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Zhao X, Jakobsson V, Tao Y, Zhao T, Wang J, Khong PL, Chen X, Zhang J. Targeted Radionuclide Therapy in Glioblastoma. ACS APPLIED MATERIALS & INTERFACES 2024. [PMID: 39042829 DOI: 10.1021/acsami.4c07850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/25/2024]
Abstract
Despite the development of various novel therapies, glioblastoma (GBM) remains a devastating disease, with a median survival of less than 15 months. Recently, targeted radionuclide therapy has shown significant progress in treating solid tumors, with the approval of Lutathera for neuroendocrine tumors and Pluvicto for prostate cancer by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA). This achievement has shed light on the potential of targeted radionuclide therapy for other solid tumors, including GBM. This review presents the current status of targeted radionuclide therapy in GBM, highlighting the commonly used therapeutic radionuclides emitting alpha, beta particles, and Auger electrons that could induce potent molecular and cellular damage to treat GBM. We then explore a range of targeting vectors, including small molecules, peptides, and antibodies, which selectively target antigen-expressing tumor cells with minimal or no binding to healthy tissues. Considering that radiopharmaceuticals for GBM are often administered locoregionally to bypass the blood-brain barrier (BBB), we review prominent delivery methods such as convection-enhanced delivery, local implantation, and stereotactic injections. Finally, we address the challenges of this therapeutic approach for GBM and propose potential solutions.
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Affiliation(s)
- Xiaobin Zhao
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore 119074, Singapore
- Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117599, Singapore
- Theranostics Center of Excellence, Yong Loo Lin School of Medicine, National University of Singapore, 11 Biopolis Way, Helios, Singapore 138667, Singapore
- Department of Nuclear Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
| | - Vivianne Jakobsson
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore 119074, Singapore
- Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117599, Singapore
- Theranostics Center of Excellence, Yong Loo Lin School of Medicine, National University of Singapore, 11 Biopolis Way, Helios, Singapore 138667, Singapore
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
| | - Yucen Tao
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore 119074, Singapore
- Theranostics Center of Excellence, Yong Loo Lin School of Medicine, National University of Singapore, 11 Biopolis Way, Helios, Singapore 138667, Singapore
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
| | - Tianzhi Zhao
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore 119074, Singapore
- Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117599, Singapore
- Theranostics Center of Excellence, Yong Loo Lin School of Medicine, National University of Singapore, 11 Biopolis Way, Helios, Singapore 138667, Singapore
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
| | - Jingyan Wang
- Xiamen University, School of Public Health, Xiang'an South Road, Xiamen 361102, China
| | - Pek-Lan Khong
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore 119074, Singapore
- Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117599, Singapore
| | - Xiaoyuan Chen
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore 119074, Singapore
- Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117599, Singapore
- Theranostics Center of Excellence, Yong Loo Lin School of Medicine, National University of Singapore, 11 Biopolis Way, Helios, Singapore 138667, Singapore
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
- Departments of Surgery, Chemical and Biomolecular Engineering, and Biomedical Engineering, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore 119074, Singapore
- Institute of Molecular and Cell Biology, Agency for Science, Technology, and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore 138673, Singapore
| | - Jingjing Zhang
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore 119074, Singapore
- Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117599, Singapore
- Theranostics Center of Excellence, Yong Loo Lin School of Medicine, National University of Singapore, 11 Biopolis Way, Helios, Singapore 138667, Singapore
- Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
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Vallot D, Brillouet S, Pondard S, Vija L, Texier JS, Dierickx L, Courbon F. Impact of different models based on blood samples and images for bone marrow dosimetry after 177Lu-labeled somatostatin-receptor therapy. EJNMMI Phys 2024; 11:32. [PMID: 38564043 PMCID: PMC10987460 DOI: 10.1186/s40658-024-00615-5] [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: 04/28/2023] [Accepted: 01/15/2024] [Indexed: 04/04/2024] Open
Abstract
BACKGROUND Peptide receptor radionuclide therapy with 177Lu-DOTATATE is a recognized option for treating neuroendocrine tumors and has few toxicities, except for the kidneys and bone marrow. The bone marrow dose is generally derived from a SPECT/CT image-based method with four timepoints or from a blood-based method with up to 9 timepoints, but there is still no reference method. This retrospective single-center study on the same cohort of patients compared the calculated bone marrow dose administered with both methods using mono, bi- or tri-exponential models. For the image-based method, the dose was estimated using Planetdose© software. Pearson correlation coefficients were calculated. We also studied the impact of late timepoints for both methods. RESULTS The bone marrow dose was calculated for 131 treatments with the blood-based method and for 17 with the image-based method. In the former, the median absorbed dose was 15.3, 20.5 and 28.3 mGy/GBq with the mono-, bi- and tri-exponential model, respectively. With the image-based method, the median absorbed dose was 63.9, 41.9 and 60.8 with the mono-, bi- and tri-exponential model, respectively. Blood samples after 24h post-injection did not evidence any change in the absorbed bone marrow dose with the bi-exponential model. On the contrary, the 6-day post-injection timepoint was more informative with the image-based model. CONCLUSION This study confirms that the estimated bone marrow dose is significantly lower with the blood-based method than with the image-based method. The blood-based method with a bi-exponential model proved particularly useful, without the need for blood samples after 24h post-injection. Nevertheless, this blood-based method is based on an assumption that needs to be more validated. The important difference between the two methods does not allow to determine the optimal one to estimate the true absorbed dose and further studies are necessary to compare with biological effects.
