186/s13550-018-0443-z) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Daphne Merel Valerie Huizing
- Department of Nuclear Medicine, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | | | - Marcel Verheij
- Department of Radiation Oncology, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | | |
Collapse
|
27
|
Gosewisch A, Delker A, Tattenberg S, Ilhan H, Todica A, Brosch J, Vomacka L, Brunegraf A, Gildehaus FJ, Ziegler S, Bartenstein P, Böning G. Patient-specific image-based bone marrow dosimetry in Lu-177-[DOTA 0,Tyr 3]-Octreotate and Lu-177-DKFZ-PSMA-617 therapy: investigation of a new hybrid image approach. EJNMMI Res 2018; 8:76. [PMID: 30076556 PMCID: PMC6081875 DOI: 10.1186/s13550-018-0427-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 07/16/2018] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND The bone marrow (BM) is a main organ at risk in Lu-177-PSMA-617 therapy of prostate cancer and Lu-177-Octreotate therapy of neuroendocrine tumours. BM dosimetry is challenging and time-consuming, as different sequential quantitative measurements must be combined. The BM absorbed dose from the remainder of the body (ROB) can be determined from sequential whole-body planar (WB-P) imaging, while quantitative Lu-177-SPECT allows for more robust tumour and organ absorbed doses. The aim was to investigate a time-efficient and patient-friendly hybrid protocol (HP) for the ROB absorbed dose to the BM. It combines three abdominal quantitative SPECT (QSPECT) scans with a single WB-P acquisition and was compared with a reference protocol (RP) using sequential WB-P in combination with sequential QSPECT images. We investigated five patients receiving 7.4 GBq Lu-177-Octreotate and five patients treated with 3.7 GBq Lu-177-PSMA-617. Each patient had WB-P and abdominal SPECT acquisitions 24 (+ CT), 48, and 72 h post-injection. Blood samples were drawn 30 min, 80 min, 24 h, 48 h, and 72 h post-injection. BM absorbed doses from the ROB were estimated from sequential WB-P images (RP), via a mono-exponential fit and mass-scaled organ-level S values. For the HP, a mono-exponential fit on the QSPECT data was scaled with the activity of one WB-P image acquired either 24, 48, or 72 h post-injection (HP24, HP48, HP72). Total BM absorbed doses were determined as a sum of ROB, blood, major organ, and tumour contributions. RESULTS Compared with the RP and for Lu-177-Octreotate therapy, median differences of the total BM absorbed doses were 13% (9-17%), 8% (4-15%), and 1% (0-5%) for the HP24, HP48, and HP72, respectively. For Lu-177-PSMA-617 therapy, total BM absorbed doses deviated 10% (2-20%), 3% (0-6%), and 2% (0-6%). CONCLUSION For both Lu-177-Octreotate and Lu-177-PSMA-617 therapy, BM dosimetry via sequential QSPECT imaging and a single WB-P acquisition is feasible, if this WB-P image is acquired at a late time point (48 or 72 h post-injection). The reliability of the HP can be well accepted considering the uncertainties of quantitative Lu-177 imaging and BM dosimetry using standardised organ-level S values.
Collapse
Affiliation(s)
- Astrid Gosewisch
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Andreas Delker
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Sebastian Tattenberg
- 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
| | - Andrei Todica
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Julia Brosch
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Lena Vomacka
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| | - Anika Brunegraf
- 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
| | - Sibylle Ziegler
- 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
| | - Guido Böning
- Department of Nuclear Medicine, University Hospital, LMU Munich, Marchioninistrasse 15, 81377 Munich, Germany
| |
Collapse
|
28
|
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.
