1
|
Yan S, Qiu R, Wu Z, Luo X, Hu Z, Li J. Individualized dose calculation for internal exposure on radionuclide intake: GPU acceleration approach. Phys Med Biol 2024; 69:175002. [PMID: 39084645 DOI: 10.1088/1361-6560/ad69fa] [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: 02/21/2024] [Accepted: 07/31/2024] [Indexed: 08/02/2024]
Abstract
Objective. The rapid and accurate assessment of internal exposure dose is a crucial safeguard for personnel health and safety. This study aims to investigate a precise and efficient GPU Monte Carlo simulation approach for internal exposure dose calculation. It directly calculates doses from common radioactive nuclides intake, like60Co for occupational exposure, allowing personalized assessments.Approach. This study developed a GPU-accelerated Monte Carlo program for internal exposure on radionuclide intake, successfully realizing photoelectronic coupled transport, nuclide simulation, and optimized acceleration. The generation of internal irradiation sources and sampling methods were achieved, along with the establishment of a personalized phantom construction process. Three irradiation scenarios were simulated to assess computational accuracy and efficiency, and to investigate the influence of posture variations on internal dose estimations.Main results. Using the International Commission on Radiological Protection (ICRP) voxel-type phantom, the internal dose of radionuclides in individual organs was calculated, exhibiting relative deviation of less than 3% in comparison to organ dose results interpolated by Specific Absorbed Fractions in ICRP Publication 133. Employing the Chinese reference phantom for calculating internal irradiation dose from the intake of various radionuclides, the use of GPU Monte Carlo program significantly shortened the simulation time compared to using CPU programs, by a factor of 150-500. Internal dose estimation utilizing a seated Chinese phantom revealed up to a 75% maximum difference in organ dose compared to the same phantom in a standing posture.Significance. This study presents a rapid GPU-based simulation method for internal irradiation doses, capable of directly simulating dose outcomes from nuclide intake and accommodating individualized phantoms for more realistic and expeditious calculations tailored to specific internal irradiation scenarios. It provides an effective and feasible tool for precisely calculating internal irradiation doses in real-world scenarios.
Collapse
Affiliation(s)
- Shuchang Yan
- Department of Engineering Physics, Tsinghua University, Beijing , People's Republic of China
- Key Laboratory of Particle & Radiation Imaging, Tsinghua University, Ministry of Education , Beijing, People's Republic of China
| | - Rui Qiu
- Department of Engineering Physics, Tsinghua University, Beijing , People's Republic of China
- Key Laboratory of Particle & Radiation Imaging, Tsinghua University, Ministry of Education , Beijing, People's Republic of China
| | - Zhen Wu
- Department of Engineering Physics, Tsinghua University, Beijing , People's Republic of China
- Key Laboratory of Particle & Radiation Imaging, Tsinghua University, Ministry of Education , Beijing, People's Republic of China
- Nuctech Company Limited , Beijing, People's Republic of China
| | - Xiyu Luo
- Department of Engineering Physics, Tsinghua University, Beijing , People's Republic of China
- Key Laboratory of Particle & Radiation Imaging, Tsinghua University, Ministry of Education , Beijing, People's Republic of China
| | - Ziyi Hu
- Department of Engineering Physics, Tsinghua University, Beijing , People's Republic of China
- Key Laboratory of Particle & Radiation Imaging, Tsinghua University, Ministry of Education , Beijing, People's Republic of China
| | - Junli Li
- Department of Engineering Physics, Tsinghua University, Beijing , People's Republic of China
- Key Laboratory of Particle & Radiation Imaging, Tsinghua University, Ministry of Education , Beijing, People's Republic of China
| |
Collapse
|
2
|
Sato T, Matsuya Y, Hamada N. Evaluation of relative biological effectiveness for diseases of the circulatory system based on microdosimetry. JOURNAL OF RADIATION RESEARCH 2024; 65:500-506. [PMID: 38924483 PMCID: PMC11262868 DOI: 10.1093/jrr/rrae051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 05/04/2024] [Indexed: 06/28/2024]
Abstract
In the next decade, the International Commission on Radiological Protection (ICRP) will issue the next set of general recommendations, for which evaluation of relative biological effectiveness (RBE) for various types of tissue reactions would be needed. ICRP has recently classified diseases of the circulatory system (DCS) as a tissue reaction, but has not recommended RBE for DCS. We therefore evaluated the mean and uncertainty of RBE for DCS by applying a microdosimetric kinetic model specialized for RBE estimation of tissue reactions. For this purpose, we analyzed several RBE data for DCS determined by past animal experiments and evaluated the radius of the subnuclear domain best fit to each experiment as a single free parameter included in the model. Our analysis suggested that RBE for DCS tends to be lower than that for skin reactions, and their difference was borderline significant due to large variances of the evaluated parameters. We also found that RBE for DCS following mono-energetic neutron irradiation of the human body is much lower than that for skin reactions, particularly at the thermal energy and around 1 MeV. This tendency is considered attributable not only to the intrinsic difference of neutron RBE between skin reactions and DCS but also to the difference in the contributions of secondary γ-rays to the total absorbed doses between their target organs. These findings will help determine RBE by ICRP for preventing tissue reactions.