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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.
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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
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Siebinga H, de Wit-van der Veen BJ, Beijnen JH, Stokkel MPM, Dorlo TPC, Huitema ADR, Hendrikx JJMA. Predicting [ 177Lu]Lu-HA-DOTATATE kidney and tumor accumulation based on [ 68Ga]Ga-HA-DOTATATE diagnostic imaging using semi-physiological population pharmacokinetic modeling. EJNMMI Phys 2023; 10:48. [PMID: 37615812 PMCID: PMC10449733 DOI: 10.1186/s40658-023-00565-4] [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: 03/20/2023] [Accepted: 07/24/2023] [Indexed: 08/25/2023] Open
Abstract
BACKGROUND Prediction of [177Lu]Lu-HA-DOTATATE kidney and tumor uptake based on diagnostic [68Ga]Ga-HA-DOTATATE imaging would be a crucial step for precision dosing of [177Lu]Lu-HA-DOTATATE. In this study, the population pharmacokinetic (PK) differences between [177Lu]Lu-HA-DOTATATE and [68Ga]Ga-HA-DOTATATE were assessed and subsequently [177Lu]Lu-HA-DOTATATE was predicted based on [68Ga]Ga-HA-DOTATATE imaging. METHODS A semi-physiological nonlinear mixed-effects model was developed for [68Ga]Ga-HA-DOTATATE and [177Lu]Lu-HA-DOTATATE, including six compartments (representing blood, spleen, kidney, tumor lesions, other somatostatin receptor expressing organs and a lumped rest compartment). Model parameters were fixed based on a previously developed physiologically based pharmacokinetic model for [68Ga]Ga-HA-DOTATATE. For [177Lu]Lu-HA-DOTATATE, PK parameters were based on literature values or estimated based on scan data (four time points post-injection) from nine patients. Finally, individual [177Lu]Lu-HA-DOTATATE uptake into tumors and kidneys was predicted based on individual [68Ga]Ga-HA-DOTATATE scan data using Bayesian estimates. Predictions were evaluated compared to observed data using a relative prediction error (RPE) for both area under the curve (AUC) and absorbed dose. Lastly, to assess the predictive value of diagnostic imaging to predict therapeutic exposure, individual prediction RPEs (using Bayesian estimation) were compared to those from population predictions (using the population model). RESULTS Population uptake rate parameters for spleen, kidney and tumors differed by a 0.29-fold (15% relative standard error (RSE)), 0.49-fold (15% RSE) and 1.43-fold (14% RSE), respectively, for [177Lu]Lu-HA-DOTATATE compared to [68Ga]Ga-HA-DOTATATE. Model predictions adequately described observed data in kidney and tumors for both peptides (based on visual inspection of goodness-of-fit plots). Individual predictions of tumor uptake were better (RPE AUC -40 to 28%) compared to kidney predictions (RPE AUC -53 to 41%). Absorbed dose predictions were less predictive for both tumor and kidneys (RPE tumor and kidney -51 to 44% and -58 to 82%, respectively). For most patients, [177Lu]Lu-HA-DOTATATE tumor accumulation predictions based on individual PK parameters estimated from diagnostic imaging outperformed predictions based on population parameters. CONCLUSION Our semi-physiological PK model indicated clear differences in PK parameters for [68Ga]Ga-HA-DOTATATE and [177Lu]Lu-HA-DOTATATE. Diagnostic images provided additional information to individually predict [177Lu]Lu-HA-DOTATATE tumor uptake compared to using a population approach. In addition, individual predictions indicated that many aspects, apart from PK differences, play a part in predicting [177Lu]Lu-HA-DOTATATE distribution.
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Affiliation(s)
- Hinke Siebinga
- Department of Pharmacy and Pharmacology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands.
