1
|
Pirayesh Islamian J, Ljungberg M. Evaluation of Improved Imaging Properties with Tungsten-Based Parallel-Hole Collimators: A Monte Carlo Study. World J Nucl Med 2024; 23:95-102. [PMID: 38933066 PMCID: PMC11199031 DOI: 10.1055/s-0044-1786165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024] Open
Abstract
Objectives The purpose of a parallel-hole collimator in a scintillation camera system is to transmit only those photons that have an emission angle close to the direction of the hole. This makes it possible to receive spatial information about the origin of the emission, that is, radioactivity decay. The dimension, shape, and intrahole thickness determine the spatial resolution and, by a tradeoff, sensitivity. The composition of the collimator material also plays an important role in determining a proper collimator. In this study, we compared tungsten alloys as a potential collimator material replacement for the conventional lead antimony material used in most of the current camera systems. Materials and Methods Monte Carlo simulations of a commercial scintillation camera system with low energy high resolution (LEHR), medium-energy (ME), and high-energy (HE) collimators of lead, tungsten, and tungsten-based alloy were simulated for different I-131, Lu-177, I-123, and Tc-99m sources, and a Deluxe rod phantom using the SIMIND Monte Carlo code. Planar images were analyzed regarding spatial resolution, image contrast in a cold source case, and system sensitivity for each collimator configuration. The hole dimensions for the three collimators were those specified in the vendor's datasheet. Results Using Pb, W, and tungsten alloy (Wolfmet) as collimator materials, the full width at half maximum (FWHM) measures for total counts (T) for LEHR with Tc-99m source (6.9, 6.8, and 6.8 mm), for ME with Lu-177 source (11.7, 11.5, and 11.6 mm), and for HE with I-131 (6.2, 13.1, and 13.1 mm) were obtained, and the system sensitivities were calculated as 89.9, 86.1, and 89.8 cps T /MBq with Tc-99m source; 42.7, 17.4, and 20.9 cps T /MBq with Lu-177 source; and 40.1, 69.7, and 77.4 cps T /MBq with I-131 source. The collimators of tungsten and tungsten alloy (97.0% W, 1.5% Fe, 1.5% Ni) provided better spatial resolution and improved image contrast when compared with conventional lead-based collimators. This was due to lower septal penetration. Conclusion The results suggest that development of a new set of ME and HE tungsten and tungsten alloy collimators could improve imaging of I-131, Lu-177, and I-123.
Collapse
Affiliation(s)
- Jalil Pirayesh Islamian
- Department of Medical Physics, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Michael Ljungberg
- Department of Medical Radiation Physics, Lund, Lund University, Lund, Sweden
| |
Collapse
|
2
|
Stokke C, Gnesin S, Tran-Gia J, Cicone F, Holm S, Cremonesi M, Blakkisrud J, Wendler T, Gillings N, Herrmann K, Mottaghy FM, Gear J. EANM guidance document: dosimetry for first-in-human studies and early phase clinical trials. Eur J Nucl Med Mol Imaging 2024; 51:1268-1286. [PMID: 38366197 PMCID: PMC10957710 DOI: 10.1007/s00259-024-06640-x] [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: 11/29/2023] [Accepted: 02/04/2024] [Indexed: 02/18/2024]
Abstract
The numbers of diagnostic and therapeutic nuclear medicine agents under investigation are rapidly increasing. Both novel emitters and novel carrier molecules require careful selection of measurement procedures. This document provides guidance relevant to dosimetry for first-in human and early phase clinical trials of such novel agents. The guideline includes a short introduction to different emitters and carrier molecules, followed by recommendations on the methods for activity measurement, pharmacokinetic analyses, as well as absorbed dose calculations and uncertainty analyses. The optimal use of preclinical information and studies involving diagnostic analogues is discussed. Good practice reporting is emphasised, and relevant dosimetry parameters and method descriptions to be included are listed. Three examples of first-in-human dosimetry studies, both for diagnostic tracers and radionuclide therapies, are given.
Collapse
Affiliation(s)
- Caroline Stokke
- Department of Diagnostic Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway.
- Department of Physics, University of Oslo, Oslo, Norway.
| | - Silvano Gnesin
- Institute of Radiation Physics, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Johannes Tran-Gia
- Department of Nuclear Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Francesco Cicone
- Nuclear Medicine Unit, Department of Experimental and Clinical Medicine, "Magna Graecia" University of Catanzaro, Catanzaro, Italy
| | - Søren Holm
- Department of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Marta Cremonesi
- Department of Medical Imaging and Radiation Sciences, European Institute of Oncology, IRCCS, Milan, Italy
| | - Johan Blakkisrud
- Department of Diagnostic Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway
| | - Thomas Wendler
- Computer-Aided Medical Procedures and Augmented Reality, Technische Universität München, Munich, Germany
- Clinical Computational Medical Imaging Research, Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Augsburg, Germany
| | - Nic Gillings
- Department of Clinical Physiology and Nuclear Medicine, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Ken Herrmann
- Department of Nuclear Medicine, University of Duisburg-Essen, and German Cancer Consortium (DKTK)-University Hospital Essen, Essen, Germany
- National Center for Tumor Diseases (NCT), NCT West, Heidelberg, Germany
| | - Felix M Mottaghy
- Department of Radiology and Nuclear Medicine, GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands
- Department of Nuclear Medicine, University Hospital RWTH Aachen, Aachen, Germany
| | - Jonathan Gear
- Joint Department of Physics, Royal Marsden NHSFT & Institute of Cancer Research, Sutton, UK
| |
Collapse
|
3
|
Budzyńska A, Kubik A, Kacperski K, Pastusiak P, Kuć M, Piasecki P, Konior M, Gryziński M, Dziuk M, Iller E. PET/CT and SPECT/CT imaging of 90Y hepatic radioembolization at therapeutic and diagnostic activity levels: Anthropomorphic phantom study. PLoS One 2024; 19:e0271711. [PMID: 38421965 PMCID: PMC10903856 DOI: 10.1371/journal.pone.0271711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 02/15/2024] [Indexed: 03/02/2024] Open
Abstract
PURPOSE Prior to 90Y radioembolization procedure, a pretherapy simulation using 99mTc-MAA is performed. Alternatively, a small dosage of 90Y microspheres could be used. We aimed to assess the accuracy of lung shunt fraction (LSF) estimation in both high activity 90Y posttreatment and pretreatment scans with isotope activity of ~100 MBq, using different imaging techniques. Additionally, we assessed the feasibility of visualising hot and cold hepatic tumours in PET/CT and Bremsstrahlung SPECT/CT images. MATERIALS AND METHODS Anthropomorphic phantom including liver (with two spherical tumours) and lung inserts was filled with 90Y chloride to simulate an LSF of 9.8%. The total initial activity in the liver was 1451 MBq, including 19.4 MBq in the hot sphere. Nine measurement sessions including PET/CT, SPECT/CT, and planar images were acquired at activities in the whole phantom ranging from 1618 MBq down to 43 MBq. The visibility of the tumours was appraised based on independent observers' scores. Quantitatively, contrast-to-noise ratio (CNR) was calculated for both spheres in all images. RESULTS LSF estimation. For high activity in the phantom, PET reconstructions slightly underestimated the LSF; absolute difference was <1.5pp (percent point). For activity <100 MBq, the LSF was overestimated. Both SPECT and planar scintigraphy overestimated the LSF for all activities. Lesion visibility. For SPECT/CT, the cold tumour proved too small to be discernible (CNR <0.5) regardless of the 90Y activity in the liver, while hot sphere was visible for activity >200 MBq (CNR>4). For PET/CT, the cold tumour was only visible with the highest 90Y activity (CNR>4), whereas the hot one was seen for activity >100 MBq (CNR>5). CONCLUSIONS PET/CT may accurately estimate the LSF in a 90Y posttreatment procedure. However, at low activities of about 100 MBq it seems to provide unreliable estimations. PET imaging provided better visualisation of both hot and cold tumours.
Collapse
Affiliation(s)
- Anna Budzyńska
- Department of Nuclear Medicine, Military Institute of Medicine - National Research Institute, Warsaw, Poland
- Affidea Mazovian PET-CT Medical Centre, Warsaw, Poland
| | - Agata Kubik
- Department of Nuclear Medicine, Military Institute of Medicine - National Research Institute, Warsaw, Poland
| | - Krzysztof Kacperski
- Department of Nuclear Medicine, Military Institute of Medicine - National Research Institute, Warsaw, Poland
- National Centre for Nuclear Research, Particle Acceleration Physics and Technology Division (TJ1), Otwock—Świerk, Poland
| | - Patrycja Pastusiak
- Department of Nuclear Medicine, Military Institute of Medicine - National Research Institute, Warsaw, Poland
| | - Michał Kuć
- National Centre for Nuclear Research, Radiological Metrology and Biomedical Physics Division (H2), Otwock—Świerk, Poland
| | - Piotr Piasecki
- Department of Interventional Radiology, Military Institute of Medicine - National Research Institute, Warsaw, Poland
| | - Marcin Konior
- National Centre for Nuclear Research, Radioisotope Centre POLATOM, Otwock - Świerk, Poland
| | - Michał Gryziński
- National Centre for Nuclear Research, Radiological Metrology and Biomedical Physics Division (H2), Otwock—Świerk, Poland
| | - Mirosław Dziuk
- Department of Nuclear Medicine, Military Institute of Medicine - National Research Institute, Warsaw, Poland
- Affidea Mazovian PET-CT Medical Centre, Warsaw, Poland
| | - Edward Iller
- National Centre for Nuclear Research, Radioisotope Centre POLATOM, Otwock - Świerk, Poland
| |
Collapse
|
4
|
Cicone F, Santo G, Bodet-Milin C, Cascini GL, Kraeber-Bodéré F, Stokke C, Kolstad A. Radioimmunotherapy of Non-Hodgkin B-cell Lymphoma: An update. Semin Nucl Med 2023; 53:413-425. [PMID: 36635112 DOI: 10.1053/j.semnuclmed.2022.12.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 12/23/2022] [Indexed: 01/12/2023]
Abstract
Systemic radioimmunotherapy (RIT) is arguably the most effective and least toxic anticancer treatment for non-Hodgkin lymphoma (NHL). In treatment-naïve patients with indolent NHL, the efficacy of a single injection of RIT compares with that of multiple cycles of combination chemotherapy. However, 20 years following the approval of the first CD20-targeting radioimmunoconjugates 90Y-Ibritumomab-tiuxetan (Zevalin) and 131I-tositumomab (Bexxar), the number of patients referred for RIT in western countries has dramatically decreased. Notwithstanding this, the development of RIT has continued. Therapeutic targets other than CD20 have been identified, new vector molecules have been produced allowing for faster delivery of RIT to the target, and innovative radionuclides with favorable physical characteristics such as alpha emitters have been more widely available. In this article, we reviewed the current status of RIT in NHL, with particular focus on recent clinical and preclinical developments.