Collapse
Affiliation(s)
- Tatsuhiko Sato
- Nuclear Science and Engineering Center, Japan Atomic Energy Agency (JAEA), Shirakata 2-4, Tokai, Ibaraki 319-1195, Japan
- Research Center for Nuclear Physics, Osaka University, Mihogaoka 10-1, Ibaraki, Osaka 567-0047, Japan
| | - Yusuke Matsuya
- Nuclear Science and Engineering Center, Japan Atomic Energy Agency (JAEA), Shirakata 2-4, Tokai, Ibaraki 319-1195, Japan
- Faculty of Health Sciences, Hokkaido University, Kita-12 Nishi-5, Kita-ku, Sapporo, Hokkaido 060-0812, Japan
| | - Nobuyuki Hamada
- Sustainable System Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), Iwado-kita 2-11-1, Komae, Tokyo 201-8511, Japan
| |
Collapse
|
3
|
Mack KN, Samuels ZV, Carter LM, Viray TD, Mandleywala K, Brooks CL, Hollingsworth MA, Radhakrishnan P, Lewis JS. Interrogating the Theranostic Capacity of a MUC16-Targeted Antibody for Ovarian Cancer. J Nucl Med 2024; 65:580-585. [PMID: 38485271 PMCID: PMC10995531 DOI: 10.2967/jnumed.123.266524] [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: 08/11/2023] [Revised: 01/29/2024] [Indexed: 04/04/2024] Open
Abstract
Aberrantly expressed glycans on mucins such as mucin-16 (MUC16) are implicated in the biology that promotes ovarian cancer (OC) malignancy. Here, we investigated the theranostic potential of a humanized antibody, huAR9.6, targeting fully glycosylated and hypoglycosylated MUC16 isoforms. Methods: In vitro and in vivo targeting of the diagnostic radiotracer [89Zr]Zr-DFO-huAR9.6 was investigated via binding experiments, immuno-PET imaging, and biodistribution studies on OC mouse models. Ovarian xenografts were used to determine the safety and efficacy of the therapeutic version, [177Lu]Lu-CHX-A″-DTPA-huAR9.6. Results: In vivo uptake of [89Zr]Zr-DFO-huAR9.6 supported in vitro-determined expression levels: high uptake in OVCAR3 and OVCAR4 tumors, low uptake in OVCAR5 tumors, and no uptake in OVCAR8 tumors. Accordingly, [177Lu]Lu-CHX-A″-DTPA-huAR9.6 displayed strong antitumor effects in the OVCAR3 model and improved overall survival in the OVCAR3 and OVCAR5 models in comparison to the saline control. Hematologic toxicity was transient in both models. Conclusion: PET imaging of OC xenografts showed that [89Zr]Zr-DFO-huAR9.6 delineated MUC16 expression levels, which correlated with in vitro results. Additionally, we showed that [177Lu]Lu-CHX-A″-DTPA-huAR9.6 displayed strong antitumor effects in highly MUC16-expressing tumors. These findings demonstrate great potential for 89Zr- and 177Lu-labeled huAR9.6 as theranostic tools for the diagnosis and treatment of OC.