- Department of Nuclear Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
- Graduate School of Life Sciences, Utrecht University, Utrecht, The Netherlands.
| | | | - Jos H Beijnen
- Department of Pharmacy and Pharmacology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - Marcel P M Stokkel
- Department of Nuclear Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Thomas P C Dorlo
- Department of Pharmacy and Pharmacology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
- Department of Pharmacy, Uppsala University, Uppsala, Sweden
| | - Alwin D R Huitema
- Department of Pharmacy and Pharmacology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
- Department of Clinical Pharmacy, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
- Department of Pharmacology, Princess Máxima Center for Pediatric Oncology, Utrecht, The Netherlands
| | - Jeroen J M A Hendrikx
- Department of Pharmacy and Pharmacology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
- Department of Nuclear Medicine, The Netherlands Cancer Institute, Amsterdam, The Netherlands
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Akhavanallaf A, Peterson AB, Fitzpatrick K, Roseland M, Wong KK, El-Naqa I, Zaidi H, Dewaraja YK. The predictive value of pretherapy [ 68Ga]Ga-DOTA-TATE PET and biomarkers in [ 177Lu]Lu-PRRT tumor dosimetry. Eur J Nucl Med Mol Imaging 2023; 50:2984-2996. [PMID: 37171633 PMCID: PMC10981963 DOI: 10.1007/s00259-023-06252-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 04/24/2023] [Indexed: 05/13/2023]
Abstract
PURPOSE Metastatic neuroendocrine tumors (NETs) overexpressing type 2 somatostatin receptors are the target for peptide receptor radionuclide therapy (PRRT) through the theragnostic pair of 68Ga/177Lu-DOTATATE. The main purpose of this study was to develop machine learning models to predict therapeutic tumor dose using pre therapy 68Ga -PET and clinicopathological biomarkers. METHODS We retrospectively analyzed 90 segmented metastatic NETs from 25 patients (M14/F11, age 63.7 ± 9.5, range 38-76) treated by 177Lu-DOTATATE at our institute. Patients underwent both pretherapy [68Ga]Ga-DOTA-TATE PET/CT and four timepoints SPECT/CT at ~ 4, 24, 96, and 168 h post-177Lu-DOTATATE infusion. Tumors were segmented by a radiologist on baseline CT or MRI and transferred to co-registered PET/CT and SPECT/CT, and normal organs were segmented by deep learning-based method on CT of the PET and SPECT. The SUV metrics and tumor-to-normal tissue SUV ratios (SUV_TNRs) were calculated from 68Ga -PET at the contour-level. Posttherapy dosimetry was performed based on the co-registration of SPECT/CTs to generate time-integrated-activity, followed by an in-house Monte Carlo-based absorbed dose estimation. The correlation between delivered 177Lu Tumor absorbed dose and PET-derived metrics along with baseline clinicopathological biomarkers (such as Creatinine, Chromogranin A and prior therapies) were evaluated. Multiple interpretable machine-learning algorithms were developed to predict tumor dose using these pretherapy information. Model performance on a nested tenfold cross-validation was evaluated in terms of coefficient of determination (R2), mean-absolute-error (MAE), and mean-relative-absolute-error (MRAE). RESULTS SUVmean showed a significant correlation (q-value < 0.05) with absorbed dose (Spearman ρ = 0.64), followed by TLSUVmean (SUVmean of total-lesion-burden) and SUVpeak (ρ = 0.45 and 0.41, respectively). The predictive value of PET-SUVmean in estimation of posttherapy absorbed dose was stronger compared to PET-SUVpeak, and SUV_TNRs in terms of univariate analysis (R2 = 0.28 vs. R2 ≤ 0.12). An optimal trivariate random forest model composed of SUVmean, TLSUVmean, and total liver SUVmean (normal and tumoral liver) provided the best performance in tumor dose prediction with R2 = 0.64, MAE = 0.73 Gy/GBq, and MRAE = 0.2. CONCLUSION Our preliminary results demonstrate the feasibility of using baseline PET images for prediction of absorbed dose prior to 177Lu-PRRT. Machine learning models combining multiple PET-based metrics performed better than using a single SUV value and using other investigated clinicopathological biomarkers. Developing such quantitative models forms the groundwork for the role of 68Ga -PET not only for the implementation of personalized treatment planning but also for patient stratification in the era of precision medicine.
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Affiliation(s)
- Azadeh Akhavanallaf
- Department of Radiology, University of Michigan, 1301 Catherine, 2276 Medical Science I/5610, Ann Arbor, MI, 48109, USA.