Collapse
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
| |
Collapse
|
29
|
Trifunctional PSMA-targeting constructs for prostate cancer with unprecedented localization to LNCaP tumors. Eur J Nucl Med Mol Imaging 2018; 45:1841-1851. [PMID: 29623376 DOI: 10.1007/s00259-018-4004-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 03/26/2018] [Indexed: 12/11/2022]
Abstract
PURPOSE Treatment of late-stage prostate cancer by targeted radiotherapeutics such as 131I-MIP-1095 and 177Lu-PSMA-617 has shown encouraging early results. Lu-177 is preferred to I-131 in clinical settings, but targeted radioligand therapy (RLT) with 177Lu-PSMA-617 has not reached its full potential due to insufficient dose delivery to the tumor. We recently developed a dual-targeting radioiodinated ligand, RPS-027, that targets PSMA and uses albumin binding to enable good tumor uptake and significantly reduced kidney uptake in a preclinical model. Further development of this ligand is limited by the inability to independently modify PSMA and albumin binding and the requirement of I-131 for therapeutic application. We therefore sought to devise a new class of trifunctional ligands for RLT with (1) a high-affinity PSMA-binding domain, (2) an albumin-binding group (ABG), and (3) a chelator for radiometals such as 68Ga3+, 177Lu3+ and 225Ac3+. METHODS Ligands incorporating a triazolylphenylurea-containing PSMA-targeting group, an Nε-(2-(4-iodophenyl)acetyl)lysine ABG and the bifunctional chelator p-SCN-Bn-DOTA linked by a PEG-containing polymer containing 0,3,4,6,8 or 12 repeats were prepared. PSMA affinity was determined in LNCaP cells and uptake and tissue distribution was studied in mice bearing LNCaP tumor xenografts and compared to 177Lu-PSMA-617. Imaging studies were performed up to 24 h post-injection (p.i.) using 66Ga3+ and biodistribution studies at 4 h, 24 h and 96 h p.i. with 177Lu3+. RESULTS PSMA affinity was high (IC50 = 1-10 nM) and inversely proportional to the linker length. Tumor uptake correlated with binding affinity and was significantly greater than for 177Lu-PSMA-617 over 96 h. The highest uptake was achieved with 177Lu-RPS-063 (30.0 ± 6.9 %ID/g; 4 h p.i.). Kidney uptake was generally high, with the exception of the lowest affinity ligand 177Lu-RPS-067. Each of the compounds showed slower blood clearance than 177Lu-PSMA-617, with clearance proportional to linker length. CONCLUSIONS The high tumor uptake achieved with these trifunctional ligands predicts larger (up to 4×) doses delivered to the tumor than can be achieved with 177Lu-PSMA-617. Although PSMA-mediated kidney uptake was also observed, the exceptional area under the curve (AUC) in the tumor warrants further investigation of these novel ligands as candidates for RLT.
Collapse
|
30
|
Bagheri M, Parach AA, Razavi-Ratki SK, Nafisi-Moghadam R, Jelodari MA. PATIENT-SPECIFIC DOSIMETRY FOR PEDIATRIC IMAGING OF 99mTc-DIMERCAPTOSUCCINIC ACID WITH GATE MONTE CARLO CODE. RADIATION PROTECTION DOSIMETRY 2018; 178:213-222. [PMID: 28981712 DOI: 10.1093/rpd/ncx101] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 07/12/2017] [Indexed: 06/07/2023]
Abstract
In this study, radiation absorbed dose of 99mTc-dimercaptosuccinic acid (DMSA) in critical organs was calculated using Monte Carlo simulation. Ten child patients with genitourinary abnormalities were imaged using a series of planar, SPECT and MRI, after injection with 99mTc-DMSA. Patient-specific organ segmentation was performed on MRI and used as input in GATE. Organs with substantial uptake included kidneys, bladder and liver. The mean organ absorbed dose coefficients (mGy/MBq) were 0.063, 0.058, 0.018, 0.016, 0.013 and 0.010 for the right kidney, left kidney, bones, urinary bladder wall, liver and gonads, respectively. The absorbed dose coefficients in the remainder of the body was 0.012 mGy/MBq. The authors implemented an image-based Monte Carlo method for patient-specific 3D absorbed dose calculation. This study also demonstrates the possibility to obtain patient-specific attenuation map from MRI to be used for the simulations of radiation transport and energy deposition in phantom using Monte Carlo methods.