Collapse
Affiliation(s)
- Francesco Cicone
- Department of Experimental and Clinical Medicine, "Magna Graecia" University of Catanzaro, Catanzaro, Italy; Nuclear Medicine Unit, University Hospital "Mater Domini", Catanzaro, Italy.
| | - Giulia Santo
- Department of Experimental and Clinical Medicine, "Magna Graecia" University of Catanzaro, Catanzaro, Italy
| | - Caroline Bodet-Milin
- Nuclear Medicine Department, Nantes Université, Univ Angers, CHU Nantes, INSERM, CNRS, CRCI2NA, F-44000 Nantes, France
| | - Giuseppe Lucio Cascini
- Department of Experimental and Clinical Medicine, "Magna Graecia" University of Catanzaro, Catanzaro, Italy; Nuclear Medicine Unit, University Hospital "Mater Domini", Catanzaro, Italy
| | - Françoise Kraeber-Bodéré
- Nuclear Medicine Department, Nantes Université, Univ Angers, CHU Nantes, INSERM, CNRS, CRCI2NA, F-44000 Nantes, France
| | - Caroline Stokke
- Division of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway; Department of Physics, University of Oslo, Oslo, Norway
| | - Arne Kolstad
- Department of Oncology, Innlandet Hospital Trust Division Gjøvik, Lillehammer, Norway
| |
Collapse
|
5
|
Chiesa C, Sjogreen-Gleisner K, Walrand S, Strigari L, Flux G, Gear J, Stokke C, Gabina PM, Bernhardt P, Konijnenberg M. EANM dosimetry committee series on standard operational procedures: a unified methodology for 99mTc-MAA pre- and 90Y peri-therapy dosimetry in liver radioembolization with 90Y microspheres. EJNMMI Phys 2021; 8:77. [PMID: 34767102 PMCID: PMC8589932 DOI: 10.1186/s40658-021-00394-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 06/21/2021] [Indexed: 11/27/2022] Open
Abstract
The aim of this standard operational procedure is to standardize the methodology employed for the evaluation of pre- and post-treatment absorbed dose calculations in 90Y microsphere liver radioembolization. Basic assumptions include the permanent trapping of microspheres, the local energy deposition method for voxel dosimetry, and the patient-relative calibration method for activity quantification.The identity of 99mTc albumin macro-aggregates (MAA) and 90Y microsphere biodistribution is also assumed. The large observed discrepancies in some patients between 99mTc-MAA predictions and actual 90Y microsphere distributions for lesions is discussed. Absorbed dose predictions to whole non-tumoural liver are considered more reliable and the basic predictors of toxicity. Treatment planning based on mean absorbed dose delivered to the whole non-tumoural liver is advised, except in super-selective treatments.Given the potential mismatch between MAA simulation and actual therapy, absorbed doses should be calculated both pre- and post-therapy. Distinct evaluation between target tumours and non-tumoural tissue, including lungs in cases of lung shunt, are vital for proper optimization of therapy. Dosimetry should be performed first according to a mean absorbed dose approach, with an optional, but important, voxel level evaluation. Fully corrected 99mTc-MAA Single Photon Emission Computed Tomography (SPECT)/computed tomography (CT) and 90Y TOF PET/CT are regarded as optimal acquisition methodologies, but, for institutes where SPECT/CT is not available, non-attenuation corrected 99mTc-MAA SPECT may be used. This offers better planning quality than non dosimetric methods such as Body Surface Area (BSA) or mono-compartmental dosimetry. Quantitative 90Y bremsstrahlung SPECT can be used if dedicated correction methods are available.The proposed methodology is feasible with standard camera software and a spreadsheet. Available commercial or free software can help facilitate the process and improve calculation time.
Collapse
Affiliation(s)
- Carlo Chiesa
- Nuclear Medicine Unit, Foundation IRCCS Istituto Nazionale Tumori, Milan, Italy
| | | | - Stephan Walrand
- Nuclear Medicine, Molecular Imaging, Radiotherapy and Oncology Unit (MIRO), IECR, Université Catholique de Louvain, Brussels, Belgium
| | - Lidia Strigari
- Medical Physics Division, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy
| | - Glenn Flux
- Joint Department of Physics, Royal Marsden Hospital & Institute of Cancer Research, Sutton, UK
| | - Jonathan Gear
- Joint Department of Physics, Royal Marsden Hospital & Institute of Cancer Research, Sutton, UK
| | - Caroline Stokke
- Department of Diagnostic Physics, Oslo University Hospital, Oslo, Norway
| | - Pablo Minguez Gabina
- Department of Medical Physics and Radiation Protection, Gurutzeta/Cruces University Hospital, Barakaldo, Spain
| | - Peter Bernhardt
- Department of Radiation Physics, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Mark Konijnenberg
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands.
| |
Collapse
|
6
|
Könik A, O'Donoghue JA, Wahl RL, Graham MM, Van den Abbeele AD. Theranostics: The Role of Quantitative Nuclear Medicine Imaging. Semin Radiat Oncol 2021; 31:28-36. [PMID: 33246633 DOI: 10.1016/j.semradonc.2020.07.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Theranostics is a precision medicine discipline that integrates diagnostic nuclear medicine imaging with radionuclide therapy in a manner that provides both a tumor phenotype and personalized therapy to patients with cancer using radiopharmaceuticals aimed at the same target-specific biological pathway or receptor. The aim of quantitative nuclear medicine imaging is to plan the alpha or beta-emitting therapy based on an accurate 3-dimensional representation of the in-vivo distribution of radioactivity concentration within the tumor and normal organs/tissues in a noninvasive manner. In general, imaging may be either based on positron emission tomography (PET) or single photon emission computed tomography (SPECT) invariably in combination with X-ray CT (PET/CT; SPECT/CT) or, to a much lesser extent, MRI. PET and SPECT differ in terms of the radionuclides and physical processes that give rise to the emission of high energy photons, as well as the sets of technologies involved in their detection. Using a variety of standardized quantitative parameters, system calibration, patient preparation, imaging acquisition and reconstruction protocols, and image analysis protocols, an accurate quantification of the tracer distribution can be obtained, which helps prescribe the therapeutic dose for each patient.
Collapse
Affiliation(s)
- Arda Könik
- Department of Imaging, Dana-Farber Cancer Institute, Boston, MA.
| | - Joseph A O'Donoghue
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Richard L Wahl
- Department of Radiology, Mallinckrodt Institute of Radiology, Washington University in St Louis School of Medicine, St. Louis, MO
| | - Michael M Graham
- Past Director of Nuclear Medicine, Roy J and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Annick D Van den Abbeele
- Department of Imaging, Dana-Farber Cancer Institute, Boston, MA; Division of Cancer Imaging, Mass General Brigham, Boston, MA; Dana-Farber Cancer Institute and Mass General Brigham, Boston, MA; Center for Biomedical Imaging in Oncology, Dana-Farber Cancer Institute, Boston, MA; Tumor Imaging Metrics Core, Dana-Farber/Harvard Cancer Center, Boston, MA
| |
Collapse
|
7
|
Hou X, Ma H, Esquinas PL, Uribe C, Tolhurst S, Bénard F, Liu D, Rahmim A, Celler A. Impact of image reconstruction method on dose distributions derived from 90Y PET images: phantom and liver radioembolization patient studies. Phys Med Biol 2020; 65:215022. [PMID: 33245057 DOI: 10.1088/1361-6560/aba8b5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
PET images acquired after liver 90Y radioembolization therapies are typically very noisy, which significantly challenges both visualization and quantification of activity distributions. To improve their noise characteristics, regularized iterative reconstruction algorithms such as block sequential regularized expectation maximization (Q.Clear for GE Healthcare, USA) have been proposed. In this study, we aimed to investigate the effects which different reconstruction algorithms may have on patient images, with reconstruction parameters initially narrowed down using phantom studies. Moreover, we evaluated the impact of these reconstruction methods on voxel-based dose distribution in phantom and patient studies (lesions and healthy livers). The International Electrotechnical Commission (IEC)/NEMA phantom, containing six spheres, was filled with 90Y and imaged using a GE Discovery 690 PET/CT scanner with time-of-flight enabled. The images were reconstructed using Q.Clear (with β parameter ranging from 0 to 8000) and ordered subsets expectation maximization. The image quality and quantification accuracy were evaluated by computing the hot ([Formula: see text]) and cold ([Formula: see text]) contrast recovery coefficients, background variability (BV) and activity bias. Next, dose distributions and dose volume histograms were generated using MIM® software's SurePlan LiverY90 toolbox. Subsequently, parameters optimized in these phantom studies were applied to five patient datasets. Dose parameters, such as Dmax, Dmean, D70, and V100Gy, were estimated, and their variability for different reconstruction methods was investigated. Based on phantom studies, the β parameter values optimized for image quality and quantification accuracy were 2500 and 300, respectively. When all investigated reconstructions were applied to patient studies, Dmean, D50, D70, and V100Gy showed coefficients of variation below 8%; whereas the variability of Dmax was up to 30% for both phantom and patient images. Although β = 300-1000 would provide accurate activity quantification for a region of interest, when considering activity/dose voxelized distribution, higher β value (e.g. 4000-5000) would provide the greatest accuracy for dose distributions. In this 90Y radioembolization PET/CT study, the β parameter in regularized iterative (Q.Clear) reconstruction was investigated for image quality, accurate quantification and dose distributions based on phantom experiments and then applied to patient studies. Our results indicate that more accurate dose distribution can be achieved from smoother PET images, reconstructed with larger β values than those yielding the best activity quantifications but noisy images. Most importantly, these results suggest that quantitative measures, which are commonly used in clinics, such as SUVmax or SUVpeak( equivalent of Dmax), should not be employed for 90Y PET images, since their values would highly depend on the image reconstruction.