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211, Geneva, Switzerland.
| | - Avery B Peterson
- Department of Radiology, University of Michigan, 1301 Catherine, 2276 Medical Science I/5610, Ann Arbor, MI, 48109, USA
| | - Kellen Fitzpatrick
- Department of Radiology, University of Michigan, 1301 Catherine, 2276 Medical Science I/5610, Ann Arbor, MI, 48109, USA
| | - Molly Roseland
- Department of Radiology, University of Michigan, 1301 Catherine, 2276 Medical Science I/5610, Ann Arbor, MI, 48109, USA
| | - Ka Kit Wong
- Department of Radiology, University of Michigan, 1301 Catherine, 2276 Medical Science I/5610, Ann Arbor, MI, 48109, USA
| | - Issam El-Naqa
- Department of Machine Learning, Moffitt Cancer Center, Tampa, FL, USA
| | - Habib Zaidi
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211, Geneva, Switzerland
- Geneva University Neurocenter, Geneva University, CH-1205, Geneva, Switzerland
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, 9700 RB, Groningen, Netherlands
- Department of Nuclear Medicine, University of Southern Denmark, DK-500, Odense, Denmark
| | - Yuni K Dewaraja
- Department of Radiology, University of Michigan, 1301 Catherine, 2276 Medical Science I/5610, Ann Arbor, MI, 48109, USA
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Jahn U, Garske-Román U, Sandström M, Lubberink M, Sundin A. Impact of administered amount of peptide on tumor dosimetry at the first cycle of peptide receptor radionuclide therapy (PRRT) in relation to total tumor somatostatin receptor expression. EJNMMI Res 2023; 13:45. [PMID: 37204528 DOI: 10.1186/s13550-023-00997-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 05/08/2023] [Indexed: 05/20/2023] Open
Abstract
BACKGROUND The accumulation of 177Lu-DOTATATE might be influenced by the amount of administered peptide in relation to the tumor somatostatin receptor expression. The effect of the administered peptide mass on the resulting absorbed dose in tumors and normal organs has not previously been assessed in relation to the patients' tumor load. METHOD Patients with small intestinal (n = 141) and pancreatic (n = 62) neuroendocrine tumors (NETs) who underwent PRRT were selected for retrospective evaluation. All patients had received 7.4 GBq 177Lu-DOTATATE, and the amount of administered peptide in the preparation varied from 93 to 456 µg. The absorbed dose in tumors and normal tissue at the first PRRT cycle was calculated, based on SPECT-measurements at day 1, 4, and 7 post-infusion. The total tumor somatostatin receptor expression (tTSSTRE) was calculated on SPECT after 24 h by multiplying the functional tumor volume, delineated by 42% cut-off VOIs of the highest activity, with the SUVmean for the respective tumor VOIs. Spearman's rank correlation analyzed any relationship between the administered amount of peptide and the absorbed dose in tumors and normal organs, in relation to the patients' tTSSTRE. RESULTS There was no correlation between the amount of peptide and any of the tested parameters in relation to tTSSTRE. CONCLUSION In this retrospective analysis, no correlation between the amount of administered peptide in the 177Lu-DOTATATE preparation and the absorbed radiation doses in tumors and normal tissues was demonstrated in relation to the total tumor SSTR expression.
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Affiliation(s)
- Ulrika Jahn
- Department of Surgical Sciences, Nuclear Medicine and PET, Uppsala University Hospital, 751 85, Uppsala, Sweden.
- Medical Imaging Centre, Uppsala University Hospital, Uppsala, Sweden.
| | - Ulrike Garske-Román
- Department of Blood and Tumor Diseases, Uppsala University Hospital, Uppsala, Sweden
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Mattias Sandström
- Department of Surgical Sciences, Nuclear Medicine and PET, Uppsala University Hospital, 751 85, Uppsala, Sweden
- Department of Medical Physics, Uppsala University Hospital, Uppsala, Sweden
| | - Mark Lubberink
- Department of Surgical Sciences, Nuclear Medicine and PET, Uppsala University Hospital, 751 85, Uppsala, Sweden
- Department of Medical Physics, Uppsala University Hospital, Uppsala, Sweden
| | - Anders Sundin
- Department of Surgical Sciences, Nuclear Medicine and PET, Uppsala University Hospital, 751 85, Uppsala, Sweden
- Medical Imaging Centre, Uppsala University Hospital, Uppsala, Sweden
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Barakat A, Santoro L, Vivien M, Kotzki PO, Deshayes E, Khier S. Clinical Pharmacokinetics of Radiopharmaceuticals from SPECT/CT Image Acquisition by Contouring in Patients with Gastroenteropancreatic Neuroendocrine Tumors: Lu-177 DOTATATE (Lutathera ®) Case. Eur J Drug Metab Pharmacokinet 2023:10.1007/s13318-023-00829-5. [PMID: 37184824 DOI: 10.1007/s13318-023-00829-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/19/2023] [Indexed: 05/16/2023]
Abstract
