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Kim TP, Gandhi RT, Tolakanahalli R, Herrera R, Chuong MD, Gutierrez AN, Alvarez D. Establishing Updated Safety Standards for Independent 99mTc-MAA SPECT/CT Treatment Planning in Radioembolization. Int J Radiat Oncol Biol Phys 2024; 119:1285-1296. [PMID: 38925768 DOI: 10.1016/j.ijrobp.2023.12.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 12/08/2023] [Accepted: 12/30/2023] [Indexed: 06/28/2024]
Abstract
PURPOSE Significant improvements within radioembolization imaging and dosimetry permit the development of an accurate and personalized pretreatment plan using technetium 99m-labeled macroaggregated albumin (99mTc-MAA) and single-photon emission computed tomography (SPECT) combined with anatomical CT (SPECT/CT). Despite these potential advantages, the clinical transition to pretreatment protocols with SPECT/CT is hindered by their unknown safety constraints. This study aimed to address this issue by establishing novel dose limits for 99mTc-MAA SPECT/CT to enable quantitative pretreatment planning. METHODS AND MATERIALS Stratification criteria to determine images most viable for dosimetry analysis were created from a cohort of 85 patients. SPECT/CT, cone beam CT, and activity calculations derived from the local deposition method were used to create an accurate pretreatment protocol. Planar and SPECT/CT images were compared using linear regression and modified Bland-Altman analyses to convert accepted planar dose limits to SPECT/CT. To validate these new dose limits, activity calculations based on SPECT/CT were compared with those calculated with the body surface area and planar methods for three treatment plans. RESULTS A total of 38 of 85 patients were deemed viable for dosimetry analysis. SPECT yielded greater lung shunt fractions (LSFs) than planar imaging when LSFs were <4.89%, whereas SPECT yielded lower LSFs than planar imaging when LSFs were >4.89%. Planar to SPECT/CT dose conversions were 0.76×, 0.70×, and 0.55× for the whole liver, normal liver, and lungs, respectively. Patients with SPECT LSFs ≤4.89% were safely treated with the direct application of planar lung dose limits. Activity calculations with the newly established SPECT/CT dose limits were greater than those of the body surface area method by a median range of 33.1% to 61.9% and were lower than planar-based activity calculations by a median range of 12.5% to 13.7% for the whole liver and by 29.4% to 32.2% for the normal liver. CONCLUSIONS This study demonstrated a safe method for translating dose limits from 99mTc-MAA planar imaging to SPECT/CT. A robust pretreatment protocol was further developed guided by the current knowledge in the field. Established SPECT/CT dose limits safely treated 97.5% of patients and permitted the application of independent pretreatment planning with 99mTc-MAA SPECT/CT.
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Affiliation(s)
| | - Ripal T Gandhi
- Radiation Oncology Department, Miami Cancer Institute, Miami, Florida; Interventional Radiology Department, Miami Cardiac and Vascular Institute, Miami, Florida
| | | | - Robert Herrera
- Radiation Oncology Department, Miami Cancer Institute, Miami, Florida
| | - Michael D Chuong
- Radiation Oncology Department, Miami Cancer Institute, Miami, Florida
| | | | - Diane Alvarez
- Radiation Oncology Department, Miami Cancer Institute, Miami, Florida
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Kovan B, Denizmen D, Civan C, Kuyumcu S, Isik EG, Has Simsek D, Ozkan ZG, Poyanli A, Demir B, Sanli Y. Influence of Early Versus Delayed Hepatic Artery Perfusion Scan on 90Y Selective Internal Radiation Therapy Planning. Cancer Biother Radiopharm 2024; 39:330-336. [PMID: 38265813 DOI: 10.1089/cbr.2023.0149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024] Open
Abstract
Purpose: This study evaluated the effect of an increase in the time interval between hepatic intra-arterial injection of 99mTc-macroaggregated albumin (MAA) and hepatic artery perfusion scintigraphy (HAPS) on the lung shunt fraction (LSF) and perfused volume (PV) calculations in the treatment planning of selective internal radiation therapy (SIRT). Methods: The authors enrolled 51 HAPS sessions from 40 patients diagnosed with primary or metastatic liver malignancy. All patients underwent scan at the first and fourth hour after hepatic arterial injection of 99mTc-MAA. Based on single-photon emission computed tomography images, LSF values were measured from each patient's first and fourth hour images. PV1 and PV4 were also calculated based on three-dimensional images using 5% and 10% cutoff threshold values and compared with each other. Results: The authors found that the median of LSF4 was statistically significantly higher than LSF1 (3.05 vs. 4.14, p ≤ 0.01). There was no statistically significant difference between PV1 and PV4 on the 10% (p = 0.72) thresholds. Conclusions: LSF values can be overestimated in case of delayed HAPS, potentially leading to treatment cancellation due to incorrectly high results in patients who could benefit from SIRT. Threshold-based PV values do not significantly change over time; nevertheless, keeping the short interval time would be safer.
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Affiliation(s)
- Bilal Kovan
- Department of Nuclear Medicine, Istanbul Faculty of Medicine, Istanbul University, Fatih/İstanbul, Turkey
| | - Dilara Denizmen
- Department of Nuclear Medicine, Istanbul Faculty of Medicine, Istanbul University, Fatih/İstanbul, Turkey
| | - Caner Civan
- Department of Nuclear Medicine, Istanbul Faculty of Medicine, Istanbul University, Fatih/İstanbul, Turkey
| | - Serkan Kuyumcu
- Department of Nuclear Medicine, Istanbul Faculty of Medicine, Istanbul University, Fatih/İstanbul, Turkey
| | - Emine Goknur Isik
- Department of Nuclear Medicine, Istanbul Faculty of Medicine, Istanbul University, Fatih/İstanbul, Turkey
| | - Duygu Has Simsek
- Department of Nuclear Medicine, Istanbul Faculty of Medicine, Istanbul University, Fatih/İstanbul, Turkey
| | - Zeynep Gozde Ozkan
- Department of Nuclear Medicine, Istanbul Faculty of Medicine, Istanbul University, Fatih/İstanbul, Turkey
| | - Arzu Poyanli
- Department of Radiology, Istanbul Faculty of Medicine, Istanbul University, Fatih/İstanbul, Turkey
| | - Bayram Demir
- Department of Physics, Faculty of Science, Istanbul University, Fatih/İstanbul, Turkey
| | - Yasemin Sanli
- Department of Nuclear Medicine, Istanbul Faculty of Medicine, Istanbul University, Fatih/İstanbul, Turkey
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Gamero Kubota P, Molvar C, Wagner R, Allam E, Halama J, James JR. Implications of lung shunt fraction calculation discrepancy in Yttrium-90 radioembolization treatment from 2D planar vs 3D single photon emission CT imaging. BJR Case Rep 2024; 10:uaae016. [PMID: 38854889 PMCID: PMC11162746 DOI: 10.1093/bjrcr/uaae016] [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: 02/20/2024] [Revised: 05/21/2024] [Accepted: 05/23/2024] [Indexed: 06/11/2024] Open
Abstract
The safety and efficacy of Yttrium-90 (Y-90) radio-embolization therapy is partly dependent on the lung shunt fraction (LSF). There may be a notable disparity between LSF when calculated using 2D planar imaging vs 3D single photon emission CT (SPECT); this can affect the total allowable Y-90 dose delivered and therefore change the effectiveness of the procedure. The case presented demonstrates an 81% decrease in LSF when calculated by SPECT as compared to 2D planar imaging. This case highlights the importance of considering the imaging technique and the potential discrepancies that can arise between planar and SPECT imaging in LSF assessment.
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Affiliation(s)
- Paula Gamero Kubota
- Department of Radiology and Medical Imaging, Loyola University School of Medicine, Maywood, IL60153, United States
| | - Christopher Molvar
- Department of Radiology and Medical Imaging, Loyola University School of Medicine, Maywood, IL60153, United States
| | - Robert Wagner
- Department of Radiology and Medical Imaging, Loyola University School of Medicine, Maywood, IL60153, United States
| | - Emad Allam
- Department of Radiology and Medical Imaging, Loyola University School of Medicine, Maywood, IL60153, United States
| | - James Halama
- Department of Radiology and Medical Imaging, Loyola University School of Medicine, Maywood, IL60153, United States
| | - Judy R James
- Department of Radiology and Medical Imaging, Loyola University School of Medicine, Maywood, IL60153, United States
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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.
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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
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Yeyin N, Kesmezacar FF, Tunçman D, Demir Ö, Uslu-Beşli L, Günay O, Demir M. Hepatopulmonary Shunt Ratio Verification Model for Transarterial Radioembolization. Curr Radiopharm 2024; 17:276-284. [PMID: 38288829 DOI: 10.2174/0118744710284130240108053733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 12/10/2023] [Accepted: 12/26/2023] [Indexed: 07/23/2024]
Abstract
INTRODUCTION The most important toxicity of transarterial radioembolization therapy applied in liver malignancies is radiation pneumonitis and fibrosis due to hepatopulmonary shunt of Yttrium-90 (90Y) microspheres. Currently, Technetium-99m macroaggregated albumin (99mTc-MAA) scintigraphic images are used to estimate lung shunt fraction (LSF) before treatment. The aim of this study was to create a phantom to calculate exact LFS rates according to 99mTc activities in the phantom and to compare these rates with LSF values calculated from scintigraphic images. MATERIALS AND METHODS A 3D-printed lung and liver phantom containing two liver tumors was developed from Polylactic Acid (PLA) material, which is similar to the normal-sized human body in terms of texture and density. Actual %LSFs were calculated by filling phantoms and tumors with 99mTc radionuclide. After the phantoms were placed in the water tank made of plexiglass material, planar, SPECT, and SPECT/CT images were obtained. The actual LSF ratio calculated from the activity amounts filled into the phantom was used for the verification of the quantification of scintigraphic images and the results obtained by the Simplicity90YTM method. RESULTS In our experimental model, LSFs calculated from 99mTc activities filled into the lungs, normal liver, small tumor, and large tumor were found to be 0%, 6.2%, 10.8%, and 16.9%. According to these actual LSF values, LSF values were calculated from planar, SPECT/CT (without attenuation correction), and SPECT/CT (with both attenuation and scatter correction) scintigraphic images of the phantom. In each scintigraphy, doses were calculated for lung, small tumor, large tumor, normal liver, and Simplicity90YTM. The doses calculated from planar and SPECT/CT (NoAC+NoSC) images were found to be higher than the actual doses. The doses calculated from SPECT/CT (with AC+with SC) images and Simplicity90YTM were found to be closer to the real dose values. CONCLUSION LSF is critical in dosimetry calculations of 90Y microsphere therapy. The newly introduced hepatopulmonary shunt phantom in this study is suitable for LSF verification for all models/brands of SPECT and SPECT/CT devices.
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Affiliation(s)
- Nami Yeyin
- Department of Nuclear Medicine, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Fatih/Istanbul, Turkey
| | | | - Duygu Tunçman
- Vocational School of Health Service, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Özge Demir
- Department of Chemical Engineering, Engineering Faculty, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Lebriz Uslu-Beşli
- Department of Nuclear Medicine, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Fatih/Istanbul, Turkey
| | - Osman Günay
- Department of Biomedical Engineering, Faculty of Electrical and Electronics Engineering, Yıldız Technical University, Istanbul, Turkey
| | - Mustafa Demir
- Department of Nuclear Medicine, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Fatih/Istanbul, Turkey
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Vergnaud L, Robert A, Baudier T, Parisse-Di Martino S, Boissard P, Rit S, Badel JN, Sarrut D. Dosimetric impact of 3D motion-compensated SPECT reconstruction for SIRT planning. EJNMMI Phys 2023; 10:8. [PMID: 36749446 PMCID: PMC9905464 DOI: 10.1186/s40658-023-00525-y] [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] [Received: 10/24/2022] [Accepted: 01/11/2023] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND In selective internal radiation therapy, 99mTc SPECT images are used to optimize patient treatment planning, but they are affected by respiratory motion. In this study, we evaluated on patient data the dosimetric impact of motion-compensated SPECT reconstruction on several volumes of interest (VOI), on the tumor-to-normal liver (TN) ratio and on the activity to be injected. METHODS Twenty-nine patients with liver cancer or hepatic metastases treated by radioembolization were included in this study. The biodistribution of 90Y is assumed to be the same as that of 99mTc when predictive dosimetry is implemented. A total of 31 99mTc SPECT images were acquired and reconstructed with two methods: conventional OSEM (3D) and motion-compensated OSEM (3Dcomp). Seven VOI (liver, lungs, tumors, perfused liver, hepatic reserve, healthy perfused liver and healthy liver) were delineated on the CT or obtained by thresholding SPECT images followed by Boolean operations. Absorbed doses were calculated for each reconstruction using Monte Carlo simulations. Percentages of dose difference (PDD) between 3Dcomp and 3D reconstructions were estimated as well as the relative differences for TN ratio and activities to be injected. The amplitude of movement was determined with local rigid registration of the liver between the 3Dcomp reconstructions of the extreme phases of breathing. RESULTS The mean amplitude of the liver was 9.5 ± 2.7 mm. Medians of PDD were closed to zero for all VOI except for lungs (6.4%) which means that the motion compensation overestimates the absorbed dose to the lungs compared to the 3D reconstruction. The smallest lesions had higher PDD than the largest ones. Between 3D and 3Dcomp reconstructions, means of differences in lung dose and TN ratio were not statistically significant, but in some cases these differences exceed 1 Gy (4/31) and 8% (2/31). The absolute differences in activity were on average 3.1% ± 5.1% and can reach 22.8%. CONCLUSION The correction of respiratory motion mainly impacts the lung and tumor doses but only for some patients. The largest dose differences are observed for the smallest lesions.