Collapse
Affiliation(s)
- Xinchi Hou
- Department of Radiology, University of British Columbia, Vancouver, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Nakanishi K, Yamamoto S. Monte Carlo simulation of the bremsstrahlung X-rays emitted from H-3 and C-14 for the in-vivo imaging of small animals. Appl Radiat Isot 2020; 160:109136. [PMID: 32351228 DOI: 10.1016/j.apradiso.2020.109136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 01/22/2020] [Accepted: 03/17/2020] [Indexed: 01/31/2023]
Abstract
For the imaging using low energy pure beta-emitting radionuclides, autoradiography is used by slicing the subjects because the range of beta particles is short and thought to be impossible to detect beta particles from outside the subjects. Contrary to this scientific consensus, we recently found that the distributions of C-14 could be measured by detecting the bremsstrahlung X-rays emitted from the solution of C-14 and may also be applicable to lower energy pure beta-emitting radionuclide, H-3. Although the detection of bremsstrahlung X-rays emitted from H-3 and C-14 may be a possible method for in-vivo imaging of small animals, the absorption of the bremsstrahlung X-rays in the subjects are significant because the energy of bremsstrahlung X-rays is relatively low. In addition, the generations of bremsstrahlung X-rays are lower for low energy beta particles. They may make the in-vivo imaging of these beta radionuclides difficult. To clarify these points for the in-vivo imaging of bremsstrahlung X-rays emitted from H-3 and C-14, we used Monte Carlo simulation to calculate the numbers of counts and the energy spectra of the bremsstrahlung X-rays emitted from H-3 and C-14 in water. The simulation results showed that the fraction of detected bremsstrahlung X-rays by a 4 cm × 4 cm detector in all emitted beta particles was 3.5 × 10-6 at 0.1 mm from the source. Thus, with a 10 M Bq of H-3, we will detect ~35 cps at 0.1 mm from the source so in-vivo imaging at surface area will be possible. For C-14, the fraction of detected bremsstrahlung X-rays by the detector without and with collimator were 7.0 × 10-5 and 1.1 × 10-6 at 10 mm from the source, respectively. Thus, with a 10 M Bq of C-14, we will detect ~700 cps and ~11 cps at 10 mm from the source without and with collimator, respectively. The count rate without collimator is easy to form an image in a short time using a low energy X-ray detector. With collimator, in-vivo imaging of distribution of C-14 will be possible. We conclude that in-vivo imaging of small animals by detecting the bremsstrahlung X-rays emitted from H-3 and C-14 is possible and promising for a new molecular imaging technology.
Collapse
Affiliation(s)
- Kouhei Nakanishi
- Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan; Department of Radiology, Akita Hospital, Chiryu, Japan.
| | - Seiichi Yamamoto
- Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan.
| |
Collapse
|
9
|
Ermert J, Benešová M, Hugenberg V, Gupta V, Spahn I, Pietzsch HJ, Liolios C, Kopka K. Radiopharmaceutical Sciences. Clin Nucl Med 2020. [DOI: 10.1007/978-3-030-39457-8_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
10
|
Seo Y. Quantitative Imaging of Alpha-Emitting Therapeutic Radiopharmaceuticals. Nucl Med Mol Imaging 2019; 53:182-188. [PMID: 31231438 DOI: 10.1007/s13139-019-00589-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 02/02/2019] [Accepted: 02/07/2019] [Indexed: 11/24/2022] Open
Abstract
Targeted alpha therapy (TAT) is an active area of drug development as a highly specific and highly potent therapeutic modality that can be applied to many types of late-stage cancers. In order to properly evaluate its safety and efficacy, understanding biokinetics of alpha-emitting radiopharmaceuticals is essential. Quantitative imaging of alpha-emitting radiopharmaceuticals is often possible via imaging of gammas and positrons produced during complex decay chains of these radionuclides. Analysis of the complex decay chains for alpha-emitting radionuclides (Tb-149, At-211, Bi-212 (decayed from Pb-212), Bi-213, Ra-223, Ac-225, and Th-227) with relevance to imageable signals is attempted in this mini-review article. Gamma camera imaging, single-photon emission computed tomography, positron emission tomography, bremsstrahlung radiation imaging, Cerenkov luminescence imaging, and Compton cameras are briefly discussed as modalities for imaging alpha-emitting radiopharmaceuticals.
Collapse
Affiliation(s)
- Youngho Seo
- 1Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA USA
- 2Department of Radiation Oncology, University of California, San Francisco, CA USA
- 3Bakar Computational Health Sciences Institute, University of California, San Francisco, CA USA
- UC Berkeley - UCSF Bioengineering Graduate Program, Berkeley and San Francisco, CA USA
- 5Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA USA
- 6UCSF Physics Research Laboratory, 185 Berry Street, Suite 350, San Francisco, CA 94143-0946 USA
| |
Collapse
|
11
|
Effects of collimator on imaging performance of Yttrium-90 Bremsstrahlung photons: Monte Carlo simulation. NUCLEAR ENGINEERING AND TECHNOLOGY 2019. [DOI: 10.1016/j.net.2018.11.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
12
|
Ljungberg M, Sjogreen Gleisner K. 3-D Image-Based Dosimetry in Radionuclide Therapy. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2018. [DOI: 10.1109/trpms.2018.2860563] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
13
|
Morschhauser F, Dekyndt B, Baillet C, Barthélémy C, Malek E, Fulcrand J, Bigot P, Huglo D, Décaudin B, Simon N, Odou P. A new pharmacokinetic model for 90Y-ibritumomab tiuxetan based on 3-dimensional dosimetry. Sci Rep 2018; 8:14860. [PMID: 30291297 PMCID: PMC6173718 DOI: 10.1038/s41598-018-33160-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 09/07/2018] [Indexed: 02/01/2023] Open
Abstract
Monoclonal antibodies (mAbs) are key components in several therapies for cancer and inflammatory diseases but current knowledge of their clinical pharmacokinetics and distribution in human tissues remains incomplete. Consequently, optimal dosing and scheduling in clinics are affected. With sequential radiolabeled mAb-based imaging, radiation dosing in tissues/organs can be calculated to provide a better assessment of mAb concentrations in tissues. This is the first pharmacokinetic model of 90Y-Ibritumomab tiuxetan (90Y-IT) in humans to be described, based on three-dimensional (3D) dosimetry using single-photon emission computed-tomography coupled with computed-tomography. 19 patients with follicular lymphoma were treated initially with 90Y-IT in the FIZZ trial. Based on a compartmental approach individualising the vascular compartment within studied organs, this study proposes a reliable pharmacokinetic (PK) five-compartment model replacing the currently used two-compartment model and constitutes a new direction for further research. This model provides exchange constants between the different tissues, Area Under the Curve of 111In-IT in blood (AUC) and Mean Residence Time (MRT) that have not been reported so far for IT. Finally, the elimination process appears to occur in a compartment other than the liver or the spleen and suggests the metabolism of mAbs may take place mainly on the vascular compartment level.