BACKGROUND AND OBJECTIVE Lu-177 DOTATATE (Lutathera®) is a radiolabeled analog of somatostatin administered intravenously in patients with somatostatin receptor-positive gastroenteropancreatic neuroendocrine tumors. Biodistribution of Lu-177 DOTATATE in tumor and healthy tissues can be monitored by serial post-injection scintigraphy imaging. Patient exposure to the drug is variable with the recommended fixed dosage, and hence there is a variable response to treatment. The aim of this work was to study the pharmacokinetics of Lu-177 DOTATATE by a population modeling approach, based on single-photon emission computed tomography (SPECT)/computed tomography (CT) images used as surrogate of plasma concentrations to study the interindividual variability and finally optimize an individual dosage. METHODS From a retrospective study, SPECT/CT images were acquired at 4 h, 24 h, 72 h, and 192 h postadministration. From these images, volumic activities were calculated in blood and bone marrow. An individual non-compartmental pharmacokinetic analysis was performed, and the mean pharmacokinetic parameters of each tissue were compared together and with reference data. Blood volumic activities were then used to perform a population pharmacokinetic analysis (NONMEM). RESULTS The pharmacokinetic parameters (non-compartmental analysis) obtained from blood (clearance [CL] = 2.65 L/h, volume of distribution at steady state [Vss] = 309 L, elimination half-life [t1/2] = 86.3 h) and bone marrow (CL =1.68 L/h, Vss = 233 L, t1/2 = 98.8 h) were statistically different from each other and from reference values (CL = 4.50 L/h, Vss = 460 L, t1/2 = 71.0 h) published in the literature. SPECT/CT blood images were used as a surrogate of plasma concentrations to develop a population pharmacokinetic model. Weight was identified as covariate on volume of the central compartment, reducing the interindividual variability of all population pharmacokinetic parameters. CONCLUSION This study is a proof of concept that obtaining pharmacokinetic parameters with image-based blood concentration is possible. Obtaining observed concentrations from SPECT/CT images, without the need for blood sampling, is a real advantage for the patient and the drug monitoring. Pharmacokinetic modeling could be combined with a deep learning model for automatic contouring and allow precise patient-specific dose adjustment in a non-invasive manner.
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Affiliation(s)
- Anissa Barakat
- Pharmacokinetics and Pharmacometrics Department, School of Pharmacy, UFR Pharmacie, Montpellier University, 15 Avenue Charles Flahault, 34000, Montpellier, France
- Probabilities and Statistics Department, Institut Montpelliérain Alexander Grothendieck (IMAG), CNRS, UMR 5149, Inria, Montpellier University, Montpellier, France
- Nuclear Medicine Department, Montpellier Cancer Institute, Montpellier University, Montpellier, France
| | - Lore Santoro
- Nuclear Medicine Department, Montpellier Cancer Institute, Montpellier University, Montpellier, France
- Institut de Recherche en Cancérologie de Montpellier (IRCM), INSERM U1194, Montpellier University, Montpellier, France
| | - Myrtille Vivien
- Biostatistics, Informatics and pharmaceutical physic Laboratory, School of Pharmacy, UFR Pharmacie, Montpellier University, 15 Av. Ch. Flahault, 34000, Montpellier, France
- Institute of Functional Genomic (IGF)- UMR 5203, INSERM U1191, Montpellier, France
| | - Pierre-Olivier Kotzki
- Nuclear Medicine Department, Montpellier Cancer Institute, Montpellier University, Montpellier, France
- Institut de Recherche en Cancérologie de Montpellier (IRCM), INSERM U1194, Montpellier University, Montpellier, France
| | - Emmanuel Deshayes
- Nuclear Medicine Department, Montpellier Cancer Institute, Montpellier University, Montpellier, France
- Institut de Recherche en Cancérologie de Montpellier (IRCM), INSERM U1194, Montpellier University, Montpellier, France
| | - Sonia Khier
- Pharmacokinetics and Pharmacometrics Department, School of Pharmacy, UFR Pharmacie, Montpellier University, 15 Avenue Charles Flahault, 34000, Montpellier, France.
- Probabilities and Statistics Department, Institut Montpelliérain Alexander Grothendieck (IMAG), CNRS, UMR 5149, Inria, Montpellier University, Montpellier, France.
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Hänscheid H, Lassmann M, Verburg FA. Determinants of target absorbed dose in radionuclide therapy. Z Med Phys 2023; 33:82-90. [PMID: 36376202 PMCID: PMC10068538 DOI: 10.1016/j.zemedi.2022.10.001] [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: 07/27/2022] [Revised: 09/28/2022] [Accepted: 10/04/2022] [Indexed: 11/13/2022]
Abstract
In radionuclide therapy, activity kinetics in tissues determine the absorbed doses administered and thus efficacy and side effects of treatment. The objective of this work was to derive expressions for the parameters affecting the absorbed dose to a target tissue for first-order activity kinetics. The activity uptake results from contributions from the first-pass activity flow through the target tissue preceding systemic equilibration and uptake after distribution of the administered compound in the body. The absorbed dose from uptake after equilibration is the product of the mean energy deposited per decay in the target tissue, the time integral of the plasma activity concentration, the plasma volume flow per unit target tissue mass, the probability of activity removal during passage, and the mean lifetime of activity in the target tissue. Quantitative analysis of the determinants of absorbed dose exemplarily for radioiodine therapy indicates that the high uptake often observed in Graves' disease must be associated with high tissue perfusion and removal probability and that administration of stable iodine increases mean lifetime. For therapies with long residence times of the active compound in the blood, such as radioiodine therapy, the contribution of the first-pass is small compared with uptake after equilibration. The relative first-pass contribution is higher for agents that are rapidly eliminated from the blood pool, such as radiolabelled somatostatin analogues, and may dominate after arterial application. Understanding the determining parameters in radionuclide therapy reveals dose-limiting factors and opens up opportunities to optimise and individualize therapy, potentially improving treatment success rates.