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Affiliation(s)
- Laure Vergnaud
- CREATIS; CNRS UMR 5220; INSERM U 1044; Université de Lyon; INSA-Lyon, Université Lyon 1, Lyon, France. .,Centre de Lutte Contre Le Cancer Léon Bérard, Lyon, France.
| | - Antoine Robert
- grid.7849.20000 0001 2150 7757CREATIS; CNRS UMR 5220; INSERM U 1044; Université de Lyon; INSA-Lyon, Université Lyon 1, Lyon, France
| | - Thomas Baudier
- grid.7849.20000 0001 2150 7757CREATIS; CNRS UMR 5220; INSERM U 1044; Université de Lyon; INSA-Lyon, Université Lyon 1, Lyon, France ,grid.418116.b0000 0001 0200 3174Centre de Lutte Contre Le Cancer Léon Bérard, Lyon, France
| | | | - Philippe Boissard
- grid.418116.b0000 0001 0200 3174Centre de Lutte Contre Le Cancer Léon Bérard, Lyon, France
| | - Simon Rit
- grid.7849.20000 0001 2150 7757CREATIS; CNRS UMR 5220; INSERM U 1044; Université de Lyon; INSA-Lyon, Université Lyon 1, Lyon, France
| | - Jean-Noël Badel
- grid.418116.b0000 0001 0200 3174Centre de Lutte Contre Le Cancer Léon Bérard, Lyon, France
| | - David Sarrut
- grid.7849.20000 0001 2150 7757CREATIS; CNRS UMR 5220; INSERM U 1044; Université de Lyon; INSA-Lyon, Université Lyon 1, Lyon, France ,grid.418116.b0000 0001 0200 3174Centre de Lutte Contre Le Cancer Léon Bérard, Lyon, France
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Kokabi N, Arndt-Webster L, Chen B, Brandon D, Sethi I, Davarpanahfakhr A, Galt J, Elsayed M, Bercu Z, Cristescu M, Kappadath SC, Schuster DM. Voxel-based dosimetry predicting treatment response and related toxicity in HCC patients treated with resin-based Y90 radioembolization: a prospective, single-arm study. Eur J Nucl Med Mol Imaging 2023; 50:1743-1752. [PMID: 36650357 PMCID: PMC10119065 DOI: 10.1007/s00259-023-06111-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 01/05/2023] [Indexed: 01/19/2023]
Abstract
BACKGROUND There is an increasing body of evidence indicating Y90 dose thresholds for tumor response and treatment-related toxicity. These thresholds are poorly studied in resin Y90, particularly in hepatocellular carcinoma (HCC). PURPOSE To evaluate the efficacy of prospective voxel-based dosimetry for predicting treatment response and adverse events (AEs) in patients with HCC undergoing resin-based Y90 radioembolization. MATERIALS AND METHODS This correlative study was based on a prospective single-arm clinical trial (NCT04172714), which evaluated the efficacy of low/scout (555 MBq) activity of resin-based Y90 for treatment planning. Partition model was used with goal of tumor dose (TD) > 200 Gy and non-tumoral liver dose (NTLD) < 70 Gy for non-segmental therapies. Single compartment dose of 200 Gy was used for segmentectomies. Prescribed Y90 activity minus scout activity was administered for therapeutic Y90 followed by Y90-PET/CT. Sureplan® (MIM Software, Cleveland, OH) was used for dosimetry analysis. Treatment response was evaluated at 3 and 6 months. Receiver operating characteristic curve determined TD response threshold for objective response (OR) and complete response (CR) as well as non-tumor liver dose (NTLD) threshold that predicted AEs. RESULTS N = 30 patients were treated with 33 tumors (19 segmental and 14 non-segmental). One patient died before the first imaging, and clinical follow-up was excluded from this analysis. Overall, 26 (81%) of the tumors had an OR and 23 (72%) had a CR. A mean TD of 253 Gy predicted an OR with 92% sensitivity and 83% specificity (area under the curve (AUC = 0.929, p < 0.001). A mean TD of 337 Gy predicted a CR with 83% sensitivity and 89% specificity (AUC = 0.845, p < 0.001). A mean NTLD of 81 and 87 Gy predicted grade 3 AEs with 100% sensitivity and 100% specificity in the non-segmental cohort at 3- and 6-month post Y90, respectively. CONCLUSION In patients with HCC undergoing resin-based Y90, there are dose response and dose toxicity thresholds directly affecting outcomes. CLINICAL TRIAL NUMBER NCT04172714.
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Affiliation(s)
- Nima Kokabi
- Division of Interventional Radiology and Image-Guided Medicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA.
| | - Linzi Arndt-Webster
- Division of Interventional Radiology, Department of Radiology, Mount Sinai School of Medicine, New York, NY, USA
| | - Bernard Chen
- Division of Interventional Radiology, Department of Radiology, University of Texas at San Antonio, San Antonio, TX, USA
| | - David Brandon
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Ila Sethi
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Amir Davarpanahfakhr
- Division of Abdominal Imaging, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - James Galt
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Mohammad Elsayed
- Division of Interventional Radiology, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Zachary Bercu
- Division of Interventional Radiology and Image-Guided Medicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Mircea Cristescu
- Division of Interventional Radiology, Department of Radiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - S Cheenu Kappadath
- Division of Interventional Radiology, Department of Radiology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - David M Schuster
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA
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Young S, Flanagan S, D'Souza D, Todatry S, Ragulojan R, Sanghvi T, Golzarian J. Lung shunt fraction calculations before Y-90 transarterial radioembolization: Comparison of accuracy and clinical significance of planar scintigraphy and SPECT/CT. Diagn Interv Imaging 2023; 104:185-191. [PMID: 36604211 DOI: 10.1016/j.diii.2022.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 12/02/2022] [Accepted: 12/16/2022] [Indexed: 01/04/2023]
Abstract
PURPOSE To determine the accuracy and clinical significance of planar scintigraphy lung shunt fraction (PLSF) and single-photon emission computerized tomography (SPECT) computed tomography (CT) lung shunt fraction (SLSF) before Y-90 transarterial radioembolization. MATERIALS AND METHODS Seventy patients (46 men, 24 women; mean age, 64 ± 9.5 [SD] years) who underwent 83 treatments with Y-90 transarterial radioembolization for primary or secondary malignancies of the liver with a PLSF ≥ 7.5% were retrospectively evaluated. The patients mapping technetium 99 m (Tc-99 m) macroaggregated albumin (MAA) PLSF and SLSF were calculated and compared to the post Y-90 delivery SLSF. A model using modern dose thresholds was created to identify patients who would require dose reduction due to a lung dose ≥ 30 Gy, with patients who required >50% dose reduction considered to be delivery cancelations. RESULTS A significant difference was found between mean PLSF (14.7 ± 11.6 [SD]%; range: 7.5-84.1%) and mean SLSF (8.7 ± 8.5 [SD]%; range: 1.7-73.5) (P < 0.001). The mean realized LSF (7.1 ± 3 [SD]%; range:1.5-17.6) was significantly less than the PLSF (P <0.001) but not the SLSF (P = 0.07). PLSF significantly overestimated the realized LSF by more than the SLSF (8.5 ± 5.3 [SD] % [range: -0.1-21.7] vs. 0.8 ± 3.6 [SD] % [range: -5-13.2], respectively) (P < 0.001). Based on the clinical significance model, 20 patients (20/83, 24.1%) would have required dose reduction or cancelation when using PLSF but would not require even a dose reduction when using the SLSF. Significantly more deliveries would have been be canceled if PLSF was used as compared to SLSF (22/83 [26.5%] vs. 6/83 [7.2%], respectively) (P < 0.001). CONCLUSION SLSF is significantly more accurate at predicting realized LSF than PLSF and this difference is of clinical significance in a number of patients with a PLSF ≥ 7.5%.
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Affiliation(s)
- Shamar Young
- Department of Medical Imaging, Division of Interventional Radiology, University of Arizona, Tucson, AZ 85724, USA
| | - Siobhan Flanagan
- Department of Radiology, Division of Interventional Radiology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Donna D'Souza
- Department of Radiology, Division of Interventional Radiology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Soorya Todatry
- Department of Radiology, Division of Interventional Radiology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Ranjan Ragulojan
- Department of Radiology, Division of Interventional Radiology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Tina Sanghvi
- Department of Radiology, Arizona Veterans Administration Hospital, Minneapolis, MN 55417, USA
| | - Jafar Golzarian
- Department of Radiology, Division of Interventional Radiology, University of Minnesota, Minneapolis, MN 55455, USA
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Abuqbeitah M, Akdağ ÖT, Demir M, Asa S, Sönmezoğlu K. Simplification of dosimetry in 90Y-radioembolization therapy by dual planar images. BMC Cancer 2022; 22:1288. [PMID: 36482312 PMCID: PMC9733257 DOI: 10.1186/s12885-022-10392-y] [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] [Received: 01/19/2021] [Accepted: 10/18/2021] [Indexed: 12/13/2022] Open
Abstract
AIM The purpose was to provide a practical and effective method for performing reliable 90Y dosimetry based on 99mTc-MAA and SPEC/CT. The impact of scatter correction (SC) and attenuation correction (AC) on the injected 90Y activity, lung shunt fraction (LSF) and the delivered dose to lung and liver compartments was investigated within the scope of the study. MATERIAL AND METHODS Eighteen eligible patients (F: 3, M: 15) were subjected to 90Y therapy. 99mTc-MAA (111-222 MBq) was injected into the targeted liver, followed by whole-body scan (WBS) with peak-window at 140 keV (15% width) and one down-scatter window. SPECT/CT scan was subsequently acquired encompassing lung and liver regions. The LSFs were fashioned from standard WBS LSFwb (St), scatter corrected WBS LSFwb (Sc), only scatter corrected SPECT LSFspect (NoAC-SC) and SPECT/CT with attenuation and scatter correction LSFspect (AC-SC). The absorbed doses that would be delivered to tumor and injected healthy liver were estimated using different calculation modes involving AC-SC (SPECT/CT), NoAC-SC (SPECT), NoAC-NoSC+LSFwb (SC), AC-SC + LSFwb (St), and NoAC-NoSC+LSFwb (St). RESULTS The average deviations (range) in LSF values between standard LSFwb (St) and those from SPECT/CT (AC-SC), SPECT (NoAC-SC), and LSFwb (SC) were - 50% (- 29/- 71), - 32% (- 8/- 67), and - 45% (- 13/80), respectively. The suggested 90Y activity (GBq/Gy) was decreased within a range of 2-11%, 1-9%, and 2-7% by using LSFspect (AC-SC), LSFspect (NoAC-SC), and LSFwb (SC), respectively. Overall, two-sample t-test yielded no statistically significant difference (p < 0.05) in the absorbed doses to tumor and injected healthy liver between AC-SC (SPECT) and the rest of approaches with/and without AC and SC. However, a statistically significant difference (p < 0.05) was demonstrated in the lung shunt fractions and lung doses due to AC and SC. The LSFs from scatter corrected planar images LSFwb (SC) exhibited well agreement (R2 = 0.92) with SPECT/CT (AC-SC) and there was no statistically significant difference (Pvalue > 0.05) between both methods. CONCLUSION It was deduced that SPECT/CT with attenuation and scatter correction plays a crucial role in the measurements of lung shunt fraction and dose as well as the total number of 90Y treatments. However, the absorbed dose to tumors and injected healthy liver was minimally affected by AC and SC. Besides, a good agreement was observed between LSF datasets from SPECT/CT versus scatter corrected WBS that can be alternatively and effectively used in 90Y dosimetry.