Collapse
Affiliation(s)
- F Morschhauser
- Univ. Lille, CHU Lille, EA 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associees, Lille, France. .,Haematology Department, Hôpital Claude Huriez, CHU Lille, F-59000, Lille, France.
| | - B Dekyndt
- Univ. Lille, CHU Lille, EA 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associees, Lille, France.,Pharmacy Institute, CHU Lille, F-59000, Lille, France
| | - C Baillet
- Univ. Lille, CHU Lille, EA 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associees, Lille, France.,Nuclear Medicine department, Hôpital Claude Huriez, CHU Lille, F-59000, Lille, France
| | - C Barthélémy
- Univ. Lille, CHU Lille, EA 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associees, Lille, France
| | - E Malek
- Univ. Lille, CHU Lille, EA 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associees, Lille, France
| | - J Fulcrand
- Univ. Lille, CHU Lille, EA 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associees, Lille, France
| | - P Bigot
- Univ. Lille, CHU Lille, EA 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associees, Lille, France
| | - D Huglo
- Nuclear Medicine department, Hôpital Claude Huriez, CHU Lille, F-59000, Lille, France
| | - B Décaudin
- Univ. Lille, CHU Lille, EA 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associees, Lille, France.,Pharmacy Institute, CHU Lille, F-59000, Lille, France
| | - N Simon
- Univ. Lille, CHU Lille, EA 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associees, Lille, France.,Pharmacy Institute, CHU Lille, F-59000, Lille, France
| | - P Odou
- Univ. Lille, CHU Lille, EA 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associees, Lille, France.,Pharmacy Institute, CHU Lille, F-59000, Lille, France
| |
Collapse
|
14
|
Lim H, Fessler JA, Wilderman SJ, Brooks AF, Dewaraja YK. Y-90 SPECT ML image reconstruction with a new model for tissue-dependent bremsstrahlung production using CT information: a proof-of-concept study. Phys Med Biol 2018; 63:115001. [PMID: 29714716 PMCID: PMC6112241 DOI: 10.1088/1361-6560/aac1ad] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
While the yield of positrons used in Y-90 PET is independent of tissue media, Y-90 SPECT imaging is complicated by the tissue dependence of bremsstrahlung photon generation. The probability of bremsstrahlung production is proportional to the square of the atomic number of the medium. Hence, the same amount of activity in different tissue regions of the body will produce different numbers of bremsstrahlung photons. Existing reconstruction methods disregard this tissue-dependency, potentially impacting both qualitative and quantitative imaging of heterogeneous regions of the body such as bone with marrow cavities. In this proof-of-concept study, we propose a new maximum-likelihood method that incorporates bremsstrahlung generation probabilities into the system matrix, enabling images of the desired Y-90 distribution to be reconstructed instead of the 'bremsstrahlung distribution' that is obtained with existing methods. The tissue-dependent probabilities are generated by Monte Carlo simulation while bone volume fractions for each SPECT voxel are obtained from co-registered CT. First, we demonstrate the tissue dependency in a SPECT/CT imaging experiment with Y-90 in bone equivalent solution and water. Visually, the proposed reconstruction approach better matched the true image and the Y-90 PET image than the standard bremsstrahlung reconstruction approach. An XCAT phantom simulation including bone and marrow regions also demonstrated better agreement with the true image using the proposed reconstruction method. Quantitatively, compared with the standard reconstruction, the new method improved estimation of the liquid bone:water activity concentration ratio by 40% in the SPECT measurement and the cortical bone:marrow activity concentration ratio by 58% in the XCAT simulation.
Collapse
Affiliation(s)
- Hongki Lim
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI 48109, United States of America
| | | | | | | | | |
Collapse
|
15
|
Yue J, Mauxion T, Reyes DK, Lodge MA, Hobbs RF, Rong X, Dong Y, Herman JM, Wahl RL, Geschwind JFH, Frey EC. Comparison of quantitative Y-90 SPECT and non-time-of-flight PET imaging in post-therapy radioembolization of liver cancer. Med Phys 2017; 43:5779. [PMID: 27782730 DOI: 10.1118/1.4962472] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Radioembolization with yttrium-90 microspheres may be optimized with patient-specific pretherapy treatment planning. Dose verification and validation of treatment planning methods require quantitative imaging of the post-therapy distribution of yttrium-90 (Y-90). Methods for quantitative imaging of Y-90 using both bremsstrahlung SPECT and PET have previously been described. The purpose of this study was to compare the two modalities quantitatively in humans. METHODS Calibration correction factors for both quantitative Y-90 bremsstrahlung SPECT and a non-time-of-flight PET system without compensation for prompt coincidences were developed by imaging three phantoms. The consistency of these calibration correction factors for the different phantoms was evaluated. Post-therapy images from both modalities were obtained from 15 patients with hepatocellular carcinoma who underwent hepatic radioembolization using Y-90 glass microspheres. Quantitative SPECT and PET images were rigidly registered and the total liver activities and activity distributions estimated for each modality were compared. The activity distributions were compared using profiles, voxel-by-voxel correlation and Bland-Altman analyses, and activity-volume histograms. RESULTS The mean ± standard deviation of difference in the total activity in the liver between the two modalities was 0% ± 9% (range -21%-18%). Voxel-by-voxel comparisons showed a good agreement in regions corresponding roughly to treated tumor and treated normal liver; the agreement was poorer in regions with low or no expected activity, where PET appeared to overestimate the activity. The correlation coefficients between intrahepatic voxel pairs for the two modalities ranged from 0.86 to 0.94. Cumulative activity volume histograms were in good agreement. CONCLUSIONS These data indicate that, with appropriate reconstruction methods and measured calibration correction factors, either Y-90 SPECT/CT or Y-90 PET/CT can be used for quantitative post-therapy monitoring of Y-90 activity distribution following hepatic radioembolization.
Collapse
Affiliation(s)
- Jianting Yue
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland 21287
| | - Thibault Mauxion
- Biocompatibles UK Ltd, A BTG Group Company, Camberley, GU15 3YL, United Kingdom
| | - Diane K Reyes
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland 21287
| | - Martin A Lodge
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland 21287
| | - Robert F Hobbs
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland 21287 and Department of Radiation Oncology, Johns Hopkins University, Baltimore, Maryland 21287
| | - Xing Rong
- Siemens Medical Solutions USA Inc., Hoffman Estates, Illinois 60192
| | - Yinfeng Dong
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland 21287
| | - Joseph M Herman
- Department of Radiation Oncology, Johns Hopkins University, Baltimore, Maryland 21287
| | - Richard L Wahl
- Department of Diagnostic Radiology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri 06310
| | | | - Eric C Frey
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, Maryland 21287
| |
Collapse
|
16
|
Personalized Dosimetry for Radionuclide Therapy Using Molecular Imaging Tools. Biomedicines 2016; 4:biomedicines4040025. [PMID: 28536392 PMCID: PMC5344265 DOI: 10.3390/biomedicines4040025] [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] [Received: 09/12/2016] [Revised: 11/07/2016] [Accepted: 11/08/2016] [Indexed: 11/16/2022] Open
Abstract
For treatment of systemic malignancies, when external radiation therapy is not applicable, radionuclide therapy can be an alternative. In this form of therapy, radionuclides are administered to the patient, often in a form where the radionuclide is labelled to a molecule that plays the active part in the localization of the tumor. Since the aim is to impart lethal damage to tumor cells while maintaining possible side-effects to normal tissues at tolerable levels, a proper and accurate personalized dosimetry should be a pre-requisite. In radionuclide therapy, there is a need to measure the distribution of the radiopharmaceutical in vivo, as well as its re-distribution over time, in order estimate the total energy released in radioactive decays and subsequent charged-particle interactions, governing the absorbed dose to different organs and tumors. Measurements are usually performed by molecular imaging, more specifically planar and SPECT (Single-Photon Emission Computed Tomography) imaging, combined with CT. This review describes the different parts in the dosimetry chain of radionuclide therapy. Emphasis is given to molecular imaging tools and the requirements for determining absorbed doses from quantitative planar and SPECT images. As example solutions to the different problems that need to be addressed in such a dosimetric chain, we describe our tool, Lundadose, which is a set of methods that we have developed for personalized dosimetry.
Collapse
|
17
|
Evans-Axelsson S, Timmermand OV, Bjartell A, Strand SE, Elgqvist J. Radioimmunotherapy for Prostate Cancer--Current Status and Future Possibilities. Semin Nucl Med 2016; 46:165-79. [PMID: 26897720 DOI: 10.1053/j.semnuclmed.2015.10.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Prostate cancer (PCa) is one of the most common cancers in men and is the second leading cause of cancer-related deaths in the USA. In the United States, it is the second most frequently diagnosed cancer after skin cancer, and in Europe it is number one. According to the American Cancer Society, approximately 221,000 men in the United States would be diagnosed with PCa during 2015, and approximately 28,000 would die of the disease. According to the International Agency for Research on Cancer, approximately 345,000 men were diagnosed with PCa in Europe during 2012, and despite more emphasis placed on early detection through routine screening, 72,000 men died of the disease. Hence, the need for improved therapy modalities is of utmost importance. And targeted therapies based on radiolabeled specific antibodies or peptides are a very interesting and promising alternative to increase the therapeutic efficacy and overall chance of survival of these patients. There are currently several preclinical and some clinical studies that have been conducted, or are ongoing, to investigate the therapeutic efficacy and toxicity of radioimmunotherapy (RIT) against PCa. One thing that is lacking in a lot of these published studies is the dosimetry data, which are needed to compare results between the studies and the study locations. Given the complicated tumor microenvironment and overall complexity of RIT to PCa, old and new targets and targeting strategies like combination RIT and pretargeting RIT are being improved and assessed along with various therapeutic radionuclides candidates. Given alone or in combination with other therapies, these new and improved strategies and RIT tools further enhance the clinical response to RIT drugs in PCa, making RIT for PCa an increasingly practical clinical tool.