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Affiliation(s)
- Heribert Hänscheid
- Department of Nuclear Medicine, University Hospital Würzburg, Würzburg, Germany.
| | - Michael Lassmann
- Department of Nuclear Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Frederik A Verburg
- Department of Radiology and Nuclear Medicine, Erasmus University Medical Center, Rotterdam, the Netherlands
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Exploring the Potential of High-Molar-Activity Samarium-153 for Targeted Radionuclide Therapy with [ 153Sm]Sm-DOTA-TATE. Pharmaceutics 2022; 14:pharmaceutics14122566. [PMID: 36559060 PMCID: PMC9785812 DOI: 10.3390/pharmaceutics14122566] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/12/2022] [Accepted: 11/18/2022] [Indexed: 11/24/2022] Open
Abstract
Samarium-153 is a promising theranostic radionuclide, but low molar activities (Am) resulting from its current production route render it unsuitable for targeted radionuclide therapy (TRNT). Recent efforts combining neutron activation of 152Sm in the SCK CEN BR2 reactor with mass separation at CERN/MEDICIS yielded high-Am 153Sm. In this proof-of-concept study, we further evaluated the potential of high-Am 153Sm for TRNT by radiolabeling to DOTA-TATE, a well-established carrier molecule binding the somatostatin receptor 2 (SSTR2) that is highly expressed in gastroenteropancreatic neuroendocrine tumors. DOTA-TATE was labeled with 153Sm and remained stable up to 7 days in relevant media. The binding specificity and high internalization rate were validated on SSTR2-expressing CA20948 cells. In vitro biological evaluation showed that [153Sm]Sm-DOTA-TATE was able to reduce CA20948 cell viability and clonogenic potential in an activity-dependent manner. Biodistribution studies in healthy and CA20948 xenografted mice revealed that [153Sm]Sm-DOTA-TATE was rapidly cleared and profound tumor uptake and retention was observed whilst these were limited in normal tissues. This proof-of-concept study showed the potential of mass-separated 153Sm for TRNT and could open doors towards wider applications of mass separation in medical isotope production.
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Koziorowski J, Ballinger J. Theragnostic radionuclides: a clinical perspective. 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... 2021; 65:306-314. [PMID: 34881851 DOI: 10.23736/s1824-4785.21.03424-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The concept of theragnostics goes back to the earliest days of nuclear medicine, with [123I/131I]iodide in thyroid disease and [123I/131I]MIBG in phaeochromocytoma being examples in long-term use. However, in recent years there has been a great expansion in the application of theragnostics, beginning with [68Ga/177Lu]-labelled somatostatin peptides for evaluation and treatment of neuroendocrine tumors. We are currently seeing the rapid development of [68Ga/177Lu]PSMA theragnostics in metastatic prostate cancer. While these applications are very promising, there are a number of practicalities which must be addressed in the development and introduction of novel theragnostics. The physical half-lives of the diagnostic and therapeutic radionuclides must be appropriate for imaging and delivery of targeted cell killing, respectively. The types of radioactive emissions are critical; beta particles can traverse several millimeters but also risk damaging non-target tissues, while alpha particles deliver their energy over a much shorter path length, a few cell diameters, and must be more directly targeted. It must be practical to produce the therapeutic radionuclide and the final radiopharmaceutical and deliver them to the final user within an appropriate time-frame determined by half-life and stability. The biodistribution of the agent must demonstrate adequate accumulation and retention in the target tissue with clearance from adjacent and/or radio-sensitive normal tissues. The commercial success of recently introduced theragnostics suggests a rosy future for personalized medicine.