Collapse
Affiliation(s)
- Kyeara N Mack
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Pharmacology, Weill Cornell Graduate School of Medical Sciences, Weill Cornell Medicine, New York, New York
| | - Zachary V Samuels
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Lukas M Carter
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Tara D Viray
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Komal Mandleywala
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Cory L Brooks
- Department of Chemistry and Biochemistry, California State University, Fresno, California
| | - Michael A Hollingsworth
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska; and
| | - Prakash Radhakrishnan
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska; and
| | - Jason S Lewis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York;
- Department of Pharmacology, Weill Cornell Graduate School of Medical Sciences, Weill Cornell Medicine, New York, New York
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| |
Collapse
|
4
|
Carter LM, Zanzonico PB. MIB Guides: Preclinical Radiopharmaceutical Dosimetry. Mol Imaging Biol 2024; 26:17-28. [PMID: 37964036 DOI: 10.1007/s11307-023-01868-9] [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: 08/03/2023] [Revised: 09/26/2023] [Accepted: 10/20/2023] [Indexed: 11/16/2023]
Abstract
Preclinical dosimetry is essential for guiding the design of animal radiopharmaceutical biodistribution, imaging, and therapy experiments, evaluating efficacy and/or toxicities in such experiments, ensuring compliance with ethical standards for animal research, and, perhaps most importantly, providing reasonable initial estimates of normal-organ doses in humans, required for clinical translation of new radiopharmaceuticals. This MIB Guide provides a basic protocol for obtaining preclinical dosimetry estimates with organ-level dosimetry software.
Collapse
Affiliation(s)
- Lukas M Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Pat B Zanzonico
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| |
Collapse
|
5
|
Bauer D, Carter LM, Atmane MI, De Gregorio R, Michel A, Kaminsky S, Monette S, Li M, Schultz MK, Lewis JS. 212Pb-Pretargeted Theranostics for Pancreatic Cancer. J Nucl Med 2024; 65:109-116. [PMID: 37945380 PMCID: PMC10755526 DOI: 10.2967/jnumed.123.266388] [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: 07/24/2023] [Revised: 09/28/2023] [Indexed: 11/12/2023] Open
Abstract
Although pancreatic ductal adenocarcinoma (PDAC) is associated with limited treatment options and poor patient outcomes, targeted α-particle therapy (TAT) represents a promising development in the field. TAT shows potential in treating metastatic cancers, including those that have become resistant to conventional treatments. Among the most auspicious radionuclides stands the in vivo α-generator 212Pb. Combined with the imaging-compatible radionuclide 203Pb, this theranostic match is a promising modality rapidly translating into the clinic. Methods: Using the pretargeting approach between a radiolabeled 1,2,4,5-tetrazine (Tz) tracer and a trans-cyclooctene (TCO) modified antibody, imaging and therapy with radiolead were performed on a PDAC tumor xenograft mouse model. For therapy, 3 cohorts received a single administration of 1.1, 2.2, or 3.7 MBq of the pretargeting agent, [212Pb]Pb-DO3A-PEG7-Tz, whereby administered activity levels were guided by dosimetric analysis. Results: The treated mice were holistically evaluated; minimal-to-mild renal tubular necrosis was observed. At the same time, median survival doubled for the highest-dose cohort (10.7 wk) compared with the control cohort (5.1 wk). Conclusion: This foundational study demonstrated the feasibility and safety of pretargeted TAT with 212Pb in PDAC while considering dose limitations and potential adverse effects.
Collapse
Affiliation(s)
- David Bauer
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Lukas M Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Mohamed I Atmane
- Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medicine, and Rockefeller University, New York, New York
| | - Roberto De Gregorio
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Alexa Michel
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Spencer Kaminsky
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sebastien Monette
- Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medicine, and Rockefeller University, New York, New York
| | - Mengshi Li
- Perspective Therapeutics, Inc., Coralville, Iowa; and
| | | | - Jason S Lewis
- Department of Radiology and Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York;
- Department of Radiology and Pharmacology Program, Weill Cornell Medical College, New York, New York
| |
Collapse
|
6
|
Carter LM, Zanzonico PB. MIB Guides: Preclinical radiopharmaceutical dosimetry. RESEARCH SQUARE 2023:rs.3.rs-3225362. [PMID: 37645915 PMCID: PMC10462246 DOI: 10.21203/rs.3.rs-3225362/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Preclinical dosimetry is essential for guiding the design of animal radiopharmaceutical biodistribution, imaging, and therapy experiments, evaluating efficacy and/or toxicities in such experiments, ensuring compliance with ethical standards for animal research, and providing reasonable initial estimates of normal-organ doses in humans, required for clinical translation of new radiopharmaceuticals. This MIB guide provides a basic protocol for obtaining preclinical dosimetry estimates with organ-level dosimetry software.