Collapse
Affiliation(s)
- Mahmoud Bagheri
- Department of Medical Physics, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Ali Asghar Parach
- Department of Medical Physics, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Seid Kazem Razavi-Ratki
- Department of Radiology, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Reza Nafisi-Moghadam
- Department of Radiology, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | | |
Collapse
|
31
|
Hou X, Birkenfeld B, Piwowarska-Bilska H, Celler A. Patient-specific dosimetry of 99mTc-HYNIC-Tyr 3-Octreotide in children. EJNMMI Phys 2017; 4:24. [PMID: 29030760 PMCID: PMC5640560 DOI: 10.1186/s40658-017-0191-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 10/04/2017] [Indexed: 02/03/2023] Open
Abstract
Background Technetium-99m-hydrazinonicotinamide-Tyr3-octreotide (99mTc-HYNIC-TOC) is recognized as a promising radiopharmaceutical for diagnosing neuroendocrine tumors (NETs). However, 99mTc-HYNIC-TOC dosimetry has been investigated only for adults. As pediatric radionuclide therapies become increasingly common, similar dosimetric studies for children are urgently needed. The aim of this study is to report personalized image-based biodistributions and dosimetry evaluations for children studies performed using 99mTc-HYNIC-TOC and to compare them with those from adult subjects. Eleven children/teenage patients with suspected or diagnosed NETs were enrolled. Patient imaging included a series of 2–3 whole-body planar scans and SPECT/CT performed over 2–24 h after the 99mTc-HYNIC-TOC injections. The time-integrated activity coefficients (TIACs) were obtained from the hybrid planar/SPECT technique. Patient-specific doses were calculated using both the voxel-level and the organ-level approaches. Estimated children doses were compared with adults’ dosimetry. Results Pathologic uptake was observed in five patients. TIACs for normal organs with significant uptakes, i.e., kidneys, spleen, and liver, were similar to adults’ TIACs. Using the voxel-level approach, the average organ doses for children were 0.024 ± 0.009, 0.032 ± 0.017, and 0.017 ± 0.007 mGy/MBq for the kidneys, spleen, and liver, respectively, which were 30% larger than adults’ doses. Similar values were obtained from the organ-level dosimetry when using OLINDA with adapted organ masses. Tumor doses were 0.010–0.024 mGy/MBq. However, cross-organ contributions were much larger in children than in adults, comprising about 15–40% of the total organ/tumor doses. No statistical differences were found between mean doses and dose distributions in patients with and without pathologic uptakes. Conclusion Although the children TIACs were similar to those in adults, their doses were about 30% higher. No significant correlation was found between the children’s doses and their ages. However, substantial inter-patient variability in radiotracer uptake, indicating disparity in expression of somatostatin receptor between different patients, emphasizes the importance and necessity of patient-specific dosimetry for clinical studies.
Collapse
Affiliation(s)
- Xinchi Hou
- Medical Imaging Research Group, Department of Radiology, University of British Columbia, 828 West 10th Avenue, Rm 366, Vancouver, BC, V5Z1L8, Canada
| | - Bozena Birkenfeld
- Nuclear Medicine Department, Pomeranian Medical University, Szczecin, Poland
| | | | - Anna Celler
- Medical Imaging Research Group, Department of Radiology, University of British Columbia, 828 West 10th Avenue, Rm 366, Vancouver, BC, V5Z1L8, Canada.