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Affiliation(s)
- Mohammad Abuqbeitah
- Department of Nuclear Medicine, Istanbul University - Cerrahpasa, Cerrahpasa Faculty of Medicine, Istanbul, Turkey.
| | - Özgür Taylan Akdağ
- Department of Nuclear Medicine, Istanbul University - Cerrahpasa, Cerrahpasa Faculty of Medicine, Istanbul, Turkey
| | - Mustafa Demir
- Department of Nuclear Medicine, Istanbul University - Cerrahpasa, Cerrahpasa Faculty of Medicine, Istanbul, Turkey
| | - Sertaç Asa
- Department of Nuclear Medicine, Istanbul University - Cerrahpasa, Cerrahpasa Faculty of Medicine, Istanbul, Turkey
| | - Kerim Sönmezoğlu
- Department of Nuclear Medicine, Istanbul University - Cerrahpasa, Cerrahpasa Faculty of Medicine, Istanbul, Turkey
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Lopez BP, Mahvash A, Long JP, Lam MGEH, Kappadath SC. Factors modulating 99m Tc-MAA planar lung dosimetry for 90 Y radioembolization. J Appl Clin Med Phys 2022; 23:e13734. [PMID: 35906892 PMCID: PMC9797182 DOI: 10.1002/acm2.13734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/30/2022] [Accepted: 07/07/2022] [Indexed: 01/01/2023] Open
Abstract
PURPOSE To investigate the accuracy and biases of predicted lung shunt fraction (LSF) and lung dose (LD) calculations via 99m Tc-macro-aggregated albumin (99m Tc-MAA) planar imaging for treatment planning of 90 Y-microsphere radioembolization. METHODS AND MATERIALS LSFs in 52 planning and LDs in 44 treatment procedures were retrospectively calculated, in consecutive radioembolization patients over a 2 year interval, using 99m Tc-MAA planar and SPECT/CT imaging. For each procedure, multiple planar LSFs and LDs were calculated using different: (1) contours, (2) views, (3) liver 99m Tc-MAA shine-through compensations, and (4) lung mass estimations. The accuracy of each planar-based LSF and LD methodology was determined by calculating the median (range) absolute difference from SPECT/CT-based LSF and LD values, which have been demonstrated in phantom and patient studies to more accurately and reliably quantify the true LSF and LD values. RESULTS Standard-of-care LSF using geometric mean of lung and liver contours had median (range) absolute over-estimation of 4.4 percentage points (pp) (0.9 to 11.9 pp) from SPECT/CT LSF. Using anterior views only decreased LSF errors (2.4 pp median, -1.1 to +5.7 pp range). Planar LD over-estimations decreased when using single-view versus geometric-mean LSF (1.3 vs. 2.6 Gy median and 7.2 vs. 18.5 Gy maximum using 1000 g lung mass) but increased when using patient-specific versus standard-man lung mass (2.4 vs. 1.3 Gy median and 11.8 vs. 7.2 Gy maximum using single-view LSF). CONCLUSIONS Calculating planar LSF from lung and liver contours of a single view and planar LD using that same LSF and 1000 g lung mass was found to improve accuracy and minimize bias in planar lung dosimetry.
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Affiliation(s)
- Benjamin P. Lopez
- Department of Imaging PhysicsUniversity of Texas MD Anderson Cancer CenterHoustonTexasUSA
- University of Texas MD Anderson Cancer Center UT Health Houston Graduate School of Biomedical SciencesHoustonTexasUSA
| | - Armeen Mahvash
- Department of Interventional RadiologyUniversity of Texas MD Anderson Cancer CenterHoustonTexasUSA
| | - James P. Long
- Department of BiostatisticsUniversity of Texas MD Anderson Cancer CenterHoustonTexasUSA
| | - Marnix G. E. H. Lam
- Department of Radiology and Nuclear MedicineUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - S. Cheenu Kappadath
- Department of Imaging PhysicsUniversity of Texas MD Anderson Cancer CenterHoustonTexasUSA
- University of Texas MD Anderson Cancer Center UT Health Houston Graduate School of Biomedical SciencesHoustonTexasUSA
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11
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Prediction of Lung Shunt Fraction for Yttrium-90 Treatment of Hepatic Tumors Using Dynamic Contrast Enhanced MRI with Quantitative Perfusion Processing. Tomography 2022; 8:2687-2697. [PMID: 36412683 PMCID: PMC9680251 DOI: 10.3390/tomography8060224] [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] [Received: 09/20/2022] [Revised: 10/27/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022] Open
Abstract
There is no noninvasive method to estimate lung shunting fraction (LSF) in patients with liver tumors undergoing Yttrium-90 (Y90) therapy. We propose to predict LSF from noninvasive dynamic contrast enhanced (DCE) MRI using perfusion quantification. Two perfusion quantification methods were used to process DCE MRI in 25 liver tumor patients: Kety's tracer kinetic modeling with a delay-fitted global arterial input function (AIF) and quantitative transport mapping (QTM) based on the inversion of transport equation using spatial deconvolution without AIF. LSF was measured on SPECT following Tc-99m macroaggregated albumin (MAA) administration via hepatic arterial catheter. The patient cohort was partitioned into a low-risk group (LSF ≤&nbsp;10%) and a high-risk group (LSF >&nbsp;10%). Results: In this patient cohort, LSF was positively correlated with QTM velocity |u| (r = 0.61, F = 14.0363, p = 0.0021), and no significant correlation was observed with Kety's parameters, tumor volume, patient age and gender. Between the low LSF and high LSF groups, there was a significant difference for QTM |u| (0.0760 ± 0.0440 vs. 0.1822 ± 0.1225 mm/s, p = 0.0011), and Kety's Ktrans (0.0401 ± 0.0360 vs 0.1198 ± 0.3048, p = 0.0471) and Ve&nbsp;(0.0900 ± 0.0307 vs. 0.1495 ± 0.0485, p = 0.0114). The area under the curve (AUC) for distinguishing between low LSF and high LSF was 0.87 for |u|, 0.80 for Ve and 0.74 for Ktrans. Noninvasive prediction of LSF is feasible from DCE MRI with QTM velocity postprocessing.
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12
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Sharma NK, Kappadath SC, Chuong M, Folkert M, Gibbs P, Jabbour SK, Jeyarajah DR, Kennedy A, Liu D, Meyer JE, Mikell J, Patel RS, Yang G, Mourtada F. The American Brachytherapy Society consensus statement for permanent implant brachytherapy using Yttrium-90 microsphere radioembolization for liver tumors. Brachytherapy 2022; 21:569-591. [PMID: 35599080 PMCID: PMC10868645 DOI: 10.1016/j.brachy.2022.04.004] [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: 12/20/2021] [Revised: 03/25/2022] [Accepted: 04/14/2022] [Indexed: 11/02/2022]
Abstract
PURPOSE To develop a multidisciplinary consensus for high quality multidisciplinary implementation of brachytherapy using Yttrium-90 (90Y) microspheres transarterial radioembolization (90Y TARE) for primary and metastatic cancers in the liver. METHODS AND MATERIALS Members of the American Brachytherapy Society (ABS) and colleagues with multidisciplinary expertise in liver tumor therapy formulated guidelines for 90Y TARE for unresectable primary liver malignancies and unresectable metastatic cancer to the liver. The consensus is provided on the most recent literature and clinical experience. RESULTS The ABS strongly recommends the use of 90Y microsphere brachytherapy for the definitive/palliative treatment of unresectable liver cancer when recommended by the multidisciplinary team. A quality management program must be implemented at the start of 90Y TARE program development and follow-up data should be tracked for efficacy and toxicity. Patient-specific dosimetry optimized for treatment intent is recommended when conducting 90Y TARE. Implementation in patients on systemic therapy should account for factors that may enhance treatment related toxicity without delaying treatment inappropriately. Further management and salvage therapy options including retreatment with 90Y TARE should be carefully considered. CONCLUSIONS ABS consensus for implementing a safe 90Y TARE program for liver cancer in the multidisciplinary setting is presented. It builds on previous guidelines to include recommendations for appropriate implementation based on current literature and practices in experienced centers. Practitioners and cooperative groups are encouraged to use this document as a guide to formulate their clinical practices and to adopt the most recent dose reporting policies that are critical for a unified outcome analysis of future effectiveness studies.
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Affiliation(s)
- Navesh K Sharma
- Department of Radiation Oncology, Penn State Hershey School of Medicine, Hershey, PA
| | - S Cheenu Kappadath
- Department of Imaging Physics, UT MD Anderson Cancer Center, Houston, TX
| | - Michael Chuong
- Department of Radiation Oncology, Miami Cancer Institute, Miami, FL
| | - Michael Folkert
- Northwell Health Cancer Institute, Radiation Medicine at the Center for Advanced Medicine, New Hyde Park, NY
| | - Peter Gibbs
- Personalised Oncology Division, Walter and Eliza Hall Institute, Melbourne, Victoria, Australia
| | - Salma K Jabbour
- Rutgers Cancer Institute of New Jersey, Rutgers University, New Brunswick, NJ
| | | | | | - David Liu
- Vancouver General Hospital, Vancouver, British Columbia, Canada
| | | | | | - Rahul S Patel
- Icahn School of Medicine at Mount Sinai, New York, NY
| | - Gary Yang
- Loma Linda University, Loma Linda, CA
| | - Firas Mourtada
- Helen F. Graham Cancer Center & Research Institute, Christiana Care Health System, Newark, DE; Department of Radiation Oncology, Sidney Kimmel Cancer Center at Thomas Jefferson University, Philadelphia, PA.
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Torkian P, Ragulojan R, J. Woodhead G, D'Souza D, Flanagan S, Golzarian J, Young S. Lung shunt fraction quantification methods in radioembolization: What you need to know. Br J Radiol 2022; 95:20220470. [DOI: 10.1259/bjr.20220470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
In some patients undergoing radioembolization, lung toxicity is a limiting factor when calculating their dose. At the same time, it is known that the lung shunt fraction (LSF) is overestimated by the mapping exam. Furthermore, there are multiple methods to measure LSF. Planar measurement is both the most commonly utilized and easiest to perform, however new dosimetry software provides the ability to use more advanced 3D techniques. This paper reviews the different LSF calculation methods and elucidates the available data comparing the techniques, clinical relevance, and dose calculation.