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Walrand S, Jamar F. Renal and Red Marrow Dosimetry in Peptide Receptor Radionuclide Therapy: 20 Years of History and Ahead. Int J Mol Sci 2021; 22:ijms22158326. [PMID: 34361092 PMCID: PMC8347073 DOI: 10.3390/ijms22158326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/28/2021] [Accepted: 07/31/2021] [Indexed: 11/16/2022] Open
Abstract
The development of dosimetry and studies in peptide receptor radionuclide therapy (PRRT) over the past two decades are reviewed. Differences in kidney and bone marrow toxicity reported between 90Y, 177Lu and external beam radiotherapy (EBRT) are discussed with regard to the physical properties of these beta emitter radionuclides. The impact of these properties on the response to small and large tumors is also considered. Capacities of the imaging modalities to assess the dosimetry to target tissues are evaluated. Studies published in the past two years that confirm a red marrow uptake in 177Lu-DOTATATE therapy, as already observed 20 years ago in 86Y-DOTATOC PET studies, are analyzed in light of the recent developments in the transferrin transport mechanism. The review enlightens the importance (i) of using state-of-the-art imaging modalities, (ii) of individualizing the activity to be injected with regard to the huge tissue uptake variability observed between patients, (iii) of challenging the currently used but inappropriate blood-based red marrow dosimetry and (iv) of considering individual tandem therapy. Last, a smart individually optimized tandem therapy taking benefit of the bi-orthogonal toxicity-response pattern of 177Lu-DOTATATE and of 90Y-DOTATOC is proposed.
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12
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Sneddon D, Cornelissen B. Emerging chelators for nuclear imaging. Curr Opin Chem Biol 2021; 63:152-162. [PMID: 34051509 DOI: 10.1016/j.cbpa.2021.03.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 02/28/2021] [Accepted: 03/09/2021] [Indexed: 11/25/2022]
Abstract
Chelators are necessary in nuclear medicine imaging to direct an inorganic radionuclide, a radiometal, to a desired target; unfortunately, there is no 'one-size-fits-all' chelator. As the toolbox of radiometals is expanding, new chelators are required to prevent off-target side effects. 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) is the current gold standard chelator for several radiometals, but typically, chelation requires harsh conditions, making it unsuitable to label biological vectors. The ideal chelator would allow labelling under mild conditions (near-neutral pH and low temperatures [∼37 °C]) and be both thermodynamically and kinetically stable. Over the past 2-3 years, several exciting chelators have been developed that have superior properties to make them worth investigating for future clinical applications.
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Affiliation(s)
- Deborah Sneddon
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, OX3 7LE, United Kingdom.
| | - Bart Cornelissen
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, OX3 7LE, United Kingdom
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Bolcaen J, Kleynhans J, Nair S, Verhoeven J, Goethals I, Sathekge M, Vandevoorde C, Ebenhan T. A perspective on the radiopharmaceutical requirements for imaging and therapy of glioblastoma. Theranostics 2021; 11:7911-7947. [PMID: 34335972 PMCID: PMC8315062 DOI: 10.7150/thno.56639] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 03/29/2021] [Indexed: 11/26/2022] Open
Abstract
Despite numerous clinical trials and pre-clinical developments, the treatment of glioblastoma (GB) remains a challenge. The current survival rate of GB averages one year, even with an optimal standard of care. However, the future promises efficient patient-tailored treatments, including targeted radionuclide therapy (TRT). Advances in radiopharmaceutical development have unlocked the possibility to assess disease at the molecular level allowing individual diagnosis. This leads to the possibility of choosing a tailored, targeted approach for therapeutic modalities. Therapeutic modalities based on radiopharmaceuticals are an exciting development with great potential to promote a personalised approach to medicine. However, an effective targeted radionuclide therapy (TRT) for the treatment of GB entails caveats and requisites. This review provides an overview of existing nuclear imaging and TRT strategies for GB. A critical discussion of the optimal characteristics for new GB targeting therapeutic radiopharmaceuticals and clinical indications are provided. Considerations for target selection are discussed, i.e. specific presence of the target, expression level and pharmacological access to the target, with particular attention to blood-brain barrier crossing. An overview of the most promising radionuclides is given along with a validation of the relevant radiopharmaceuticals and theranostic agents (based on small molecules, peptides and monoclonal antibodies). Moreover, toxicity issues and safety pharmacology aspects will be presented, both in general and for the brain in particular.