| |
Collapse
|
32
|
Sarrut D, Badel JN, Halty A, Garin G, Perol D, Cassier P, Blay JY, Kryza D, Giraudet AL. 3D absorbed dose distribution estimated by Monte Carlo simulation in radionuclide therapy with a monoclonal antibody targeting synovial sarcoma. EJNMMI Phys 2017; 4:6. [PMID: 28101733 PMCID: PMC5241566 DOI: 10.1186/s40658-016-0172-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 12/28/2016] [Indexed: 11/10/2022] Open
Abstract
Backround Radiolabeled OTSA101, a monoclonal antibody targeting synovial sarcoma (SS) developed by OncoTherapy Science, was used to treat relapsing SS metastases following a theranostic procedure: in case of significant 111In-OTSA101 tumor uptake and favorable biodistribution, patient was randomly treated with 370/1110 MBq 90Y-OTSA101. Monte Carlo-based 3D dosimetry integrating time-activity curves in VOI was performed on 111In-OTSA101 repeated SPECT/CT. Estimated absorbed doses (AD) in normal tissues were compared to biological side effects and to the admitted maximal tolerated absorbed dose (MTD) in normal organs. Results in the tumors were also compared to disease evolution. Results Biodistribution and tracer quantification were analyzed on repeated SPECT/CT acquisitions performed after injection of 111In-OTSA101 in 19/20 included patients. SPECT images were warped to a common coordinates system with deformable registration. Volumes of interest (VOI) for various lesions and normal tissues were drawn on the first CT acquisition and reported to all the SPECT images. Tracer quantification and residence time of 111In-OTSA101 in VOI were used to evaluate the estimated absorbed doses per MBq of 90Y-OTSA101 by means of Monte Carlo simulations (GATE). A visual scale analysis was applied to assess tumor uptake (grades 0 to 4) and results were compared to the automated quantification. Results were then compared to biological side effects reported in the selected patients treated with 90Y-OTSA101 but also to disease response to treatment. After screening, 8/20 patients were treated with 370 or 1110 MBq 90Y-OTSA101. All demonstrated medullary toxicity, only one presented with transient grade 3 liver toxicity due to disease progression, and two patients presented with transient grade 1 renal toxicity. Median absorbed doses were the highest in the liver (median, 0.64 cGy/MBq; [0.27 −1.07]) being far lower than the 20 Gy liver MTD, and the lowest in bone marrow (median, 0.09 cGy/MBq; [0.02 −0.18]) being closer to the 2 Gy bone marrow MTD. Most of the patients demonstrated progressive disease on RECIST criteria during patient follow-up. 111In-OTSA101 tumors tracer uptake visually appeared highly heterogeneous in inter- and intra-patient analyses, independently of tumor sizes, with variable kinetics. The majority of visual grades corresponded to the automated computed ones. Estimated absorbed doses in the 95 supra-centimetric selected lesions ranged from 0.01 to 0.71 cGy per injected MBq (median, 0.22 cGy/MBq). The maximal tumor AD obtained was 11.5 Gy. Conclusions 3D dosimetry results can explain the observed toxicity and tumors response. Despite an intense visual 111In-OTSA101 liver uptake, liver toxicity was not the dose limiting factor conversely to bone marrow toxicity. Even though tumors 111In-OTSA101 avidity was visually obvious for treated patients, the low estimated tumors AD obtained by 3D dosimetry explain the lack of tumor response.
Collapse
Affiliation(s)
- David Sarrut
- Univ Lyon, INSA-Lyon, Université Lyon 1, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, F-69008, France. .,Univ Lyon, Centre Léon Bérard, Lyon, 69008, France.
| | | | - Adrien Halty
- Univ Lyon, INSA-Lyon, Université Lyon 1, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, F-69008, France.,Univ Lyon, Centre Léon Bérard, Lyon, 69008, France
| | | | - David Perol
- Univ Lyon, Centre Léon Bérard, Lyon, 69008, France
| | | | | | - David Kryza
- Univ Lyon, Université Lyon 1, CNRS, LAGEP UMR 5007, Lyon, F-69008, France.,Hospices Civils de Lyon, Imthernat plateform, Lyon, F-69008, France
| | | |
Collapse
|
33
|
Siman W, Mawlawi OR, Mikell JK, Mourtada F, Kappadath SC. Effects of image noise, respiratory motion, and motion compensation on 3D activity quantification in count-limited PET images. Phys Med Biol 2016; 62:448-464. [DOI: 10.1088/1361-6560/aa5088] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
34
|