Collapse
Affiliation(s)
- Susan Evans-Axelsson
- Department of Translational Medicine, Division of Urological Cancers, Skåne University Hospital, Malmö, Lund University, Lund, Sweden
| | | | - Anders Bjartell
- Department of Translational Medicine, Division of Urological Cancers, Skåne University Hospital, Malmö, Lund University, Lund, Sweden; Department of Urology, Skåne University Hospital, Malmö, Sweden
| | - Sven-Erik Strand
- Department of Clinical Sciences, Lund, Division of Medical Radiation Physics, Lund University, Lund, Sweden
| | - Jörgen Elgqvist
- Department of Clinical Sciences, Lund, Division of Medical Radiation Physics, Lund University, Lund, Sweden.
| |
Collapse
|
18
|
Analysis of the influence of 111In on 90Y-bremsstrahlung SPECT based on Monte Carlo simulation. Ann Nucl Med 2016; 30:675-681. [PMID: 27510893 DOI: 10.1007/s12149-016-1112-9] [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] [Received: 03/28/2016] [Accepted: 08/01/2016] [Indexed: 10/21/2022]
Abstract
OBJECTIVE 90Y-ibritumomab tiuxetan (Zevalin) which is used for the treatment of malignant lymphomas can be used for SPECT imaging based on bremsstrahlung from 90Y beta particles. However, gamma rays emitted by 111In, which is administered to evaluate the indication for the treatment, contaminate the 90Y bremsstrahlung images. Our objective is to investigate the influence of 111In on the 90Y SPECT images using Monte Carlo simulation. METHODS We used an in-house developed simulation code for the Monte Carlo simulation of electrons and photons (MCEP). Two hot spheres with diameters of 40 mm were put in an elliptical phantom. Both spheres ("sphere 1" and "sphere 2") were filled with 90Y and 111In mixed solutions. The activities of 90Y in sphere 1 and sphere 2 were 241 and 394 kBq/mL, respectively, and the ones of 111In were 8.14 and 13.3 kBq/mL, respectively. The background activity of 90Y was 38.6 kBq/mL, whereas that of 111In was 1.30 kBq/mL; moreover, the acquisition time was 30 min. Two energy windows were used: one is 90-190 keV included the 111In photopeak; the other is 90-160 keV. To evaluate the quality of the SPECT images, the contrast recovery coefficient (CRC) and the constant noise ratio (CNR) of the SPECT images were derived. RESULTS For the energy window between 90 and 160 keV, the 111In count was 74 % of the total. In that case, the CRC values were 30.1 and 30.7 % for "sphere 1" and "sphere 2", respectively, whereas the CNR values were 6.8 and 12.1, respectively. For the energy window between 90 and 190 keV, the 111In count reached 85 % of the total count. The CRC and CNR values were 38.6 and 40.0 % and 10.6 and 19.4, respectively. CONCLUSIONS Our simulation study revealed that the cross talk between 111In and 90Y in SPECT imaging is rather serious. Even for the energy window excluding the 111In photopeak, the count ratio of 90Y was less than 30 % of the total. However, the influence of 111In on 90Y-SPECT imaging cannot be ignored, and the count ratio because of 111In is important to estimate the density of 90Y.
Collapse
|
19
|
Theranostic Imaging of Yttrium-90. BIOMED RESEARCH INTERNATIONAL 2015; 2015:481279. [PMID: 26106608 PMCID: PMC4464848 DOI: 10.1155/2015/481279] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Accepted: 04/22/2015] [Indexed: 01/07/2023]
Abstract
This paper overviews Yttrium-90 ((90)Y) as a theranostic and nuclear medicine imaging of (90)Y radioactivity with bremsstrahlung imaging and positron emission tomography. In addition, detection and optical imaging of (90)Y radioactivity using Cerenkov luminescence will also be reviewed. Methods and approaches for qualitative and quantitative (90)Y imaging will be briefly discussed. Although challenges remain for (90)Y imaging, continued clinical demand for predictive imaging response assessment and target/nontarget dosimetry will drive research and technical innovation to provide greater clinical utility of (90)Y as a theranostic agent.
Collapse
|
20
|
Physiologically Based Pharmacokinetic Modeling Is Essential in 90Y-Labeled Anti-CD66 Radioimmunotherapy. PLoS One 2015; 10:e0127934. [PMID: 26010360 PMCID: PMC4444288 DOI: 10.1371/journal.pone.0127934] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 04/20/2015] [Indexed: 12/21/2022] Open
Abstract
Introduction Radioimmunotherapy (RIT) with 90Y-labeled anti-CD66 antibody is used to selectively irradiate the red marrow (RM) before blood stem cell transplantation of acute leukemia patients. To calculate the activity to administer, time-integrated activity coefficients are required. These are estimated prior to therapy using gamma camera and serum measurements after injection of 111In labeled anti-CD66 antibody. Equal pre-therapeutic and therapeutic biodistributions are usually assumed to calculate the coefficients. However, additional measurements during therapy had shown that this assumption had to be abandoned. A physiologically based pharmacokinetic (PBPK) model was developed to allow the prediction of therapeutic time-integrated activity coefficients in eight patients. Aims The aims of the study were to demonstrate using a larger patient group 1) the need to perform patient-specific dosimetry in 90Y-labeled anti-CD66 RIT, 2) that pre-therapeutic and therapeutic biodistributions differ, and most importantly 3) that this difference in biodistributions can be accurately predicted using a refined model. Materials and Methods Two new PBPK models were developed considering fully, half and non-immunoreactive antibodies and constraints for estimating the RM antigen number. Both models were fitted to gamma camera and serum measurements of 27 patients. Akaike weights were used for model averaging. Time-integrated activity coefficients for total body, liver, spleen, RM and serum were calculated. Model-based predictions of the serum biokinetics during therapy were compared to actual measurements. Results Variability of the RM time-integrated activity coefficients ((37.3±7.5) h) indicates the need for patient-specific dosimetry. The relative differences between pre-therapeutic and therapeutic serum time-activity curves were (-25±16)%. The prediction accuracy of these differences using the refined PBPK models was (-3±20)%. Conclusion Individual treatment is needed due to biological differences between patients in RIT with 90Y-labeled anti-CD66 antibody. Differences in pre-therapeutic and therapeutic biokinetics are predominantly caused by different degrees of saturation due to different amounts of administered antibody. These differences could be predicted using the PBPK models.
Collapse
|
21
|
Lohrmann C, Zhang H, Thorek DLJ, Desai P, Zanzonico PB, O'Donoghue J, Irwin CP, Reiner T, Grimm J, Weber WA. Cerenkov Luminescence Imaging for Radiation Dose Calculation of a ⁹⁰Y-Labeled Gastrin-Releasing Peptide Receptor Antagonist. J Nucl Med 2015; 56:805-11. [PMID: 25840974 DOI: 10.2967/jnumed.114.149054] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 02/27/2015] [Indexed: 12/15/2022] Open
Abstract
UNLABELLED (90)Y has been used to label various new therapeutic radiopharmaceuticals. However, measuring the radiation dose delivered by (90)Y is challenging because of the absence of suitable γ emissions and its low abundance of positron emissions. For the treatment of prostate cancer, radiolabeled gastrin-releasing peptide receptor (GRPr) antagonists have yielded promising results in mouse models. In this study, we evaluated whether Cerenkov luminescence imaging (CLI) could be used to determine radiation doses of a (90)Y-labeled GRPr antagonist in nude mice. METHODS Mice bearing subcutaneous prostate cancer xenografts were injected with 0.74-18.5 MBq of the (90)Y-labeled GRPr antagonist DOTA-AR and underwent in vivo and ex vivo CLI at 1-48 h after injection. After imaging, animals were sacrificed, their tumors and organs were harvested, and the activity concentration was measured by liquid scintillation counting. In a second set of experiments, Cerenkov photon counts for tumor and kidney on in vivo CLI were converted to activity concentrations using conversion factors determined from the first set of experiments. RESULTS (90)Y-DOTA-AR concentration in the 3 tumor models ranged from 0.5% to 4.8% of the injected activity per gram at 1 h after injection and decreased to 0.05%-0.15 injected activity per gram by 48 h after injection. A positive correlation was found between tumor activity concentrations and in vivo CLI signal (r(2) = 0.94). A similar correlation was found for the renal activity concentration and in vivo Cerenkov luminescence (r(2) = 0.98). Other organs were not distinctly visualized on the in vivo images, but ex vivo CLI was also correlated with the radioactivity concentration (r(2) = 0.35-0.94). Using the time-activity curves from the second experiment, we calculated radiation doses to tumor and kidney of 0.33 ± 0.12 (range, 0.21-0.66) and 0.06 ± 0.01 (range, 0.05-0.08) Gy/MBq, respectively. CONCLUSION CLI is a promising, low-cost modality to measure individual radiation doses of (90)Y-labeled compounds noninvasively. The use of Cerenkov imaging is expected to facilitate the development and comparison of (90)Y-labeled compounds for targeted radiotherapy.