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Affiliation(s)
- Pooya Torkian
- Department of Radiology, Vascular and Interventional Radiology, University of Minnesota, Minneapolis, United States
| | - Ranjan Ragulojan
- Department of Radiology, Vascular and Interventional Radiology, University of Minnesota, Minneapolis, United States
| | - Gregory J. Woodhead
- Department of Medical Imaging, University of Arizona, 1501 North Campbell Avenue, Tucson, United States
| | - Donna D'Souza
- Department of Radiology, Vascular and Interventional Radiology, University of Minnesota, Minneapolis, United States
| | - Siobhan Flanagan
- Department of Radiology, Vascular and Interventional Radiology, University of Minnesota, Minneapolis, United States
| | - Jafar Golzarian
- Department of Radiology, Vascular and Interventional Radiology, University of Minnesota, Minneapolis, United States
| | - Shamar Young
- Department of Medical Imaging, University of Arizona, 1501 North Campbell Avenue, Tucson, United States
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Using an Assumed Lung Mass Inaccurately Estimates the Lung Absorbed Dose in Patients Undergoing Hepatic 90Yttrium Radioembolization Therapy. Cardiovasc Intervent Radiol 2022; 45:1793-1800. [PMID: 35925379 DOI: 10.1007/s00270-022-03197-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 06/03/2022] [Indexed: 11/02/2022]
Abstract
RATIONALE Currently, the estimated absorbed radiation dose to the lung in 90Y radioembolization therapy is calculated using an assumed 1 kg lung mass for all patients. The aim of this study was to evaluate whether using a patient-specific lung mass measurement for each patient rather than a generic, assumed 1 kg lung mass would change the estimated lung absorbed dose. METHODS A retrospective analysis was performed on 68 patients who had undergone 90Y radioembolization therapy at our institution. Individualized lung volumes were measured manually on CT scans for each patient, and these volumes were used to calculate personalized lung masses. The personalized lung masses were used to recalculate the estimated lung absorbed dose from the 90Y therapy, and this dose was compared to the estimated lung absorbed dose calculated using an assumed 1 kg lung mass. RESULTS Patient-specific lung masses were significantly different from the generic 1 kg when compared individually for each patient (p < 0.0001). Median individualized lung mass was 0.71 (IQR: 0.59, 1.02) kg overall and was significantly different from the generic 1 kg lung mass for female patients [0.59 (0.50, 0.68) kg, (p < 0.0001)] but not for male patients [0.99 (0.71, 1.14) kg, (p = 0.24)]. Median estimated lung absorbed dose was 4.48 (2.38, 11.71) Gy using a patient-specific lung mass and 3.45 (1.81, 6.68) Gy when assuming a 1 kg lung mass for all patients. The estimated lung absorbed dose was significantly different using a patient-specific versus generic 1 kg lung mass when comparing the doses individually for each patient (p < 0.0001). The difference in the estimated lung absorbed dose between the patient-specific and generic 1 kg lung mass method was significant for female patients as a subgroup but not for male patients. CONCLUSIONS The current method of assuming a 1 kg lung mass for all patients inaccurately estimates the lung absorbed dose in 90Y radioembolization therapy. Using patient-specific lung masses resulted in estimated lung absorbed doses that were significantly different from those calculated using an assumed 1 kg lung mass for all patients. A personalized dosimetry method that includes individualized lung masses is necessary and can warrant a 90Y dose reduction in some patients with lung masses smaller than 1 kg. LEVEL OF EVIDENCE Level 3, Retrospective Study.
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15
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Pistone D, Italiano A, Auditore L, Mandaglio G, Campenní A, Baldari S, Amato E. Relevance of artefacts in 99mTc-MAA SPECT scans on pre-therapy patient-specific 90Y TARE internal dosimetry: a GATE Monte Carlo study. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac6b0f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 04/27/2022] [Indexed: 11/12/2022]
Abstract
Abstract
Objective. The direct Monte Carlo (MC) simulation of radiation transport exploiting morphological and functional tomographic imaging as input data is considered the gold standard for internal dosimetry in nuclear medicine, and it is increasingly used in studies regarding trans-arterial radio-embolization (TARE). However, artefacts affecting the functional scans, such as reconstruction artefacts and motion blurring, decrease the accuracy in defining the radionuclide distribution in the simulations and consequently lead to errors in absorbed dose estimations. In this study, the relevance of such artefacts in patient-specific three-dimensional MC dosimetry was investigated in three cases of 90Y TARE. Approach. The pre-therapy 99mTc MacroAggregate Albumin (Tc-MAA) SPECTs and CTs of patients were used as input for simulations performed with the GEANT4-based toolkit GATE. Several pre-simulation SPECT-masking techniques were implemented, with the aim of zeroing the decay probability in air, in lungs, or in the whole volume outside the liver. Main results. Increments in absorbed dose up to about +40% with respect to the native-SPECT simulations were found in liver-related volumes of interest (VOIs), depending on the masking procedure adopted. Regarding lungs-related VOIs, decrements in absorbed doses in right lung as high as −90% were retrieved. Significance. These results highlight the relevant influence of SPECT artefacts, if not properly treated, on dosimetric outcomes for 90Y TARE cases. Well-designed SPECT-masking techniques appear to be a promising way to correct for such misestimations.
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16
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McArdle N, Cournane S, McCavana J, Lucey J, León Vintró L. Development of a scatter correction technique for planar 99mTc-MAA imaging to improve accuracy in lung shunt fraction estimation. Phys Med 2022; 99:94-101. [PMID: 35665625 DOI: 10.1016/j.ejmp.2022.05.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 05/26/2022] [Accepted: 05/27/2022] [Indexed: 10/18/2022] Open
Abstract
PURPOSE Prior to 90Y selective internal radiation therapy (SIRT) treatment, 99mTc-MAA scintigraphy imaging is used in the estimation of the lung shunt fraction (LSF). Planar imaging is recommended for determining a LSF ratio. However, the estimate may be affected by scatter contributions, attenuation and respiratory motion. The objective of this study was to correct for the effects of scatter in the LSF, towards the determination of a more accurate estimation method of LSF derived from planar scintigraphy imaging, which is recommended by international guidelines. METHODS The open access SIMIND Monte Carlo modelling software was used to estimate an optimum scatter window (SW) for scatter correction. The uncertainties associated with scatter and scatter contributions from the liver on the LSF were evaluated using an anthropomorphic thorax phantom and a virtual Vox-Man phantom. A brief retrospective examination of patient scans and tumour location investigated the impact that the inclusion of the simulated scatter corrections had on the LSF estimation. RESULTS The percentage overestimation of the manufacturer recommended method of LSF estimation was 192%. SW corrections improved the uncertainty to within 19% for the range of known LSFs. Similar findings were observed for our patient and tumour location studies. CONCLUSION The incorporated scatter corrections can significantly improve the accuracy of the LSF estimation, thereby providing a robust gamma camera, patient and tumour depth specific correction which is easily implementable. This is supported by Monte Carlo, phantom and preliminary patient studies.
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Affiliation(s)
- Niamh McArdle
- St. Vincent's University Hospital, Ireland; University College Dublin, Ireland.
| | - Seán Cournane
- St. Vincent's University Hospital, Ireland; University College Dublin, Ireland
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Santoro M, Della Gala G, Paolani G, Zagni F, Strolin S, Civollani S, Calderoni L, Cappelli A, Mosconi C, Lodi Rizzini E, Tabacchi E, Morganti AG, Fanti S, Golfieri R, Strigari L. A novel tool for motion-related dose inaccuracies reduction in 99mTc-MAA SPECT/CT images for SIRT planning. Phys Med 2022; 98:98-112. [PMID: 35526374 DOI: 10.1016/j.ejmp.2022.04.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 04/05/2022] [Accepted: 04/27/2022] [Indexed: 12/19/2022] Open
Abstract
INTRODUCTION In Selective Internal Radiation Therapy (SIRT), 90Y is administered to primary/secondary hepatic lesions. An accurate pre-treatment planning using 99mTc-MAA SPECT/CT allows the assessment of its feasibility and of the activity to be injected. Unfortunately, SPECT/CT suffers from patient-specific respiratory motion which causes artifacts and absorbed dose inaccuracies. In this study, a data-driven solution was developed to correct the respiratory motion. METHODS The tool realigns the barycenter of SPECT projection images and shifts them to obtain a fine registration with the attenuation map. The tool was validated using a modified dynamic phantom with several breathing patterns. We compared the absorbed dose distributions derived from uncorrected(Dm)/corrected(Dc) images with static ones(Ds) in terms of γ-passing rates, 210 Gy isodose volumes, dose-volume histograms and percentage differences of mean doses (i.e., ΔD¯m and ΔD¯c, respectively). The tool was applied to twelve SIRT patients and the Bland-Altman analysis was performed on mean doses. RESULTS In the phantom study, the agreement between Dc and Ds was higher (γ-passing rates generally > 90%) than Dm and Ds. The isodose volumes in Dc were closer than Dm to Ds, with differences up to 10% and 30% respectively. A reduction from a median ΔD¯m = -19.3% to ΔD¯c = -0.9%, from ΔD¯m = -42.8% to ΔD¯c = -7.0% and from ΔD¯m = 1586% to ΔD¯c = 47.2% was observed in liver-, tumor- and lungs-like structures. The Bland-Altman analysis on patients showed variations (±50 Gy) and (±4 Gy) between D¯c and D¯m of tumor and lungs, respectively. CONCLUSION The proposed tool allowed the correction of 99mTc-MAA SPECT/CT images, improving the accuracy of the absorbed dose distribution.
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Affiliation(s)
- Miriam Santoro
- Medical Physics, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Giuseppe Della Gala
- Medical Physics, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Giulia Paolani
- Medical Physics, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Federico Zagni
- Medical Physics, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Silvia Strolin
- Medical Physics, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Simona Civollani
- Medical Physics, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Letizia Calderoni
- Nuclear Medicine Unit, IRCCS Azienda Ospedaliero, University of Bologna, 40138 Bologna, Italy
| | - Alberta Cappelli
- Department of Radiology, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Cristina Mosconi
- Department of Radiology, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Elisa Lodi Rizzini
- Radiation Oncology, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Elena Tabacchi
- Nuclear Medicine Unit, IRCCS Azienda Ospedaliero, University of Bologna, 40138 Bologna, Italy
| | | | - Stefano Fanti
- Nuclear Medicine Unit, IRCCS Azienda Ospedaliero, University of Bologna, 40138 Bologna, Italy
| | - Rita Golfieri
- Department of Radiology, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy
| | - Lidia Strigari
- Medical Physics, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy.
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Bertolet A, Wehrenberg-Klee E, Bobić M, Grassberger C, Perl J, Paganetti H, Schuemann J. Pre- and post-treatment image-based dosimetry in 90Y-microsphere radioembolization using the TOPAS Monte Carlo toolkit. Phys Med Biol 2021; 66:10.1088/1361-6560/ac43fd. [PMID: 34915451 PMCID: PMC8729171 DOI: 10.1088/1361-6560/ac43fd] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/16/2021] [Indexed: 12/31/2022]
Abstract
Objective. To evaluate the pre-treatment and post-treatment imaging-based dosimetry of patients treated with 90Y-microspheres, including accurate estimations of dose to tumor, healthy liver and lung. To do so, the Monte Carlo (MC) TOPAS platform is in this work extended towards its utilization in radionuclide therapy.Approach. Five patients treated at the Massachusetts General Hospital were selected for this study. All patients had data for both pre-treatment SPECT-CT imaging using 99mTc-MAA as a surrogate of the 90Y-microspheres treatment and SPECT-CT imaging immediately after the 90Y activity administration. Pre- and post-treatment doses were computed with TOPAS using the SPECT images to localize the source positions and the CT images to account for tissue inhomoegeneities. We compared our results with analytical calculations following the voxel-based MIRD scheme.Main results. TOPAS results largely agreed with the MIRD-based calculations in soft tissue regions: the average difference in mean dose to the liver was 0.14 Gy GBq-1(2.6%). However, dose distributions in the lung differed considerably: absolute differences in mean doses to the lung ranged from 1.2 to 6.3 Gy GBq-1and relative differences from 153% to 231%. We also found large differences in the intra-hepatic dose distributions between pre- and post-treatment imaging, but only limited differences in the pulmonary dose.Significance. Doses to lung were found to be higher using TOPAS with respect to analytical calculations which may significantly underestimate dose to the lung, suggesting the use of MC methods for 90Y dosimetry. According to our results, pre-treatment imaging may still be representative of dose to lung in these treatments.
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Affiliation(s)
- Alejandro Bertolet
- Department of Radiation Oncology, Massachusetts General Hospital
and Harvard Medical School, Boston, MA, USA
| | - Eric Wehrenberg-Klee
- Department of Radiology, Division of Interventional Radiology,
Massachusetts General Hospital, Boston, MA, USA
| | - Mislav Bobić
- Department of Radiation Oncology, Massachusetts General Hospital
and Harvard Medical School, Boston, MA, USA & Department of Physics, ETH
Zürich, Zürich, Switzerland
| | - Clemens Grassberger
- Department of Radiation Oncology, Massachusetts General Hospital
and Harvard Medical School, Boston, MA
| | - Joseph Perl
- SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Harald Paganetti
- Department of Radiation Oncology, Massachusetts General Hospital
and Harvard Medical School, Boston, MA, USA
| | - Jan Schuemann
- Department of Radiation Oncology, Massachusetts General Hospital
and Harvard Medical School, Boston, MA, USA
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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.
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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.