Berenato S, Amato E, Fischer A, Baldari S. Influence of voxel S factors on three-dimensional internal dosimetry calculations. Phys Med 2016; 32:1259-1262. [DOI: 10.1016/j.ejmp.2016.09.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 08/03/2016] [Accepted: 09/15/2016] [Indexed: 11/24/2022] Open
|
35
|
Quinn B, Dauer Z, Pandit-Taskar N, Schoder H, Dauer LT. Radiation dosimetry of 18F-FDG PET/CT: incorporating exam-specific parameters in dose estimates. BMC Med Imaging 2016; 16:41. [PMID: 27317478 PMCID: PMC4912712 DOI: 10.1186/s12880-016-0143-y] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 06/02/2016] [Indexed: 11/26/2022] Open
Abstract
Background Whole body fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) is the standard of care in oncologic diagnosis and staging, and patient radiation dose must be well understood to balance exam benefits with the risk from radiation exposure. Although reference PET/CT patient doses are available, the potential for widely varying total dose prompts evaluation of clinic-specific patient dose. The aims of this study were to use exam-specific information to characterize the radiation dosimetry of PET/CT exams that used two different CT techniques for adult oncology patients and evaluate the practicality of employing an exam-specific approach to dose estimation. Methods Whole body PET/CT scans from two sets of consecutive adult patients were retrospectively reviewed. One set received a PET scan with a standard registration CT and the other a PET scan with a diagnostic quality CT. PET dose was calculated by modifying the standard reference phantoms in OLINDA/EXM 1.1 with patient-specific organ mass. CT dose was calculated using patient-specific data in ImPACT. International Commission on Radiological Protection publication 103 tissue weighting coefficients were used for effective dose. Results One hundred eighty three adult scans were evaluated (95 men, 88 women). The mean patient-specific effective dose from a mean injected 18F-FDG activity of 450 ± 32 MBq was 9.0 ± 1.6 mSv. For all standard PET/CT patients, mean effective mAs was 39 ± 11 mAs, mean CT effective dose was 5.0 ± 1.0 mSv and mean total effective dose was 14 ± 1.3 mSv. For all diagnostic PET/CT patients, mean effective mAs was 120 ± 51 mAs, mean CT effective dose was 15.4 ± 5.0 mSv and mean total effective dose was 24.4 ± 4.3 mSv. The five organs receiving the highest organ equivalent doses in all exams were bladder, heart, brain, liver and lungs. Conclusions Patient-specific parameters optimize the patient dosimetry utilized in the medical justification of whole body PET/CT referrals and optimization of PET and CT acquisition parameters. Incorporating patient-specific data into dose estimates is a worthwhile effort for characterizing patient dose, and the specific dosimetric information assists in the justification of risk and optimization of PET/CT.
Collapse
Affiliation(s)
- Brian Quinn
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA.
| | - Zak Dauer
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA
| | - Neeta Pandit-Taskar
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, USA
| | - Heiko Schoder
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, USA
| | - Lawrence T Dauer
- Department of Medical Physics, Box 84, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA.,Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, USA
| |
Collapse
|
36
|
Liu D, Khong PL, Gao Y, Mahmood U, Quinn B, St Germain J, Xu XG, Dauer LT. Radiation Dosimetry of Whole-Body Dual-Tracer 18F-FDG and 11C-Acetate PET/CT for Hepatocellular Carcinoma. J Nucl Med 2016; 57:907-12. [PMID: 26823568 PMCID: PMC5556938 DOI: 10.2967/jnumed.115.165944] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Accepted: 01/04/2016] [Indexed: 12/26/2022] Open
Abstract