Collapse
Affiliation(s)
- Christian Lohrmann
- Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Hanwen Zhang
- Radiochemistry and Imaging Sciences Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Daniel L J Thorek
- Division of Nuclear Medicine, Department of Radiology, Johns Hopkins Medicine, Baltimore, Maryland
| | - Pooja Desai
- Radiochemistry and Imaging Sciences Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Pat B Zanzonico
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York; and
| | - Joseph O'Donoghue
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York; and
| | - Christopher P Irwin
- Radiochemistry and Imaging Sciences Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Thomas Reiner
- Radiochemistry and Imaging Sciences Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Jan Grimm
- Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Wolfgang A Weber
- Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, New York, New York
| |
Collapse
|
22
|
Chalkia MT, Stefanoyiannis AP, Chatziioannou SN, Round WH, Efstathopoulos EP, Nikiforidis GC. Patient-specific dosimetry in peptide receptor radionuclide therapy: a clinical review. AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2014; 38:7-22. [PMID: 25427548 DOI: 10.1007/s13246-014-0312-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 11/06/2014] [Indexed: 12/16/2022]
Abstract
Neuroendocrine tumours (NETs) belong to a relatively rare class of neoplasms. Nonetheless, their prevalence has increased significantly during the last decades. Peptide receptor radionuclide therapy (PRRT) is a relatively new treatment approach for inoperable or metastasised NETs. The therapeutic effect is based on the binding of radiolabelled somatostatin analogue peptides with NETs' somatostatin receptors, resulting in internal irradiation of tumours. Pre-therapeutic patient-specific dosimetry is essential to ensure that a treatment course has high levels of safety and efficacy. This paper reviews the methods applied for PRRT dosimetry, as well as the dosimetric results presented in the literature. Focus is given on data concerning the therapeutic somatostatin analogue radiopeptides (111)In-[DTPA(0),D-Phe(1)]-octreotide ((111)In-DTPA-octreotide), (90)Y-[DOTA(0),Tyr(3)]-octreotide ((90)Y-DOTATOC) and (177)Lu-[DOTA(0),Tyr(3),Thr(8)]-octreotide ((177)Lu-DOTATATE). Following the Medical Internal Radiation Dose (MIRD) Committee formalism, dosimetric analysis demonstrates large interpatient variability in tumour and organ uptake, with kidneys and bone marrow being the critical organs. The results are dependent on the image acquisition and processing protocol, as well as the dosimetric imaging radiopharmaceutical.
Collapse
Affiliation(s)
- M T Chalkia
- University General Hospital of Athens "Attikon", 1, Rimini Street, Chaidari, 12462, Athens, Greece
| | | | | | | | | | | |
Collapse
|
23
|
Attarwala AA, Molina-Duran F, Büsing KA, Schönberg SO, Bailey DL, Willowson K, Glatting G. Quantitative and qualitative assessment of Yttrium-90 PET/CT imaging. PLoS One 2014; 9:e110401. [PMID: 25369020 PMCID: PMC4219690 DOI: 10.1371/journal.pone.0110401] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 09/22/2014] [Indexed: 11/24/2022] Open
Abstract
Yttrium-90 is known to have a low positron emission decay of 32 ppm that may allow for personalized dosimetry of liver cancer therapy with 90Y labeled microspheres. The aim of this work was to image and quantify 90Y so that accurate predictions of the absorbed dose can be made. The measurements were performed within the QUEST study (University of Sydney, and Sirtex Medical, Australia). A NEMA IEC body phantom containing 6 fillable spheres (10–37 mm ∅) was used to measure the 90Y distribution with a Biograph mCT PET/CT (Siemens, Erlangen, Germany) with time-of-flight (TOF) acquisition. A sphere to background ratio of 8∶1, with a total 90Y activity of 3 GBq was used. Measurements were performed for one week (0, 3, 5 and 7 d). he acquisition protocol consisted of 30 min-2 bed positions and 120 min-single bed position. mages were reconstructed with 3D ordered subset expectation maximization (OSEM) and point spread function (PSF) for iteration numbers of 1–12 with 21 (TOF) and 24 (non-TOF) subsets and CT based attenuation and scatter correction. Convergence of algorithms and activity recovery was assessed based on regions-of-interest (ROI) analysis of the background (100 voxels), spheres (4 voxels) and the central low density insert (25 voxels). For the largest sphere, the recovery coefficient (RC) values for the 30 min –2-bed position, 30 min-single bed and 120 min-single bed were 1.12±0.20, 1.14±0.13, 0.97±0.07 respectively. For the smaller diameter spheres, the PSF algorithm with TOF and single bed acquisition provided a comparatively better activity recovery. Quantification of Y-90 using Biograph mCT PET/CT is possible with a reasonable accuracy, the limitations being the size of the lesion and the activity concentration present. At this stage, based on our study, it seems advantageous to use different protocols depending on the size of the lesion.
Collapse
Affiliation(s)
- Ali Asgar Attarwala
- Medical Radiation Physics/Radiation Protection, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Flavia Molina-Duran
- Medical Radiation Physics/Radiation Protection, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Karen-Anett Büsing
- Institute of Clinical Radiology and Nuclear Medicine, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Stefan O. Schönberg
- Institute of Clinical Radiology and Nuclear Medicine, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Dale L. Bailey
- Department of Nuclear Medicine, Royal North Shore Hospital, Sydney, Australia
| | - Kathy Willowson
- Institute of Medical Physics, School of Physics, University of Sydney, Sydney, NSW, Australia
| | - Gerhard Glatting
- Medical Radiation Physics/Radiation Protection, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- * E-mail:
| |
Collapse
|
24
|
Ahangari HT, Rajabi H, Eftekhari M, Daha FJ, Mansoury MAT. Liver Bremsstrahlung Imaging with Pure Beta Emitter. JOURNAL OF MEDICAL SCIENCES 2014. [DOI: 10.3923/jms.2014.210.216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
25
|
Walrand S, Hesse M, Wojcik R, Lhommel R, Jamar F. Optimal design of anger camera for bremsstrahlung imaging: monte carlo evaluation. Front Oncol 2014; 4:149. [PMID: 24982849 PMCID: PMC4056384 DOI: 10.3389/fonc.2014.00149] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 05/29/2014] [Indexed: 11/29/2022] Open
Abstract
A conventional Anger camera is not adapted to bremsstrahlung imaging and, as a result, even using a reduced energy acquisition window, geometric x-rays represent <15% of the recorded events. This increases noise, limits the contrast, and reduces the quantification accuracy. Monte Carlo (MC) simulations of energy spectra showed that a camera based on a 30-mm-thick BGO crystal and equipped with a high energy pinhole collimator is well-adapted to bremsstrahlung imaging. The total scatter contamination is reduced by a factor 10 versus a conventional NaI camera equipped with a high energy parallel hole collimator enabling acquisition using an extended energy window ranging from 50 to 350 keV. By using the recorded event energy in the reconstruction method, shorter acquisition time and reduced orbit range will be usable allowing the design of a simplified mobile gantry. This is more convenient for use in a busy catheterization room. After injecting a safe activity, a fast single photon emission computed tomography could be performed without moving the catheter tip in order to assess the liver dosimetry and estimate the additional safe activity that could still be injected. Further long running time MC simulations of realistic acquisitions will allow assessing the quantification capability of such system. Simultaneously, a dedicated bremsstrahlung prototype camera reusing PMT–BGO blocks coming from a retired PET system is currently under design for further evaluation.
Collapse
Affiliation(s)
- Stephan Walrand
- Department of Nuclear Medicine, Molecular Imaging, Radiotherapy and Oncology Unit (MIRO), IECR, Université Catholique de Louvain , Brussels , Belgium
| | - Michel Hesse
- Department of Nuclear Medicine, Molecular Imaging, Radiotherapy and Oncology Unit (MIRO), IECR, Université Catholique de Louvain , Brussels , Belgium
| | | | - Renaud Lhommel
- Department of Nuclear Medicine, Molecular Imaging, Radiotherapy and Oncology Unit (MIRO), IECR, Université Catholique de Louvain , Brussels , Belgium
| | - François Jamar
- Department of Nuclear Medicine, Molecular Imaging, Radiotherapy and Oncology Unit (MIRO), IECR, Université Catholique de Louvain , Brussels , Belgium
| |
Collapse
|
26
|
Technical Considerations of Phosphorous-32 Bremsstrahlung SPECT Imaging after Radioembolization of Hepatic Tumors: A Clinical Assessment with a Review of Imaging Parameters. Radiol Res Pract 2014; 2014:407158. [PMID: 24800073 PMCID: PMC3985385 DOI: 10.1155/2014/407158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 02/15/2014] [Accepted: 02/19/2014] [Indexed: 12/12/2022] Open
Abstract
Background. Bremsstrahlung (BS) imaging during radioembolization (RE) confirms the deposition of radiotracer in hepatic/extrahepatic tumors. The aim of this study is to demonstrate (32)P images and to optimize the imaging parameters. Materials and Methods. Thirty-nine patients with variable types of hepatic tumors, treated with the intra-arterial injection of (32)P, were included. All patients underwent BS SPECT imaging 24-72 h after tracer administration, using low energy high resolution (LEHR) (18 patients) or medium energy general purpose (MEGP) (21 patients) collimators. A grading scale from 1 to 4 was used to express the compatibility of the (32)P images with those obtained from CT/MRI. Results. Although the image quality obtained with the MEGP collimator was visually and quantitatively better than with the LEHR (76% concordance score versus 71%, resp.), there was no statistically significant difference between them. Conclusion. The MEGP collimator is the first choice for BS SPECT imaging. However, if the collimator change is time consuming (as in a busy center) or an MEGP collimator is not available, the LEHR collimator could be practical with acceptable images, especially in a SPECT study. In addition, BS imaging is a useful method to confirm the proper distribution of radiotherapeutic agents and has good correlation with anatomical findings.