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20
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Kim SP, Juneau D, Cohalan C, Enger SA. Standardizing SPECT/CT dosimetry following radioembolization with yttrium-90 microspheres. EJNMMI Phys 2021; 8:71. [PMID: 34716850 PMCID: PMC8557238 DOI: 10.1186/s40658-021-00413-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 09/10/2021] [Indexed: 12/19/2022] Open
Abstract
Background Multiple post-treatment dosimetry methods are currently under investigation for Yttrium-90 (\documentclass[12pt]{minimal}
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\begin{document}$$^{90}\hbox {Y}$$\end{document}90Y) radioembolization. Within each methodology, a variety of dosimetric inputs exists that affect the final dose estimates. Understanding their effects is essential to facilitating proper dose analysis and crucial in the eventual standardization of radioembolization dosimetry. The purpose of this study is to investigate the dose differences due to different self-calibrations and mass density assignments in the non-compartmental and local deposition methods. A practical mean correction method was introduced that permits dosimetry in images where the quality is compromised by patient motion and partial volume effects. Methods Twenty-one patients underwent \documentclass[12pt]{minimal}
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\begin{document}$$^{90}\hbox {Y}$$\end{document}90Y radioembolization and were imaged with SPECT/CT. Five different self-calibrations (FOV, Body, OAR, Liverlung, and Liver) were implemented and dosimetrically compared. The non-compartmental and local deposition method were used to perform dosimetry based on either nominal- or CT calibration-based mass densities. A mean correction method was derived assuming homogeneous densities. Cumulative dose volume histograms, linear regressions, boxplots, and Bland Altman plots were utilized for analysis. Results Up to 270% weighted dose difference was found between self-calibrations with mean dose differences up to 50 Gy in the liver and 23 Gy in the lungs. Between the local deposition and non-compartmental methods, the liver and lung had dose differences within 0.71 Gy and 20 Gy, respectively. The local deposition method’s nominal and CT calibration-based mass density implementations dosimetric metrics were within 1.4% in the liver and 24% in the lungs. The mean lung doses calculated with the CT method were shown to be inflated. The mean correction method demonstrated that the corrected mean doses were greater by up to \documentclass[12pt]{minimal}
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\begin{document}$$\sim 5$$\end{document}∼5 Gy in the liver and lower by up to \documentclass[12pt]{minimal}
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\begin{document}$$\sim 12$$\end{document}∼12 Gy in the lungs. Conclusions The OAR calibration may be utilized as a potentially more accurate and precise self-calibration. The non-compartmental method was found more comparable to the local deposition method in organs that were more homogeneous in mass densities. Due to the potential for inflated lung mean doses, the non-compartmental and local deposition method implemented with nominal mass densities is recommended for more consistent dosimetric results. If patient motion and partial volume effects are present in the liver, our practical correction method will calculate more representative doses in images suboptimal for dosimetry.
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Affiliation(s)
- S Peter Kim
- Medical Physics Unit, McGill University, Montreal, Canada. .,Biological and Biomedical Engineering, McGill University, Montreal, Canada.
| | - Daniel Juneau
- Department of Medical Imaging, Centre Hospitalier de l'Université de Montréal, Montreal, Canada
| | - Claire Cohalan
- Department of Physics and Biomedical Engineering, Centre Hospitalier de l'Université de Montréal, Montreal, Canada
| | - Shirin A Enger
- Medical Physics Unit, McGill University, Montreal, Canada.,Biological and Biomedical Engineering, McGill University, Montreal, Canada.,Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Canada
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21
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Clinical and Dosimetric Implications of Calculating Lung Shunt Fraction for Hepatic Yttrium-90 Radioembolization Using SPECT/CT Versus Planar Scintigraphy. AJR Am J Roentgenol 2021; 218:728-737. [PMID: 34704460 DOI: 10.2214/ajr.21.26663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background: Accurate assessment of hepatopulmonary shunting, typically performed by planar scintigraphy, is critical in planning yttrium-90 radioembolization. High lung shunt fractions (LSFs) may alter treatment. Objective: To compare LSFs calculated from planar scintigraphy versus SPECT/CT in patients with high planar LSFs (>15%) and to describe potential clinical and dosimetric implications of SPECT/CT LSF calculations. Methods: This retrospective study included 36 patients (29 male, 7 female; mean age 62.4±9.8 years) who underwent technetium-99m labeled macroaggregated albumin planar scintigraphy for planning hepatic radioembolization, with planar LSF >15% and concurrent SPECT/CT. Clinically reported planar LSFs were recorded. SPECT/CT LSFs were retrospectively calculated using automatically generated volumetric ROIs around the lungs and liver with subsequent manual adjustments. Total lung and perfused liver doses were calculated using a medical internal radiation dose model. Values derived from planar and SPECT/CT data were compared with Mann-Whitney U tests. Multivariable regression analysis was performed of factors associated with LSF discrepancy between techniques. Results: Mean planar LSF was 25.1%±11.6%; mean SPECT/CT LSF was 16.0%±9.3% (p<.001). Mean lung dose was 18.8±8.0 Gy for planar LSF versus 12.3±7.2 Gy for SPECT/CT LSF (p<.001). Mean perfused liver dose was 92.9±36.1 Gy using planar LSF versus 102.7±39.1 Gy using SPECT/CT LSF (p<.001). In multivariable analysis, larger discrepancy in LSF between planar scintigraphy and SPECT/CT was associated with body mass index ≥26 (p=.02), maximum tumor size <9 cm (p = .05), and left hepatic intra-arterial injection (p=.02). Fourteen of 36 patients did not undergo upfront radioembolization due to planar LSF >20%, instead undergoing shunt-reducing embolization with subsequent radioembolization (n=7), transarterial chemoembolization (n=5), or no treatment (n=2). Five of these 14 patients had SPECT/CT LSF <20% and would have been eligible for upfront radioembolization based on SPECT/CT LSF. Seven of 29 patients treated with radioembolization underwent prescribed dose reductions based on planar LSF; six of these patients would have qualified for standard radioembolization without dose reduction using SPECT/CT LSF. Conclusion: Planar scintigraphy yields greater LSFs compared to SPECT/CT, possibly leading to unnecessary shunt-reducing procedures and prescribed dose reductions. Clinical Impact: SPECT/CT should be considered for clinical LSF calculations before radioembolization in patients with high LSFs.
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22
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Georgiou MF, Kuker RA, Studenski MT, Ahlman PP, Witte M, Portelance L. Lung shunt fraction calculation using 99mTc-MAA SPECT/CT imaging for 90Y microsphere selective internal radiation therapy of liver tumors. EJNMMI Res 2021; 11:96. [PMID: 34585259 PMCID: PMC8479035 DOI: 10.1186/s13550-021-00837-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 09/11/2021] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND 99mTc-macroaggregated albumin (99mTc-MAA) scintigraphy is utilized in treatment planning for Yttrium-90 (90Y) Selective Internal Radiation Therapy (SIRT) of liver tumors to evaluate hepatopulmonary shunting by calculating the lung shunt fraction (LSF). The purpose of this study was to evaluate if LSF calculation using SPECT/CT instead of planar gamma camera imaging is more accurate and if this can potentially lead to more effective treatment planning of hepatic lesions while avoiding excessive pulmonary irradiation. RESULTS LSF calculation was obtained using two different methodologies in 85 cases from consecutive patients intended to receive 90Y SIRT. The first method was based on planar gamma camera imaging in the anterior and posterior views with geometric mean calculation of the LSF from regions of interest of the liver and lungs. The second method was based on segmentation of the liver and lungs from SPECT/CT images of the thorax and abdomen. The differences in planar imaging versus SPECT/CT derived LSF values along with the estimated absorbed lung mean dose (LMD) were evaluated. The LSF values were higher in planar imaging versus SPECT/CT in 81/85 cases, with a mean value of 8.5% vs. 4.6% respectively; the difference was statistically significant using a paired t-test (alpha = 0.05). In those patients who received SIRT, the estimated absorbed LMD calculated with planar imaging was significantly higher than with SPECT/CT (t-test, P < 0.005). Repeated phantom experiments using an anthropomorphic torso phantom with variable 99mTc activity concentrations for the liver and lungs were performed with the standard patient protocol, demonstrated improved accuracy of the LSF calculation based on SPECT/CT than planar imaging (mean overestimated value of 6% vs. 26%). CONCLUSIONS This study demonstrates that LSF calculation using planar imaging can be significantly overestimated while calculation using SPECT/CT imaging and appropriate segmentation tools can be more accurate. Minimizing the errors in obtaining the LSF can lead to more effective 90Y SIRT treatment planning for hepatic tumors while ensuring the lung dose will not exceed the standard acceptable safety thresholds.
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Affiliation(s)
- Mike F Georgiou
- Department of Radiology, Miller School of Medicine, University of Miami, 1611 NW 12th Avenue, JMH C-248, Miami, FL, 33136, USA.
| | - Russ A Kuker
- Department of Radiology, Miller School of Medicine, University of Miami, 1611 NW 12th Avenue, JMH C-248, Miami, FL, 33136, USA
| | - Matthew T Studenski
- Department of Radiation Oncology, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Preeti P Ahlman
- Department of Radiology, Miller School of Medicine, University of Miami, 1611 NW 12th Avenue, JMH C-248, Miami, FL, 33136, USA
| | - Megan Witte
- Department of Biomedical Engineering, University of Miami, Miami, FL, USA
| | - Lorraine Portelance
- Department of Radiation Oncology, Miller School of Medicine, University of Miami, Miami, FL, USA
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23
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Accurate non-tumoral 99mTc-MAA absorbed dose prediction to plan optimized activities in liver radioembolization using resin microspheres. Phys Med 2021; 89:250-257. [PMID: 34438353 DOI: 10.1016/j.ejmp.2021.07.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 07/23/2021] [Accepted: 07/28/2021] [Indexed: 12/19/2022] Open
Abstract
AIM The manufacturers' recommended methods to calculate delivered activities in liver radioembolization are simplistic and only slightly personalized. Activity planning could also be based on a 99mTc-macroaggregated albumin SPECT/CT (MAA) using the partition model but its accuracy is controversial. This study evaluates the dose parameters in the normal liver and in the tumor compartments using MAA SPECT/CT (pre-therapeutic imaging) and 90Y TOF-PET/CT (post-therapy imaging). Finally, we propose a prescription of the activity as a function of the normal liver MAA distribution. METHOD 66 procedures of RE (with resin microspheres) corresponding to 171 lesions were analyzed. Tumor to normal targeted liver uptake (T/NTL), tumor absorbed dose (TD) and whole normal liver absorbed (WNLD) were assessed with MAA and 90Y imaging. Secondly, activities were recalculated using the MAA distribution in the normal liver compartment to reach the maximal tolerable liver dose. These Activities were compared to activities defined with the BSA method. RESULTS Compared to 90Y imaging, our study demonstrated an accurate estimation of the WNLD using MAA imaging (Pearson's R = 0.97, p < 0.001). On the contrary, significant variations were found for TD (R = 0.65, p < 0.001). The MAA T/NTL ratio has a 85% positive predictive value in identifying patients who will get a 90Y T/NTL ratio above 1.5. Moreover, activities calculated using the MAA distribution in the normal liver compartment were significantly higher to activities defined with the BSA method. CONCLUSION Whole normal liver absorbed doses are accurately predicted with MAA imaging and could be used to optimize the activity planning.