UNLABELLED Combined whole-body dual-tracer ((18)F-FDG and (11)C-acetate) PET/CT is increasingly used for staging hepatocellular carcinoma, with only limited studies investigating the radiation dosimetry data of these scans. The aim of the study was to characterize the radiation dosimetry of combined whole-body dual-tracer PET/CT protocols. METHODS Consecutive adult patients with hepatocellular carcinoma who underwent whole-body dual-tracer PET/CT scans were retrospectively reviewed with institutional review board approval. OLINDA/EXM 1.1 was used to estimate patient-specific internal dose exposure in each organ. Biokinetic models for (18)F-FDG and (11)C-acetate as provided by ICRP (International Commission on Radiological Protection) publication 106 were used. Standard reference phantoms were modified to more closely represent patient-specific organ mass. With patient-specific parameters, organ equivalent doses from each CT series were estimated using VirtualDose. Dosimetry capabilities for tube current modulation protocols were applied by integrating with the latest anatomic realistic models. Effective dose was calculated using ICRP publication 103 tissue-weighting coefficients for adult male and female, respectively. RESULTS Fourteen scans were evaluated (12 men, 2 women; mean age ± SD, 60 ± 19.48 y). The patient-specific effective dose from (18)F-FDG and (11)C-acetate was 6.08 ± 1.49 and 1.56 ± 0.47 mSv, respectively, for male patients and 6.62 ± 1.38 and 1.79 ± 0.12 mSV, respectively, for female patients. The patient-specific effective dose of the CT component, which comprised 2 noncontrast whole-body scans, to male and female patients was 21.20 ± 8.94 and 14.79 ± 3.35 mSv, respectively. Thus, the total effective doses of the combined whole-body dual-tracer PET/CT studies for male and female patients were 28.84 ± 10.18 and 23.19 ± 4.61 mSv, respectively. CONCLUSION Patient-specific parameters allow for more accurate estimation of organ equivalent doses. Considering the substantial radiation dose incurred, judicious medical justification is required with every whole-body dual-tracer PET/CT referral. Although radiation risks may have less impact for the population with cancer because of their reduced life expectancy, the information is of interest and relevant for both justification, to evaluate risk/benefit, and protocol optimization.
Collapse
Affiliation(s)
- Dan Liu
- Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Pek-Lan Khong
- Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Yiming Gao
- Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, New York
| | - Usman Mahmood
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York; and
| | - Brian Quinn
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York; and
| | - Jean St Germain
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York; and
| | - X George Xu
- Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, New York
| | - Lawrence T Dauer
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York; and Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| |
Collapse
|
37
|
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.
Collapse
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
| |
Collapse
|
38
|
Máthé D, Szigeti K, Hegedűs N, Horváth I, Veres DS, Kovács B, Szűcs Z. Production and in vivo imaging of (203)Pb as a surrogate isotope for in vivo (212)Pb internal absorbed dose studies. Appl Radiat Isot 2016; 114:1-6. [PMID: 27156049 DOI: 10.1016/j.apradiso.2016.04.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 03/29/2016] [Accepted: 04/20/2016] [Indexed: 11/18/2022]
Abstract
(212)Pb is a clinically relevant therapeutic alpha emitter isotope. A surrogate, (203)Pb, if prepared with sufficiently high specific activity could be used to estimate (212)Pb in vivo absorbed doses. An improved production procedure of (203)Pb with a simple, new separation method and high specific radioactivity for imaging is reported. We determined the in-vivo biodistribution of (203)Pb in mice by SPECT/CT. This highlights application possibilities of (203)Pb for further in vivo and clinical uses (radiolabeled (212)Pb-peptide co-injection, dosimetry calculation).
Collapse
Affiliation(s)
- Domokos Máthé
- CROmed Research Centers Ltd., Baross utca 91-95, H-1047 Budapest, Hungary.
| | - Krisztián Szigeti
- Dept. of Biophysics and Radiation Biology, Semmelweis University, Tűzoltó utca 37-47, H-1094 Budapest, Hungary.
| | - Nikolett Hegedűs
- Dept. of Biophysics and Radiation Biology, Semmelweis University, Tűzoltó utca 37-47, H-1094 Budapest, Hungary.
| | - Ildikó Horváth
- Dept. of Biophysics and Radiation Biology, Semmelweis University, Tűzoltó utca 37-47, H-1094 Budapest, Hungary.
| | - Dániel S Veres
- Dept. of Biophysics and Radiation Biology, Semmelweis University, Tűzoltó utca 37-47, H-1094 Budapest, Hungary.
| | - Béla Kovács
- Institute of Food Science, University of Debrecen, Böszörményi út 138, H-4032 Debrecen, Hungary.
| | - Zoltán Szűcs
- Dept. of Cyclotron Application, MTA Atomki, Bem tér 18/c, H-4026 Debrecen, Hungary.
| |
Collapse
|