Collapse
Affiliation(s)
- Lukas M Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Pat B Zanzonico
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| |
Collapse
|
7
|
Carter LM, Ocampo Ramos JC, Olguin EA, Brown JL, Lafontaine D, Jokisch DW, Bolch WE, Kesner AL. MIRD Pamphlet No. 28, Part 2: Comparative Evaluation of MIRDcalc Dosimetry Software Across a Compendium of Diagnostic Radiopharmaceuticals. J Nucl Med 2023; 64:1295-1303. [PMID: 37268423 PMCID: PMC10394313 DOI: 10.2967/jnumed.122.264230] [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: 04/04/2022] [Revised: 03/21/2023] [Indexed: 06/04/2023] Open
Abstract
Radiopharmaceutical dosimetry is usually estimated via organ-level MIRD schema-style formalisms, which form the computational basis for commonly used clinical and research dosimetry software. Recently, MIRDcalc internal dosimetry software was developed to provide a freely available organ-level dosimetry solution that incorporates up-to-date models of human anatomy, addresses uncertainty in radiopharmaceutical biokinetics and patient organ masses, and offers a 1-screen user interface as well as quality assurance tools. The present work describes the validation of MIRDcalc and, secondarily, provides a compendium of radiopharmaceutical dose coefficients obtained with MIRDcalc. Biokinetic data for about 70 currently and historically used radiopharmaceuticals were obtained from the International Commission on Radiological Protection (ICRP) publication 128 radiopharmaceutical data compendium. Absorbed dose and effective dose coefficients were derived from the biokinetic datasets using MIRDcalc, IDAC-Dose, and OLINDA software. The dose coefficients obtained with MIRDcalc were systematically compared against the other software-derived dose coefficients and those originally presented in ICRP publication 128. Dose coefficients computed with MIRDcalc and IDAC-Dose showed excellent overall agreement. The dose coefficients derived from other software and the dose coefficients promulgated in ICRP publication 128 both were in reasonable agreement with the dose coefficients computed with MIRDcalc. Future work should expand the scope of the validation to include personalized dosimetry calculations.
Collapse
Affiliation(s)
- Lukas M Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York;
| | - Juan C Ocampo Ramos
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Edmond A Olguin
- Beth Israel Deaconess Medical Center, Department of Radiology, Harvard Medical School, Boston, Massachusetts
| | - Justin L Brown
- J. Crayton Pruitt Department of Biomedical Engineering, University of Florida, Gainesville, Florida
| | - Daniel Lafontaine
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Derek W Jokisch
- Department of Physics and Engineering, Francis Marion University, Florence, South Carolina; and
- Center for Radiation Protection Knowledge, Oak Ridge National Laboratory, Oak Ridge, Tennessee
| | - Wesley E Bolch
- J. Crayton Pruitt Department of Biomedical Engineering, University of Florida, Gainesville, Florida
| | - Adam L Kesner
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| |
Collapse
|
8
|
Carter LM, Bellamy MB, Choi C, Kim CH, Bolch WE, Jokisch D, Kesner AL. Influence of Body Posture on Internal Organ Dosimetry: Radiocesium Exposure Modeling Using Novel Posture-dependent Mesh Computational Phantoms. HEALTH PHYSICS 2023; 125:137-146. [PMID: 37195207 PMCID: PMC10313736 DOI: 10.1097/hp.0000000000001701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
ABSTRACT Current practice in reference internal dosimetry assumes a fixed upright standing posture is maintained throughout the dose-integration period. Recently, the mesh-type ICRP adult reference computational phantoms were transformed into different body postures (e.g., sitting, squatting) for use in occupational dose reconstruction applications. Here, for the first time, we apply this phantom series to the study of organ dose estimates following radionuclide intake. We consider the specific cases of 137 Cs and 134 Cs ingestion (accidental/occupational intake) with attention to variability in absorbed dose as a function of posture. The ICRP Publication 137 systemic biokinetic model for soluble cesium ingestion was used to compute organ-level time-integrated activity coefficients for reference adults, over a 50-y dose-integration period, for 134 Cs and 137 Cs (and its radioactive progeny 137m Ba). Mean posture time-allocations (h d -1 for standing, sitting, and lying) were taken from published survey data. In accord with modern dosimetry formalisms (e.g., MIRD, ICRP), a posture weighting factor was introduced that accounts for the fraction of time spent within each independent posture. Absorbed dose coefficients were computed using PHITS Monte Carlo simulations. ICRP 103 tissue weighting factors were applied along with the posture weighting factors to obtain committed effective dose per unit intake (Sv Bq -1 ). For 137 Cs ingestion, most organ absorbed dose coefficients were negligibly to marginally higher (< ~3%) for sitting or crouched (lying fetal/semi-fetal) postures maintained over the dose commitment period, relative to the upright standing posture. The committed effective dose coefficients were 1.3 × 10 -8 Sv Bq -1 137 Cs for standing, sitting, or crouched postures; thus, the posture-weighted committed effective dose was not significantly different than the committed effective dose for a maintained upright standing posture. For 134 Cs ingestion, most organ absorbed dose coefficients for the sitting and crouched postures were significantly larger than the standing posture, but the differences were still considered minor (< ~8% for most organs). The committed effective dose coefficients were 1.2 × 10 -8 Sv Bq -1 134 Cs for the standing posture and 1.3 × 10 -8 Sv Bq -1 134 Cs for the sitting or crouched posture. The posture-weighted committed effective dose was 1.3 × 10 -8 Sv Bq -1 134 Cs. Body posture has minor influence on organ-level absorbed dose coefficients and committed effective dose for ingestion of soluble 137 Cs or 134 Cs.