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24
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Lu Z, Chen G, Lin KH, Wu TH, Mok GSP. Evaluation of different CT maps for attenuation correction and segmentation in static 99m Tc-MAA SPECT/CT for 90 Y radioembolization treatment planning: A simulation study. Med Phys 2021; 48:3842-3851. [PMID: 34013551 DOI: 10.1002/mp.14991] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 05/04/2021] [Accepted: 05/08/2021] [Indexed: 11/08/2022] Open
Abstract
PURPOSE Conventional 99m Tc-macroaggregated albumin (99m Tc-MAA) planar scintigraphy overestimates lung shunt fraction (LSF) compared to SPECT/CT. However, the respiratory motion artifact due to the temporal mismatch between static SPECT and helical CT (HCT) may compromise the SPECT quantitation accuracy by incorrect attenuation correction (AC) and volume-of-interest (VOI) segmentation. This study aims to evaluate AC and VOI segmentation effects systematically and to propose a CT map for LSF and tumor-to-normal liver ratio (TNR) estimation in static 99m Tc-MAA SPECT/CT. METHODS The 4D XCAT phantom was used to simulate a phantom population of 120 phantoms, modeling 10 different anatomical variations, nine TNRs (2-13.2), nine tumor sizes (2-6.7 cm diameter), eight tumor locations, three axial motion amplitudes of 1, 1.5, and 2 (cm), and four LSFs of 5%, 10%, 15%, and 20%. An analytical projector for low-energy high-resolution parallel-hole collimator was used to simulate 60 noisy projections over 360°, modeling attenuation and geometric collimator-detector response (GCDR). AC and VOI mismatch effects were investigated independently and together, using cine average CT (CACT), HCT at end-inspiration (HCT-IN), mid-respiration (HCT-MID), and end-expiration (HCT-EX) respectively as attenuation and segmentation maps. SPECT images without motion, AC, and VOI errors were also generated as reference. LSF and TNR errors were measured as compared to the ground truth. RESULTS HCT-MID has slightly better performance for AC effect compared with other CT maps in LSF and TNR estimation, while HCT-EX and HCT-MID perform better for VOI effect. For a respiratory motion amplitude of 1.5 cm and a LSF of 5%, the LSF errors are 19.56 ± 4.58%, -6.79 ± 1.74%, 77.29 ± 14.74%, and 111.25 ± 18.29% corresponding to HCT-MID, HCT-EX, HCT-IN, and CACT in static SPECT. The TNR errors are -12.38 ± 6.42%, -20.55 ± 11.25%, -20.89 ± 9.98%, and -22.89 ± 14.38% respectively. HCT-MID has the best performance for LSF estimation for LSF > 10% and TNR estimation, followed by HCT-EX, HCT-IN, and CACT. CONCLUSIONS The HCT-MID is recommended for AC and segmentation to alleviate respiratory artifacts and improve quantitation accuracy in 90 Y radioembolization treatment planning. HCT-EX would also be a recommended choice if HCT-MID is not available.
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Affiliation(s)
- Zhonglin Lu
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Avenida da Universidade, Taipa, Macau SAR, China
| | - Gefei Chen
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Avenida da Universidade, Taipa, Macau SAR, China
| | - Kuan-Heng Lin
- Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Industrial PhD Program of Biomedical Science and Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Tung-Hsin Wu
- Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Greta S P Mok
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Avenida da Universidade, Taipa, Macau SAR, China.,Center for Cognitive and Brain Sciences, Institute of Collaborative Innovation, University of Macau, Avenida da Universidade, Taipa, Macau SAR, China
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25
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Esposito TVF, Stütz H, Rodríguez-Rodríguez C, Bergamo M, Charles L, Geczy R, Blackadar C, Kutter JP, Saatchi K, Häfeli UO. Preparation of Heat-Denatured Macroaggregated Albumin for Biomedical Applications Using a Microfluidics Platform. ACS Biomater Sci Eng 2021; 7:2823-2834. [PMID: 33826291 DOI: 10.1021/acsbiomaterials.1c00284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Albumin is widely used in pharmaceutical applications to alter the pharmacokinetic profile, improve efficacy, or decrease the toxicity of active compounds. Various drug delivery systems using albumin have been reported, including microparticles. Macroaggregated albumin (MAA) is one of the more common forms of albumin microparticles, which is predominately used for lung perfusion imaging when labeled with radionuclide technetium-99m (99mTc). These microparticles are formed by heat-denaturing albumin in a bulk solution, making it very challenging to control the size and dispersity of the preparations (coefficient of variation, CV, ∼50%). In this work, we developed an integrated microfluidics platform to create more tunable and precise MAA particles, the so-called microfluidic-MAA (M2A2). The microfluidic chips, prepared using off-stoichiometry thiol-ene chemistry, consist of a flow-focusing region followed by an extended and water-heated curing channel (85 °C). M2A2 particles with diameters between 70 and 300 μm with CVs between 10 and 20% were reliably prepared by adjusting the flow rates of the dispersed and continuous phases. To demonstrate the pharmaceutical utility of M2A2, particles were labeled with indium-111 (111In) and their distribution was assessed in healthy mice using nuclear imaging. 111In-M2A2 behaved similarly to 99mTc-MAA, with lung uptake predominately observed early on followed by clearance over time by the reticuloendothelial and renal systems. Our microfluidic chip represents an elegant and controllable method to prepare albumin microparticles for biomedical applications.
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Affiliation(s)
- Tullio V F Esposito
- Faculty of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Helene Stütz
- Faculty of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Department of Life Science, IMC University of Applied Sciences, Piaristengasse 1, 3500 Krems, Austria
| | - Cristina Rodríguez-Rodríguez
- Faculty of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Department of Physics and Astronomy, Faculty of Science, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia V6T 1Z3, Canada
| | - Marta Bergamo
- Faculty of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Lovelyn Charles
- Faculty of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Reka Geczy
- Faculty of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Colin Blackadar
- Faculty of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Jörg P Kutter
- Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Katayoun Saatchi
- Faculty of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Urs O Häfeli
- Faculty of Pharmaceutical Sciences, University of British Columbia, 2405 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada.,Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
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Systematic review of lung shunt fraction quantification comparing SPECT/CT and planar scintigraphy for yttrium 90 radioembolization planning. Clin Transl Imaging 2021. [DOI: 10.1007/s40336-021-00417-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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27
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Stella M, Braat AJAT, Lam MGEH, de Jong HWAM, van Rooij R. Gamma camera characterization at high holmium-166 activity in liver radioembolization. EJNMMI Phys 2021; 8:22. [PMID: 33651253 PMCID: PMC7925770 DOI: 10.1186/s40658-021-00372-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 02/23/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND High activities of holmium-166 (166Ho)-labeled microspheres are used for therapeutic radioembolization, ideally directly followed by SPECT imaging for dosimetry purposes. The resulting high-count rate potentially impacts dead time, affecting the image quality and dosimetric accuracy. This study assesses gamma camera performance and SPECT image quality at high 166Ho activities of several GBq. To this purpose, the liver compartment, including two tumors, of an anthropomorphic phantom was filled with 166Ho-chloride, with a tumor to non-tumorous liver activity concentration ratio of 10:1. Multiple SPECT/CT scans were acquired over a range of activities up to 2.7 GBq. Images were reconstructed using a commercially available protocol incorporating attenuation and scatter correction. Dead time effects were assessed from the observed count rate in the photopeak (81 keV, 15% width) and upper scatter (118 keV, 12% width) window. Post reconstruction, each image was scaled with an individual conversion factor to match the known total activity in the phantom at scanning time. The resulting activity concentration was measured in the tumors and non-tumorous liver. The image quality as a function of activity was assessed by a visual check of the absence of artifacts by a nuclear medicine physician. The apparent lung shunt fraction (nonzero due to scatter) was estimated on planar and SPECT images. RESULTS A 20% count loss due to dead time was observed around 0.7 GBq in the photopeak window. Independent of the count losses, the measured activity concentration was up to 100% of the real value for non-tumorous liver, when reconstructions were normalized to the known activity at scanning time. However, for tumor spheres, activity concentration recovery was ~80% at the lowest activity, decreasing with increasing activity in the phantom. Measured lung shunt fractions were relatively constant over the considered activity range. CONCLUSIONS At high 166Ho count rate, all images, visually assessed, presented no artifacts, even at considerable dead time losses. A quantitative evaluation revealed the possibility of reliable dosimetry within the healthy liver, as long as a post-reconstruction scaling to scanning activity is applied. Reliable tumor dosimetry, instead, remained hampered by the dead time.
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Affiliation(s)
- Martina Stella
- Department of Radiology and Nuclear Medicine, UMC Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
| | - Arthur J A T Braat
- Department of Radiology and Nuclear Medicine, UMC Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Marnix G E H Lam
- Department of Radiology and Nuclear Medicine, UMC Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Hugo W A M de Jong
- Department of Radiology and Nuclear Medicine, UMC Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Rob van Rooij
- Department of Radiology and Nuclear Medicine, UMC Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
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Kappadath SC, Lopez BP, Salem R, Lam MG. Lung shunt and lung dose calculation methods for radioembolization treatment planning. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF RADIOPHARMACEUTICAL CHEMISTRY AND BIOLOGY 2021; 65:32-42. [PMID: 33393753 DOI: 10.23736/s1824-4785.20.03287-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Radioembolization, also known as selective internal radiation therapy (SIRT), is firmly established in the management of patients with unresectable liver cancers. Advances in normal and tumor liver dosimetry and new knowledge about tumor dose response relationships have helped promote the safe use of higher prescribed doses, consequently transitioning radioembolization from palliative to curative therapy. The lungs are considered a critical organ of risk for radioembolization treatment planning. Unfortunately, lung dosimetry has not achieved similar advances in dose calculation methodology as liver dosimetry. Current estimations of lung dose are dependent on a number of parameters associated with data acquisition and processing algorithms, leading to poor accuracy and precision. Therefore, the efficacy of curative radioembolization may be compromised in patients for whom the lung dose derived using currently available methods unnecessarily limits the desired administered activity to the liver. We present a systematic review of the various methods of determining the lung shunt fraction (LSF) and lung mean dose (LD). This review encompasses pretherapy estimations and post-therapy assessments of the LSF and LD using both 2D planar and 3D SPECT/CT based calculations. The advantages and limitations of each of these methods are deliberated with a focus on accuracy and practical considerations. We conclude the review by presenting a lexicon to precisely describe the methodology used for the estimation of LSF and LD; specifically, category, agent, modality, contour and algorithm, in order to aid in their interpretation and standardization in routine clinical practice.
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Affiliation(s)
- S Cheenu Kappadath
- Department of Imaging Physics, UT MD Anderson Cancer Center, Houston, TX, USA -
| | - Benjamin P Lopez
- Department of Imaging Physics, UT MD Anderson Cancer Center, Houston, TX, USA
| | - Riad Salem
- Department of Radiology, Northwestern Memorial Hospital, Chicago, IL, USA
| | - Marnix G Lam
- Department of Radiology and Nuclear Medicine, University Medical Center, Utrecht, The Netherlands
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Bulman JC, Zurkiya O, Wu V, Wehrenberg-Klee E, Palmer E, Chow D, Brook A, Ganguli S. Repeat Evaluation of Lung Shunt Fraction is Unnecessary: A Retrospective Observational Study of Successive Lung Shunt Fractions from Variable Arterial Distributions in Patients Undergoing Radioembolization of Primary and Secondary Liver Tumors. J Vasc Interv Radiol 2020; 32:412-418. [PMID: 33341340 DOI: 10.1016/j.jvir.2020.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/15/2020] [Accepted: 11/04/2020] [Indexed: 10/22/2022] Open
Abstract
PURPOSE To evaluate whether the recalculation of lung shunt fraction (LSF) is necessary prior to next-stage or same lobe repeat radioembolization. MATERIALS AND METHODS Retrospective chart review was performed for patients who underwent radioembolization between February 2008 and December 2018. Eighty of 312 patients had repeat mapping angiograms and LSF calculations. A total of 160 LSF calculations were made using planar imaging (155, [97%]) and single-photon emission computed tomography (5 [3%]) technetium-99m macroaggregated albumin hepatic arterial injection imaging. The mean patient age was 61.8 years ± 12.7; 69 (86%) patients had metastatic disease and 11 (14%) had hepatocellular carcinoma. RESULTS Patients had a median LSF of 5% (interquartile range [IQR] 3%-9%) with a median absolute difference of 1.25 (IQR 0.65-3.4) and a median of 76 days (IQR 42.5-120 days) between repeat LSF calculations. There was a median change in LSF of 0.2% between mapping studies (P = .11). There was no statistical significance between the repeat LSFs regardless of the arterial distribution (P = .79) or between tumor types (P = .75). No patients exceeded lung dose limits using actual or predicted prescribed dose amounts. The actual median lung dose was 2.6 Gy (IQR 1.8-4.4 Gy, maximum = 20.5) for the first radioembolization and 2.0 Gy (IQR 1.3-3.7 Gy, maximum = 10.1) for the second radioembolization. CONCLUSIONS No significant difference in LSF was identified between different time points and arterial distributions within the same patient undergoing repeat radioembolization. In patients who receive well under 30-Gy lung dose for the initial treatment and a 50-Gy cumulative lung dose, repeat radioembolization treatments in the same patient may not require a repeat LSF calculation.