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Affiliation(s)
- Julie Bolcaen
- Radiobiology, Radiation Biophysics Division, Nuclear Medicine Department, iThemba LABS, Cape Town, South Africa
| | - Janke Kleynhans
- Nuclear Medicine Research Infrastructure NPC, Pretoria, South Africa
- Nuclear Medicine Department, University of Pretoria and Steve Biko Academic Hospital, Pretoria, South Africa
| | - Shankari Nair
- Radiobiology, Radiation Biophysics Division, Nuclear Medicine Department, iThemba LABS, Cape Town, South Africa
| | | | - Ingeborg Goethals
- Ghent University Hospital, Department of Nuclear Medicine, Ghent, Belgium
| | - Mike Sathekge
- Nuclear Medicine Research Infrastructure NPC, Pretoria, South Africa
- Nuclear Medicine Department, University of Pretoria and Steve Biko Academic Hospital, Pretoria, South Africa
| | - Charlot Vandevoorde
- Radiobiology, Radiation Biophysics Division, Nuclear Medicine Department, iThemba LABS, Cape Town, South Africa
| | - Thomas Ebenhan
- Nuclear Medicine Research Infrastructure NPC, Pretoria, South Africa
- Nuclear Medicine Department, University of Pretoria, Pretoria, South Africa
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14
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Merrick MJ, Rotsch DA, Tiwari A, Nolen J, Brossard T, Song J, Wadas TJ, Sunderland JJ, Graves SA. Imaging and dosimetric characteristics of 67 Cu. Phys Med Biol 2021; 66:035002. [PMID: 33496267 DOI: 10.1088/1361-6560/abca52] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In recent years the use of beta-emitting radiopharmaceuticals for cancer therapy has expanded rapidly following development of therapeutics for neuroendocrine tumors, prostate cancer, and other oncologic malignancies. One emerging beta-emitting radioisotope of interest for therapy is 67Cu (t1/2: 2.6 d) due to its chemical equivalency with the widely-established positron-emitting isotope 64Cu (t1/2: 12.7 h). In this work we evaluate both the imaging and dosimetric characteristics of 67Cu, as well as producing the first report of SPECT/CT imaging using 67Cu. To this end, 67Cu was produced by photon-induced reactions on isotopically-enriched 68Zn at the Low-Energy Accelerator Facility (LEAF) of Argonne National Laboratory, followed by bulk separation of metallic 68Zn by sublimation and radiochemical purification by column chromatography. Gamma spectrometry was performed by efficiency-calibrated high-purity germanium (HPGe) analysis to verify absolute activity calibration and establish radionuclidic purity. Absolute activity measurements corroborated manufacturer-recommended dose-calibrator settings and no radionuclidic impurities were observed. Using the Clinical Trials Network anthropomorphic chest phantom, SPECT/CT images were acquired. Medium energy (ME) SPECT collimation was found to provide the best image quality from the primary 185 keV gamma emission of 67Cu. Reconstructed images of 67Cu were similar in quality to images acquired using 177Lu. Recovery coefficients were calculated and compared against quantitative images of 99mTc, 177Lu, and 64Cu within the same anthropomorphic chest phantom. Production and clinical imaging of 67Cu appears feasible, and future studies investigating the therapeutic efficacy of 67Cu-based radiopharmaceuticals are warranted.
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Affiliation(s)
- Michael J Merrick
- Department of Radiology, University of Iowa, Iowa City, IA, United States of America. Department of Biomedical Engineering, University of Iowa, Iowa City, IA, United States of America
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Hänscheid H, Hartrampf PE, Schirbel A, Buck AK, Lapa C. Intraindividual comparison of [ 177Lu]Lu-DOTA-EB-TATE and [ 177Lu]Lu-DOTA-TOC. Eur J Nucl Med Mol Imaging 2021; 48:2566-2572. [PMID: 33452632 PMCID: PMC8241641 DOI: 10.1007/s00259-020-05177-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 12/20/2020] [Indexed: 11/04/2022]
Abstract
Purpose The radiolabelled somatostatin analogue [177Lu]Lu-DOTA-EB-TATE binds to albumin via Evans blue, thereby increasing the residence time in the blood and potentially allowing more therapeutic agent to be absorbed into the target tissue during peptide receptor radionuclide therapy. It was tested in selected patients whether the substance is superior to [177Lu]Lu-DOTA-TOC. Methods Activity kinetics in organs and tumours after [177Lu]Lu-DOTA-EB-TATE and [177Lu]Lu-DOTA-TOC were compared intraindividually in five patients with progressive somatostatin receptor-positive disease scheduled for radionuclide therapy. Results In comparison to [177Lu]Lu-DOTA-TOC, tumour doses per administered activity were higher for [177Lu]Lu-DOTA-EB-TATE in 4 of 5 patients (median ratio: 1.7; range: 0.9 to 3.9), kidney doses (median ratio: 3.2; range: 1.6 to 9.8) as well as spleen doses (median ratio: 4.7; range 1.2 to 6.2) in all patients, and liver doses in 3 of 4 evaluable patients (median ratio: 4.0; range: 0.7 to 4.9). The tumour to critical organs absorbed dose ratios were higher after [177Lu]Lu-DOTA-TOC in 4 of 5 patients. Conclusions Prior to a treatment with [177Lu]Lu-DOTA-EB-TATE, it should be assessed individually whether the compound is superior to established substances.
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Affiliation(s)
- Heribert Hänscheid
- Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany.
| | - Philipp E Hartrampf
- Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Andreas Schirbel
- Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Andreas K Buck
- Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Constantin Lapa
- Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Str. 6, 97080, Würzburg, Germany.,Department of Nuclear Medicine, University Hospital Augsburg, Augsburg, Germany
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