Collapse
|
27
|
Ahmadzadehfar H, Duan H, Haug AR, Walrand S, Hoffmann M. The role of SPECT/CT in radioembolization of liver tumours. Eur J Nucl Med Mol Imaging 2014; 41 Suppl 1:S115-24. [PMID: 24442600 DOI: 10.1007/s00259-013-2675-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 12/17/2013] [Indexed: 01/14/2023]
Abstract
Radioembolization (RE) with (90)Y microspheres is a promising catheter-based therapeutic option for patients with unresectable primary and metastatic liver tumours. Its rationale arises from the dual blood supply of liver tissue through the hepatic artery and the portal vein. Metastatic hepatic tumours measuring >3 mm derive 80 - 100 % of their blood supply from the arterial rather than the portal hepatic circulation. Typically, an angiographic evaluation combined with (99m)Tc-macroaggregated albumin ((99m)Tc-MAA) scan precedes therapy to map the tumour feeding vessels as well as to avoid the inadvertent deposition of microspheres in organs other than the liver. Prior to administration of (99m)Tc-MAA, prophylactic coil embolization of the gastroduodenal artery is recommended to avoid extrahepatic deposition of the microspheres. SPECT/CT allows direct correlation of anatomic and functional information in patients with unresectable liver disease. SPECT/CT is recommended to assess intrahepatic distribution as well as extrahepatic gastrointestinal uptake in these patients. Pretherapeutic SPECT/CT is an important component of treatment planning including catheter positioning and dose finding. A post-therapy bremsstrahlung (BS) scan should follow RE to verify the distribution of the administered tracer. BS SPECT/CT imaging enables better localization and definition of intrahepatic and possible extrahepatic sphere distribution and to a certain degree allows posttreatment dosimetry. In this paper we address the usefulness and significance of SPECT/CT in therapy planning and therapy monitoring of RE.
Collapse
|
28
|
Shcherbinin S, Grimes J, Bator A, Cwikla JB, Celler A. Three-dimensional personalized dosimetry for 188Re liver selective internal radiation therapy based on quantitative post-treatment SPECT studies. Phys Med Biol 2013; 59:119-134. [PMID: 24334821 DOI: 10.1088/0031-9155/59/1/119] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We demonstrate that accurate patient-specific distributions of microspheres labeled with 188Re and resulting absorbed doses can be obtained from single-photon emission computed tomography (SPECT) studies performed after 188Re selective internal radiation therapy when accurate correction methods are employed in image reconstruction. Our quantitative image reconstruction algorithm includes corrections for attenuation, resolution degradations and scatter as well as a window-based compensation for contamination. The procedure has been validated using four phantom experiments containing an 18 ml cylindrical source (82-93 MBq of 188Re activity) simulating a liver tumor. In addition, we applied our approach to post-therapy SPECT studies of ten patients with progressive primary or metastatic liver carcinomas. Our quantitative algorithm accurately (within 9%) recovered 188Re activity from four phantom experiments. In addition, for two patients that received three scans, deviations remained consistent between the measured and the reconstructed activities that were determined from studies with differing severity of the dead-time effect. The analysis of absorbed doses for patient studies allowed us to hypothesize that D90 (the minimum dose received by 90% of the tumor volume) may be a reliable metric relating therapy outcomes to the calculated doses. Among several considered metrics, only D90 showed statistically significant correlation with the overall survival.
Collapse
Affiliation(s)
- S Shcherbinin
- Medical Imaging Research Group, University of British Columbia, 366-828 West 10th Avenue, Vancouver BC, V5Z 1M9, Canada
| | | | | | | | | |
Collapse
|
29
|
Eaton BR, Kim HS, Schreibmann E, Schuster DM, Galt JR, Barron B, Kim S, Liu Y, Landry J, Fox T. Quantitative dosimetry for yttrium-90 radionuclide therapy: tumor dose predicts fluorodeoxyglucose positron emission tomography response in hepatic metastatic melanoma. J Vasc Interv Radiol 2013; 25:288-95. [PMID: 24269792 DOI: 10.1016/j.jvir.2013.08.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 08/15/2013] [Accepted: 08/26/2013] [Indexed: 12/21/2022] Open
Abstract
PURPOSE To assess a new method for generating patient-specific volumetric dose calculations and analyze the relationship between tumor dose and positron emission tomography (PET) response after radioembolization of hepatic melanoma metastases. METHODS AND MATERIALS Yttrium-90 ((90)Y) bremsstrahlung single photon emission computed tomography (SPECT)/computed tomography (CT) acquired after (90)Y radioembolization was convolved with published (90)Y Monte Carlo estimated dose deposition kernels to create a three-dimensional dose distribution. Dose-volume histograms were calculated for tumor volumes manually defined from magnetic resonance imaging or PET/CT imaging. Tumor response was assessed by absolute reduction in maximum standardized uptake value (SUV(max)) and total lesion glycolysis (TLG). RESULTS Seven patients with 30 tumors treated with (90)Y for hepatic metastatic melanoma with available (90)Y SPECT/CT and PET/CT before and after treatment were identified for analysis. The median (range) for minimum, mean, and maximum dose per tumor volume was 16.9 Gy (5.7-43.5 Gy), 28.6 Gy (13.8-65.6 Gy) and 36.6 Gy (20-124 Gy), respectively. Response was assessed by fluorodeoxyglucose PET/CT at a median time after treatment of 2.8 months (range, 1.2-7.9 months). Mean tumor dose (P = .03) and the percentage of tumor volume receiving ≥ 50 Gy (P < .01) significantly predicted for decrease in tumor SUV(max), whereas maximum tumor dose predicted for decrease in tumor TLG (P < .01). CONCLUSIONS Volumetric dose calculations showed a statistically significant association with metabolic tumor response. The significant dose-response relationship points to the clinical utility of patient-specific absorbed dose calculations for radionuclide therapy.
Collapse
Affiliation(s)
- Bree R Eaton
- Department of Radiation Oncology, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322.
| | - Hyun S Kim
- Department of Radiology and Imaging Sciences, Divisions of Interventional Radiology and Image Guided Medicine, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322
| | - Eduard Schreibmann
- Department of Radiation Oncology, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322
| | - David M Schuster
- Divisions of Nuclear Medicine and Molecular Imaging, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322
| | - James R Galt
- Divisions of Nuclear Medicine and Molecular Imaging, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322
| | - Bruce Barron
- Divisions of Nuclear Medicine and Molecular Imaging, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322
| | - Sungjin Kim
- Departments of Biostatistics and Bioinformatics, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322
| | - Yuan Liu
- Departments of Biostatistics and Bioinformatics, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322
| | - Jerome Landry
- Department of Radiation Oncology, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322
| | - Tim Fox
- Department of Radiation Oncology, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322
| |
Collapse
|
30
|
Gleisner KS, Ljungberg M. Patient-specific whole-body attenuation correction maps from a CT system for conjugate-view-based activity quantification: method development and evaluation. Cancer Biother Radiopharm 2013; 27:652-64. [PMID: 23210927 DOI: 10.1089/cbr.2011.1082] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
For activity quantification based on planar scintillation camera measurements, photon attenuation is an important factor that needs to be corrected for in a patient- and organ-specific manner. One possibility for obtaining attenuation correction maps is to use X-ray CT scout images. Since the intensity of scout images is in relative numbers, their image values need to be multiplied by a factor to become quantitative and thus useful for attenuation correction. The calibration factor can for our current imaging system be obtained from a scanner system file, but is generally not available. For this purpose, a method based on the patient weight has been developed. Results based on 79 patient scout images show that the calibration factor thus determined correlates well with values that, in this case, are independently specified by the system. The accuracy of attenuation correction factors (ACFs) derived from the scout-based attenuation correction maps is evaluated by comparison to ACFs derived from three-dimensional CT studies. For photon energies of 208, 245, and 364 keV, scout-based ACFs are on average 1.2% and 0.5% from the CT-derived values, using the system-based and the weight-based values of the scout-image calibration factor, respectively. The imprecision is somewhat higher for the weight-based method, due to variability in the delineation of the patient contour used as a part of this method. In conclusion, X-ray scouts are found useful for attenuation correction with a satisfactory accuracy obtained, both using the new, weight-based method, and using the previous, system-based method, for determining the required calibration factor.
Collapse
|
31
|
Personalized image-based radiation dosimetry for routine clinical use in peptide receptor radionuclide therapy: pretherapy experience. Recent Results Cancer Res 2013; 194:497-517. [PMID: 22918779 DOI: 10.1007/978-3-642-27994-2_29] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2023]
Abstract
Patient-specific dose calculations are not routinely performed for targeted radionuclide therapy procedures, partly because they are time consuming and challenging to perform. However, it is becoming widely recognized that a personalized dosimetry approach can help plan treatment and improve understanding of the dose-response relationship. In this chapter, we review the procedures and essential elements of an accurate internal dose calculation and propose a simplified approach that is aimed to be practical for use in a busy nuclear medicine department.
Collapse
|
32
|
Gustafsson J, Nilsson P, Gleisner KS. On the biologically effective dose (BED)-using convolution for calculating the effects of repair: II. Numerical considerations. Phys Med Biol 2013; 58:1529-48. [PMID: 23406832 DOI: 10.1088/0031-9155/58/5/1529] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have previously shown analytically that the biologically effective dose (BED), including effects of repair during irradiation and of incomplete repair between fractions, can be formulated using a convolution between the absorbed dose rate function and the function describing repair. In this work, a discrete formalism is derived along with its implementation via the fast Fourier transform. The implementation takes the intrinsic periodicity of the discrete Fourier transform into consideration, as well as possible inconsistencies that may arise due to discretization and truncation of the functions describing the absorbed dose rate and repair. Numerically and analytically calculated BED values are compared for various situations in external beam radiotherapy, brachytherapy and radionuclide therapy, including the use of different repair models. The numerical method is shown to be accurate and versatile since it can be applied to any kind of absorbed dose rate function and allows for the incorporation of different repair models. Typical accuracies for clinically realistic examples are in the order of 10(-3)% to 10(-5)%. The method has thus the potential of being a useful tool for the calculation of BED, also in situations with complicated irradiation patterns or repair functions.