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Affiliation(s)
- Julie C Bulman
- Department of Radiology, Beth Israel Deaconess Medical Center, 1 Deaconess Road, Boston, MA 02215.
| | - Omar Zurkiya
- Massachusetts General Hospital, 55 Fruit Street GRB 298, Boston, MA 02114
| | - Vincent Wu
- Massachusetts General Hospital, 55 Fruit Street GRB 298, Boston, MA 02114
| | | | - Edwin Palmer
- Massachusetts General Hospital, 55 Fruit Street GRB 298, Boston, MA 02114
| | - David Chow
- Massachusetts General Hospital, 55 Fruit Street GRB 298, Boston, MA 02114
| | - Alexander Brook
- Department of Radiology, Beth Israel Deaconess Medical Center, 1 Deaconess Road, Boston, MA 02215
| | - Suvranu Ganguli
- Boston Medical Center, One Boston Medical Center Place, Boston, MA 02118
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Villalobos A, Soliman MM, Majdalany BS, Schuster DM, Galt J, Bercu ZL, Kokabi N. Yttrium-90 Radioembolization Dosimetry: What Trainees Need to Know. Semin Intervent Radiol 2020; 37:543-554. [PMID: 33328711 PMCID: PMC7732571 DOI: 10.1055/s-0040-1720954] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Alexander Villalobos
- Division of Interventional Radiology and Image Guided Medicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia
| | - Mohamed M. Soliman
- Weill Cornell Medicine – Qatar School of Medicine, Education City, Al Luqta St, Ar-Rayyan, Qatar
| | - Bill S. Majdalany
- Division of Interventional Radiology and Image Guided Medicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia
| | - David M. Schuster
- Division of Nuclear and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia
| | - James Galt
- Division of Nuclear and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia
| | - Zachary L. Bercu
- Division of Interventional Radiology and Image Guided Medicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia
| | - Nima Kokabi
- Division of Interventional Radiology and Image Guided Medicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia
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Auditore L, Amato E, Boughdad S, Meyer M, Testart N, Cicone F, Beigelman-Aubry C, Prior JO, Schaefer N, Gnesin S. Monte Carlo 90Y PET/CT dosimetry of unexpected focal radiation-induced lung damage after hepatic radioembolisation. Phys Med Biol 2020; 65:235014. [PMID: 33245055 DOI: 10.1088/1361-6560/abbc80] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Transarterial radioembolization (TARE) with 90Y-loaded microspheres is an established therapeutic option for inoperable hepatic tumors. Increasing knowledge regarding TARE hepatic dose-response and dose-toxicity correlation is available but few studies have investigated dose-toxicity correlation in extra-hepatic tissues. We investigated absorbed dose levels for the appearance of focal lung damage in a case of off-target deposition of 90Y microspheres and compared them with the corresponding thresholds recommended to avoiding radiation induced lung injury following TARE. A 64-year-old male patient received 1.6 GBq of 90Y-labelled glass microspheres for an inoperable left lobe hepatocellular carcinoma. A focal off-target accumulation of radiolabeled microspheres was detected in the left lung upper lobe at the post-treatment 90Y-PET/CT, corresponding to a radiation-induced inflammatory lung lesion at the 3-months 18F-FDG PET/CT follow-up. 90Y-PET/CT data were used as input for Monte-Carlo based absorbed dose estimations. Dose-volume-histograms were computed to characterize the heterogeneity of absorbed dose distribution. The dose level associated with the appearance of lung tissue damage was estimated as the median absorbed dose measured at the edge of the inflammatory nodule. To account for respiratory movements and possible inaccuracy of image co-registration, three different methods were evaluated to define the irradiated off-target volume. Monte Carlo-derived absorbed dose distribution showed a highly heterogeneous absorbed dose pattern at the site of incidental microsphere deposition (volume = 2.13 ml) with a maximum dose of 630 Gy. Absorbed dose levels ranging from 119 Gy to 133 Gy, were estimated at the edge of the inflammatory nodule, depending on the procedure used to define the target volume. This report describes an original Monte Carlo based patient-specific dosimetry methodology for the study of the radiation-induced damage in a focal lung lesion after TARE. In our patient, radiation-induced focal lung damage occurred at significantly higher absorbed doses than those considered for single administration or cumulative lung dose delivered during TARE.
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Affiliation(s)
- Lucrezia Auditore
- Section of Radiological Sciences, Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Italy
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Elsayed M, Cheng B, Xing M, Sethi I, Brandon D, Schuster DM, Bercu Z, Galt J, Barron B, Kokabi N. Comparison of Tc-99m MAA Planar Versus SPECT/CT Imaging for Lung Shunt Fraction Evaluation Prior to Y-90 Radioembolization: Are We Overestimating Lung Shunt Fraction? Cardiovasc Intervent Radiol 2020; 44:254-260. [PMID: 33000319 DOI: 10.1007/s00270-020-02638-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 08/27/2020] [Indexed: 10/23/2022]
Abstract
PURPOSE To compare lung shunt fraction (LSF) prior to Y-90 radioembolization calculated using planar imaging versus SPECT/CT in patients with hepatocellular carcinoma (HCC). METHODS A single institution retrospective analysis of technetium-99m macroaggregated albumin (Tc-99m MAA) LSF studies for 293 consecutive patients with HCC between 2013 and 2018 was performed. LSF using planar imaging (PLSF) was compared to retrospectively calculated LSF using SPECT/CT (SLSF) via semiautomated segmentation using MIM v.6.9. Sub-analyses of patients were performed based on PLSF range, tumor size, BCLC stage, and Child-Pugh (C-P) score. Mean LSF absolute discrepancy between sub-groups was analyzed. Comparisons were performed using paired t tests and linear regression analysis. RESULTS Mean PLSF, 8.27%, was greater than mean SLSF, 3.27% (p < 0.001). When categorizing patients by PLSF ranges of < 10%, 10-19.9%, and ≥ 20%, PLSF remained greater than SLSF in all subgroups (p's < 0.001). Patients with PLSF ≥ 20% had a greater absolute discrepancy with SLSF (13.31%) compared to patients with PLSF < 20% (4.74%; p < 0.0001). LSF absolute discrepancy was greater for patients with a maximum liver tumor size ≥ 5.0 cm (5.59%) compared to a liver tumor size < 5.0 cm (4.40%; p = 0.0076). For all BCLC grades and C-P scores, PLSF was greater than SLSF. A greater LSF discrepancy existed for patients with a worse C-P score (C-P A: 4.78%, C-P B/C: 6.12%; p = 0.0081), but not BCLC stage (0/A/B: 4.87%, C: 4.56%; p = 0.5993). CONCLUSION In patients with HCC, SLSF is significantly lower compared to PLSF, with a greater discrepancy among patients with a PLSF ≥ 20%, tumor size ≥ 5 cm, and worse C-P score. LEVEL OF EVIDENCE Level 3, Retrospective Study.
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Affiliation(s)
- Mohammad Elsayed
- Division of Interventional Radiology and Image-Guided Medicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, 1364 Clifton Road NE, Suite BG03, Atlanta, GA, 30322, USA.
| | | | - Minzhi Xing
- Division of Interventional Radiology and Image-Guided Medicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, 1364 Clifton Road NE, Suite BG03, Atlanta, GA, 30322, USA
| | - Ila Sethi
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
| | - David Brandon
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
| | - David M Schuster
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
| | - Zachary Bercu
- Division of Interventional Radiology and Image-Guided Medicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, 1364 Clifton Road NE, Suite BG03, Atlanta, GA, 30322, USA
| | - James Galt
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
| | - Bruce Barron
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA, USA
| | - Nima Kokabi
- Division of Interventional Radiology and Image-Guided Medicine, Department of Radiology and Imaging Sciences, Emory University School of Medicine, 1364 Clifton Road NE, Suite BG03, Atlanta, GA, 30322, USA
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Abstract
Liver cancer is one of the top leading causes of mortality worldwide. Conventional imaging using contrast enhanced CT and MRI are currently the mainstay of oncologic imaging of the liver for the diagnosis and management of cancer. In the past two decades, especially since the advent of hybrid imaging in the form of PET/CT and SPECT/CT, molecular imaging has been increasingly utilized for oncologic imaging and the variety of radionuclide probes for imaging liver cancers have been expanding. Beyond the usual workhorse of FDG as an oncologic tracer, there is a growing body of evidence showing that radiolabeled choline tracers, C-11 acetate and other new novel tracers may have increasing roles to play for the imaging of liver tumors. On the therapy front, there have also been advances in recent times in terms of targeted therapies for both primary and secondary liver malignancies, particularly with transarterial radioembolization. The concept of theranostics can be applied to transarterial radioembolization by utilizing a pretreatment planning scan, such as Tc-99m macroaggregated albumin scintigraphy, coupled with post treatment imaging. Radiation dose planning by personalized dosimetric calculations to the liver tumors is also being advocated. This article explores the general trends in the field of nuclear medicine for the imaging and treatment of liver cancer above and beyond routine diagnosis and management.
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Affiliation(s)
- Aaron Kian-Ti Tong
- Singapore General Hospital, Department of Nuclear Medicine and Molecular Imaging; DUKE-NUS Graduate Medical School, Singapore.
| | - Wei Ying Tham
- Singapore General Hospital, Department of Nuclear Medicine and Molecular Imaging; DUKE-NUS Graduate Medical School, Singapore
| | - Chow Wei Too
- Singapore General Hospital, Department of Vascular and Interventional Radiology; DUKE-NUS Graduate Medical School, Singapore
| | - David Wai-Meng Tai
- National Cancer Centre Singapore, Division of Medical Oncology; DUKE-NUS Graduate Medical School, Singapore
| | - Pierce Kah-Hoe Chow
- Singapore General Hospital, Department of Hepato-Pancreato-Biliary (HPB) and Transplant Surgery; National Cancer Centre Singapore, Division of Surgical Oncology; DUKE-NUS Graduate Medical School, Singapore
| | - David Chee-Eng Ng
- Singapore General Hospital, Department of Nuclear Medicine and Molecular Imaging; DUKE-NUS Graduate Medical School, Singapore
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Stella M, Braat A, Lam M, de Jong H, van Rooij R. Quantitative 166Ho-microspheres SPECT derived from a dual-isotope acquisition with 99mTc-colloid is clinically feasible. EJNMMI Phys 2020; 7:48. [PMID: 32666401 PMCID: PMC7359973 DOI: 10.1186/s40658-020-00317-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 07/03/2020] [Indexed: 11/19/2022] Open
Abstract
Purpose Accurate dosimetry is essential in radioembolization. To this purpose, an automatic protocol for healthy liver dosimetry based on dual isotope (DI) SPECT imaging, combining holmium-166 (166Ho)-microspheres, and technetium-99 m (99mTc)-colloid was developed: 166Ho-microspheres used as scout and therapeutic particles, and 99mTc-colloid to identify the healthy liver. DI SPECT allows for an automatic and accurate estimation of absorbed doses, introducing true personalized dosimetry. However, photon crosstalk between isotopes can compromise image quality. This study investigates the effect of 99mTc downscatter on 166Ho dosimetry, by comparing 166Ho-SPECT reconstructions of patient scans acquired before (166Ho-only) and after additional administration of 99mTc-colloid (166Ho-DI). Methods The 166Ho-only and 166Ho-DI scans were performed in short succession by injecting 99mTc-colloid on the scanner table. To compensate for 99mTc downscatter, its influence was accounted for in the DI image reconstruction using energy window-based scatter correction methods. The qualitative assessment was performed by independent blinded comparison by two nuclear medicine physicians assessing 65 pairs of SPECT/CT. Inter-observer agreement was tested by Cohen’s kappa coefficient. For the quantitative analysis, two volumes of interest within the liver, VOITUMOR, and VOIHEALTHY were manually delineated on the 166Ho-only reconstruction and transferred to the co-registered 166Ho-DI reconstruction. Absorbed dose within the resulting VOIs, and in the lungs (VOILUNGS), was calculated based on the administered therapeutic activity. Results The qualitative assessment showed no distinct clinical preference for either 166Ho-only or 166Ho-DI SPECT (kappa = 0.093). Quantitative analysis indicated that the mean absorbed dose difference between 166Ho-DI and 166Ho-only was − 2.00 ± 2.84 Gy (median 27 Gy; p value < 0.00001), − 5.27 ± 8.99 Gy (median 116 Gy; p value = 0.00035), and 0.80 ± 1.08 Gy (median 3 Gy; p value < 0.00001) for VOIHEALTHY, VOITUMOR, and VOILUNGS, respectively. The corresponding Pearson’s correlation coefficient between 166Ho-only and 166Ho-DI for absorbed dose was 0.97, 0.99, and 0.82, respectively. Conclusion The DI protocol enables automatic dosimetry with undiminished image quality and accuracy. Clinical trials The clinical study mentioned is registered with Clinicaltrials.gov (NCT02067988) on 20 February 2014.
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Affiliation(s)
- M Stella
- Department of Radiology and Nuclear Medicine, University Medical Center, Utrecht, Heidelberglaan 100, 3584, CX, Utrecht, The Netherlands.
| | - Ajat Braat
- Department of Radiology and Nuclear Medicine, University Medical Center, Utrecht, Heidelberglaan 100, 3584, CX, Utrecht, The Netherlands
| | - Mgeh Lam
- Department of Radiology and Nuclear Medicine, University Medical Center, Utrecht, Heidelberglaan 100, 3584, CX, Utrecht, The Netherlands
| | - Hwam de Jong
- Department of Radiology and Nuclear Medicine, University Medical Center, Utrecht, Heidelberglaan 100, 3584, CX, Utrecht, The Netherlands
| | - R van Rooij
- Department of Radiology and Nuclear Medicine, University Medical Center, Utrecht, Heidelberglaan 100, 3584, CX, Utrecht, The Netherlands
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Mikell JK, Dewaraja YK, Owen D. Transarterial Radioembolization for Hepatocellular Carcinoma and Hepatic Metastases: Clinical Aspects and Dosimetry Models. Semin Radiat Oncol 2020; 30:68-76. [PMID: 31727302 DOI: 10.1016/j.semradonc.2019.08.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Transarterial radioembolization (TARE) with Yttrium-90 (90Y) microspheres is a liver-directed therapy for primary and metastatic disease. This manuscript provides a review of the clinical literature on TARE indications and efficacy with overviews of patient-selection and toxicity. Current dosimetry models used in practice are safe, relatively simple, and easy for clinicians to use. Planning currently relies on the imperfect surrogate, 99mTc macroaggregated albumin. Post-therapy quantitative imaging (90Y SPECT/CT or 90Y PET/CT) of microspheres can be used to calculate the macroscopic in vivo absorbed dose distribution. Similar to the evolution of other brachytherapy dose calculations, TARE is moving toward more patient-specific dosimetry that includes calculating and reporting nonuniform dose distributions throughout tumors and normal uninvolved liver.
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Affiliation(s)
- Justin K Mikell
- Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, MI.
| | - Yuni K Dewaraja
- Department of Radiology, University of Michigan Medical Center, Ann Arbor, MI
| | - Dawn Owen
- Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, MI
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Dual Modality Radiation With External Beam Radiation Therapy and Transarterial Radioembolization for Hepatocellular Carcinoma With Gross Vascular Invasion. Am J Clin Oncol 2019; 42:367-374. [PMID: 30724782 DOI: 10.1097/coc.0000000000000523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Patients with hepatocellular carcinoma (HCC) and gross vascular invasion (GVI) have poor outcomes with systemic therapy such as sorafenib. Both external beam radiation therapy (EBRT) and transarterial radioembolization (TARE) have been utilized for this patient population. We sought to compare outcomes using dual modality radiation (EBRT+TARE) versus EBRT alone in patients with HCC and GVI. MATERIALS AND METHODS Between 2011 and 2017, 45 patients with HCC and GVI were treated with EBRT±TARE at our institution. Progression-free survival (PFS) and overall survival (OS) were assessed and compared using Kaplan-Meier method and log-rank test. Univariable and multivariable Cox proportional hazards regression was used to assess the impact of the variables stage, etiology of cirrhosis, Child-Pugh (CP) score, and Karnofsky Performance Score (KPS) on PFS and OS. RESULTS Patient characteristics were well-balanced except for KPS (80 vs. 90) and CP score. Median OS for patients receiving EBRT+TARE was 263 days (95% confidence interval [CI]: 167, -) versus 193 days (95% CI: 51, 262) for EBRT alone (P=0.049). However, this did not hold up on MVA. When EBRT and TARE were delivered within 2 months as planned (n=12), median PFS was 218 days (95% CI: 44, -) for dual modality radiation versus 63 days (95% CI: 38, 137) for EBRT alone (P=0.048). When EBRT and TARE were delivered within 6 months, the difference in PFS was no longer seen (P=NS), because some patients received TARE as a salvage therapy. CONCLUSIONS Dual modality radiation with EBRT and TARE may be associated with improved OS in patients with HCC and GVI. Dual modality radiation may be associated with improved PFS in patients with HCC and GVI compared with EBRT alone when EBRT and TARE are delivered within 2 months of each other as part of a planned dual modality treatment strategy. However, since this is a retrospective study with inherent selection bias, these findings need further validation in a prospective clinical trial for patients with HCC and GVI.
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A guide to 90Y radioembolization and its dosimetry. Phys Med 2019; 68:132-145. [DOI: 10.1016/j.ejmp.2019.09.236] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 09/15/2019] [Accepted: 09/17/2019] [Indexed: 01/14/2023] Open
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Jadoul A, Bernard C, Lovinfosse P, Gérard L, Lilet H, Cornet O, Hustinx R. Comparative dosimetry between 99mTc-MAA SPECT/CT and 90Y PET/CT in primary and metastatic liver tumors. Eur J Nucl Med Mol Imaging 2019; 47:828-837. [PMID: 31388721 DOI: 10.1007/s00259-019-04465-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 07/26/2019] [Indexed: 12/22/2022]
Abstract
INTRODUCTION The aim of this study is to determine whether 99mTc-MAA SPECT/CT-based dosimetry could predict the actual absorbed dose in hepatocellular carcinoma (HCC) or liver metastases, treated by glass or resin microspheres. MATERIAL AND METHODS Fifty-seven patients who underwent selective internal radiation therapy (SIRT) were retrospectively included in the study, for a total of 59 treatments. Nineteen HCC were treated by resin microspheres (HCC-SIR), 20 HCC with glass microspheres (HCC-Thera), and 20 liver metastases with resin microspheres (Metastases-SIR). The mean absorbed doses in tumoral liver (Dm) and non-tumoral liver (DmNTL) were determined on the 99mTc-MAA SPECT/CT and the 90Y PET/CT, and compared with each other. RESULTS DmNTL was < 50 Gy in the 3 groups, with a strong correlation in all population, albeit slightly lower in Metastases-SIR than HCC-SIR and HCC-Thera (CCC 0.8, 0.94 and 0.96, respectively). In tumoral liver, Dm was higher in HCC than metastases (159 ± 117 Gy versus 63 ± 31 Gy). 99mTc-MAA SPECT/CT proved to be a better indicator of Dm in HCC compared with metastases, with similar 99mTc-MAA-90Y concordance in resin and glass microspheres (CCC HCC-SIR 0.82, CCC HCC-Thera 0.82, and CCC Metastases-SIR 0.52). CONCLUSION 99mTc-MAA SPECT/CT is a reasonably reliable tool for predicting the dose to the non-tumoral liver in both HCC and metastases, regardless of the type of microspheres. It is also fairly reliable for predicting the tumor dose in HCC, again regardless of the type of spheres, although individual variations are observed.
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Affiliation(s)
- Alexandre Jadoul
- Division of Nuclear Medicine and Oncological Imaging, University Hospital of Liege, B35 Domaine Universitaire du Sart-Tilman, 4000, Liege, Belgium.
| | - Claire Bernard
- Division of Nuclear Medicine and Oncological Imaging, University Hospital of Liege, B35 Domaine Universitaire du Sart-Tilman, 4000, Liege, Belgium
| | - Pierre Lovinfosse
- Division of Nuclear Medicine and Oncological Imaging, University Hospital of Liege, B35 Domaine Universitaire du Sart-Tilman, 4000, Liege, Belgium
| | - Laurent Gérard
- Division of Radiology, University Hospital of Liege, Liege, Belgium
| | - Henri Lilet
- Division of Nuclear Medicine and Oncological Imaging, University Hospital of Liege, B35 Domaine Universitaire du Sart-Tilman, 4000, Liege, Belgium
| | - Olivier Cornet
- Division of Radiology, University Hospital of Liege, Liege, Belgium
| | - Roland Hustinx
- Division of Nuclear Medicine and Oncological Imaging, University Hospital of Liege, B35 Domaine Universitaire du Sart-Tilman, 4000, Liege, Belgium
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Vermeulen K, Vandamme M, Bormans G, Cleeren F. Design and Challenges of Radiopharmaceuticals. Semin Nucl Med 2019; 49:339-356. [PMID: 31470930 DOI: 10.1053/j.semnuclmed.2019.07.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
This review describes general concepts with regard to radiopharmaceuticals for diagnostic or therapeutic applications that help to understand the specific challenges encountered during the design, (radio)synthesis, in vitro and in vivo evaluation and clinical translation of novel radiopharmaceuticals. The design of a radiopharmaceutical requires upfront decisions with regard to combining a suitable vector molecule with an appropriate radionuclide, considering the type and location of the molecular target, the desired application, and the time constraints imposed by the relatively short half-life of radionuclides. Well-designed in vitro and in vivo experiments allow nonclinical validation of radiotracers. Ultimately, in combination with a limited toxicology package, the radiotracer becomes a radiopharmaceutical for clinical evaluation, produced in compliance with regulatory requirements for medicines for intravenous (IV) injection.
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Affiliation(s)
- Koen Vermeulen
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, Leuven, Belgium
| | - Mathilde Vandamme
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, Leuven, Belgium
| | - Guy Bormans
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, Leuven, Belgium.
| | - Frederik Cleeren
- Laboratory for Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, Leuven, Belgium
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PET-CT post therapy dosimetry in radioembolization with resin 90Y microspheres: Comparison with pre-treatment SPECT-CT 99mTc-MAA results. Phys Med 2019; 64:16-23. [PMID: 31515015 DOI: 10.1016/j.ejmp.2019.05.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 05/02/2019] [Accepted: 05/27/2019] [Indexed: 01/05/2023] Open
Abstract
Resin microspheres radioembolization is an effective treatment for liver tumors when the surgical option is not feasible. Doses delivered to tumor and normal liver can be assess in the pre-therapy phase by means of a 99mTc-MAA SPECT-CT simulation and after the treatment with 90Y PET-CT acquisition. The optimal therapeutic 90Y activity is determined on 99mTc-MAA SPECT-CT dose results in order to avoid healthy parenchyma toxicity and to effectively irradiate the tumor. The assumption of identical radiopharmaceutical distribution between simulation and verification is still under debate and literature data showed controversial results. In this study 10 HCC patient's dosimetry performed on 99mTc SPECT-CT and 90Y PET-CT were compared. Patients were selected when a good agreement between the pre and post-therapy distribution was observed in order to investigate the intrinsic dosimetric variations between the two imaging modalities. Mean doses (MIRD and Voxel approaches) showed a good correlation (Pearson's coefficient r > 0.90) both for tumor and normal liver. Dose Volume Histogram curves were compared with a good agreement particularly for normal liver (D50). Goal doses were achieved for 90% of patients. Bland-Altman analysis indicates lower variations for healthy parenchyma than for tumor (1.96 SD equal to 9.1 Gy and 68 Gy respectively) confirming the robustness of the dose-toxicity approach. PET-CT dosimetry well correlates with SPECT-CT doses (under assumption of same catheter position and 90Y activity). Better agreement was showed for 7/10 and 8/10 patients for T and NL respectively, confirming dosimetry as effective tool to optimize and individualize the treatment.
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Calculation of lung mean dose and quantification of error for
90
Y‐microsphere radioembolization using
99m
Tc‐MAA SPECT/CT and diagnostic chest CT. Med Phys 2019; 46:3929-3940. [DOI: 10.1002/mp.13575] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 04/04/2019] [Accepted: 04/23/2019] [Indexed: 12/24/2022] Open
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