Collapse
Affiliation(s)
- Johan Gustafsson
- Department of Medical Radiation Physics, Lund University, Lund, Sweden.
| | | | | |
Collapse
|
33
|
Baechler S, Hobbs RF, Boubaker A, Buchegger F, He B, Frey EC, Sgouros G. Three-dimensional radiobiological dosimetry of kidneys for treatment planning in peptide receptor radionuclide therapy. Med Phys 2012; 39:6118-28. [PMID: 23039651 DOI: 10.1118/1.4752213] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Peptide receptor radionuclide therapy (PRRT) delivers high absorbed doses to kidneys and may lead to permanent nephropathy. Reliable dosimetry of kidneys is thus critical for safe and effective PRRT. The aim of this work was to assess the feasibility of planning PRRT based on 3D radiobiological dosimetry (3D-RD) in order to optimize both the amount of activity to administer and the fractionation scheme, while limiting the absorbed dose and the biological effective dose (BED) to the renal cortex. METHODS Planar and SPECT data were available for a patient examined with (111)In-DTPA-octreotide at 0.5 (planar only), 4, 24, and 48 h post-injection. Absorbed dose and BED distributions were calculated for common therapeutic radionuclides, i.e., (111)In, (90)Y and (177)Lu, using the 3D-RD methodology. Dose-volume histograms were computed and mean absorbed doses to kidneys, renal cortices, and medullae were compared with results obtained using the MIRD schema (S-values) with the multiregion kidney dosimetry model. Two different treatment planning approaches based on (1) the fixed absorbed dose to the cortex and (2) the fixed BED to the cortex were then considered to optimize the activity to administer by varying the number of fractions. RESULTS Mean absorbed doses calculated with 3D-RD were in good agreement with those obtained with S-value-based SPECT dosimetry for (90)Y and (177)Lu. Nevertheless, for (111)In, differences of 14% and 22% were found for the whole kidneys and the cortex, respectively. Moreover, the authors found that planar-based dosimetry systematically underestimates the absorbed dose in comparison with SPECT-based methods, up to 32%. Regarding the 3D-RD-based treatment planning using a fixed BED constraint to the renal cortex, the optimal number of fractions was found to be 3 or 4, depending on the radionuclide administered and the value of the fixed BED. Cumulative activities obtained using the proposed simulated treatment planning are compatible with real activities administered to patients in PRRT. CONCLUSIONS The 3D-RD treatment planning approach based on the fixed BED was found to be the method of choice for clinical implementation in PRRT by providing realistic activity to administer and number of cycles. While dividing the activity in several cycles is important to reduce renal toxicity, the clinical outcome of fractionated PRRT should be investigated in the future.
Collapse
Affiliation(s)
- Sebastien Baechler
- Institute of Radiation Physics, Lausanne University Hospital, Lausanne, Switzerland.
| | | | | | | | | | | | | |
Collapse
|
34
|
van de Maat GH, Seevinck PR, Elschot M, Smits MLJ, de Leeuw H, van Het Schip AD, Vente MAD, Zonnenberg BA, de Jong HWAM, Lam MGEH, Viergever MA, van den Bosch MAAJ, Nijsen JFW, Bakker CJG. MRI-based biodistribution assessment of holmium-166 poly(L-lactic acid) microspheres after radioembolisation. Eur Radiol 2012; 23:827-35. [PMID: 23014797 PMCID: PMC3563959 DOI: 10.1007/s00330-012-2648-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 07/20/2012] [Accepted: 08/15/2012] [Indexed: 12/16/2022]
Abstract
Objectives To demonstrate the feasibility of MRI-based assessment of the intrahepatic Ho-PLLA-MS biodistribution after radioembolisation in order to estimate the absorbed radiation dose. Methods Fifteen patients were treated with holmium-166 (166Ho) poly(L-lactic acid)-loaded microspheres (Ho-PLLA-MS, mean 484 mg; range 408–593 mg) in a phase I study. Multi-echo gradient-echo MR images were acquired from which R2* maps were constructed. The amount of Ho-PLLA-MS in the liver was determined by using the relaxivity r2* of the Ho-PLLA-MS and compared with the administered amount. Quantitative single photon emission computed tomography (SPECT) was used for comparison with MRI regarding the whole liver absorbed radiation dose. Results R2* maps visualised the deposition of Ho-PLLA-MS with great detail. The mean total amount of Ho-PLLA-MS detected in the liver based on MRI was 431 mg (range 236–666 mg) or 89 ± 19 % of the delivered amount (correlation coefficient r = 0.7; P < 0.01). A good correlation was found between the whole liver mean absorbed radiation dose as assessed by MRI and SPECT (correlation coefficient r = 0.927; P < 0.001). Conclusion MRI-based dosimetry for holmium-166 radioembolisation is feasible. Biodistribution is visualised with great detail and quantitative measurements are possible. Key Points • Radioembolisation is increasingly used for treating unresectable primary or metastatic liver tumours. • MRI-based intrahepatic microsphere biodistribution assessment is feasible after holmium-166 radioembolisation. • MRI enables quantification of holmium-166 microspheres in liver in a short imaging time. • MRI can estimate the whole liver absorbed radiation dose following holmium-166 radioembolisation.
Collapse
Affiliation(s)
- Gerrit H van de Maat
- Image Sciences Institute, University Medical Center Utrecht, Q S.459, PO Box 85500, 3508 GA Utrecht, The Netherlands.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Shcherbinin S, Piwowarska-Bilska H, Celler A, Birkenfeld B. Quantitative SPECT/CT reconstruction for177Lu and177Lu/90Y targeted radionuclide therapies. Phys Med Biol 2012; 57:5733-47. [DOI: 10.1088/0031-9155/57/18/5733] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
36
|
Dewaraja YK, Frey EC, Sgouros G, Brill AB, Roberson P, Zanzonico PB, Ljungberg M. MIRD pamphlet No. 23: quantitative SPECT for patient-specific 3-dimensional dosimetry in internal radionuclide therapy. J Nucl Med 2012; 53:1310-25. [PMID: 22743252 DOI: 10.2967/jnumed.111.100123] [Citation(s) in RCA: 241] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In internal radionuclide therapy, a growing interest in voxel-level estimates of tissue-absorbed dose has been driven by the desire to report radiobiologic quantities that account for the biologic consequences of both spatial and temporal nonuniformities in these dose estimates. This report presents an overview of 3-dimensional SPECT methods and requirements for internal dosimetry at both regional and voxel levels. Combined SPECT/CT image-based methods are emphasized, because the CT-derived anatomic information allows one to address multiple technical factors that affect SPECT quantification while facilitating the patient-specific voxel-level dosimetry calculation itself. SPECT imaging and reconstruction techniques for quantification in radionuclide therapy are not necessarily the same as those designed to optimize diagnostic imaging quality. The current overview is intended as an introduction to an upcoming series of MIRD pamphlets with detailed radionuclide-specific recommendations intended to provide best-practice SPECT quantification-based guidance for radionuclide dosimetry.
Collapse
Affiliation(s)
- Yuni K Dewaraja
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | | | | | | | | | | | | |
Collapse
|
37
|
Feasibility of bremsstrahlung dosimetry for direct dose estimation in patients undergoing treatment with 90Y-ibritumomab tiuxetan. Eur J Nucl Med Mol Imaging 2012; 39:956-66. [DOI: 10.1007/s00259-011-2040-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 12/13/2011] [Indexed: 10/14/2022]
|
38
|
Ljungberg M, Sjögreen-Gleisner K. The accuracy of absorbed dose estimates in tumours determined by quantitative SPECT: a Monte Carlo study. Acta Oncol 2011; 50:981-9. [PMID: 21767200 DOI: 10.3109/0284186x.2011.584559] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Dosimetry in radionuclide therapy estimates delivered absorbed doses to tumours and ensures that absorbed dose levels to normal organs are below tolerance levels. One procedure is to determine time-activity curves in volumes-of-interests from which the absorbed dose is estimated using SPECT with appropriate corrections for attenuation, scatter and collimator response. From corrected SPECT images the absorbed energy can be calculated by (a) assuming kinetic energy deposited in the same voxel where particles were emitted, (b) convolve with point-dose kernels or (c) use full Monte Carlo (MC) methods. A question arises which dosimetry method is optimal given the limitations in reconstruction- and quantification procedures. METHODS Dosimetry methods (a) and (c) were evaluated by comparing dose-rate volume histograms (DrVHs) from simulated SPECT of (111)In, (177)Lu, (131)I and bremsstrahlung from (90)Y to match true dose rate images. The study used a voxel-based phantom with different tumours in the liver. SPECT reconstruction was made using an iterative OSEM method and MC dosimetry was performed using a charged-particle EGS4 program that also was used to determined true absorbed dose rate distributions for the same phantom geometry but without camera limitations. RESULTS The DrVHs obtained from SPECT differed from true DrVH mainly due to limited spatial resolution. MC dosimetry had a marginal effect because the SPECT spatial resolution is in the same order as the energy distribution caused by the electron track ranges. For (131)I, full MC dosimetry made a difference due to the additional contribution from high-energy photons. SPECT-based DrVHs differ significantly from true DrVHs unless the tumours are considerable larger than the spatial resolution. CONCLUSION It is important to understand limitations in quantitative SPECT images and the reasons for apparent heterogeneities since these have an impact on dose-volume histograms. A MC-based dosimetry calculation from SPECT images is not always warranted.
Collapse
Affiliation(s)
- Michael Ljungberg
- Department of Medical Radiation Physics, Clinical Sciences, Lund, Lund University, Lund, Sweden.
| | | |
Collapse
|