Collapse
Affiliation(s)
- LM Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - MB Bellamy
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - C Choi
- J. Crayton Pruitt Department of Nuclear Engineering, University of Florida, Gainesville, FL, USA
| | - CH Kim
- Department of Nuclear Engineering, Hanyang University, Seoul, Korea
| | - WE Bolch
- J. Crayton Pruitt Department of Nuclear Engineering, University of Florida, Gainesville, FL, USA
| | - D Jokisch
- Department of Physics, Francis Marion University, Florence, SC, USA
- Center for Radiation Protection Knowledge, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - AL Kesner
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| |
Collapse
|
9
|
Wang Y, Kong D, Gao H, Du C, Xue H, Liu K, Kong X, Zhang W, Yin Y, Wu T, Jiao Y, Sun L. Multiple Mesh-type Real Human Cell Models for Dosimetric Application Coupled with Monte Carlo Simulations. Radiat Res 2023; 200:176-187. [PMID: 37410090 DOI: 10.1667/rade-23-00020.1] [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: 02/06/2023] [Accepted: 06/14/2023] [Indexed: 07/07/2023]
Abstract
The mesh-type models are superior to voxel models in cellular dose assessment coupled with Monte Carlo codes. The aim of this study was to expand the micron-scale mesh-type models based on the fluorescence tomography of real human cells, and to investigate the feasibility of these models in the application of various irradiation scenarios and Monte Carlo codes. Six different human cell lines, including pulmonary epithelial BEAS-2B, embryonic kidney 293T, hepatocyte L-02, B-lymphoblastoid HMy2.CIR, Gastric mucosal GES-1, and intestine epithelial FHs74Int, were adopted for single mesh-type models reconstruction and optimization based on laser confocal tomography images. Mesh-type models were transformed into the format of polygon mesh and tetrahedral mesh for the GATE and PHITS Monte Carlo codes, respectively. The effect of model reduction was analyzed by dose assessment and geometry consideration. The cytoplasm and nucleus doses were obtained by designating monoenergetic electrons and protons as external irradiation, and S values with different "target-source" combinations were calculated by assigning radioisotopes as internal exposure. Four kinds of Monte Carlo codes were employed, i.e., GATE with "Livermore," "Standard" and "Standard and Geant4-DNA mixed" models for electrons and protons, as well as PHITS with "EGS" mode for electrons and radioisotopes. Multiple mesh-type real human cellular models can be applied to Monte Carlo codes directly without voxelization when combined with certain necessary surface reduction. Relative deviations between different cell types were observed among various irradiation scenarios. The relative deviation of nucleus S value reaches up to 85.65% between L-02 and GES-1 cells by 3H for the "nucleus-nucleus" combination, while that of 293T and FHs74Int nucleus dose for external beams at a 5.12 cm depth of water is 106.99%. Nucleus with smaller volume is far more affected by physical codes. There is a considerable deviation for dose within BEAS-2B at the nanoscale. The multiple mesh-type real cell models were more versatile than voxel models and mathematical models. The present study provided several models which can easily be extended to other cell types and irradiation scenarios for RBE estimations and biological effect predictions, including radiation biological experiments, radiotherapy and radiation protection.
Collapse
Affiliation(s)
- YiDi Wang
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| | - Dong Kong
- Department of Radiation Oncology, Affiliated Hospital of Jiangnan University, Wuxi, China
| | - Han Gao
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| | - ChuanSheng Du
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| | - HuiYuan Xue
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| | - Kun Liu
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| | - XiangHui Kong
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| | - WenYue Zhang
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| | - YuChen Yin
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| | - Tao Wu
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| | - Yang Jiao
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| | - Liang Sun
- State Key Laboratory of Radiation Medicine and Protection, Suzhou, China
- School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions, Suzhou, China
| |
Collapse
|
10
|
Carter LM, Krebs S, Marquis H, Ramos JCO, Olguin EA, Mason EO, Bolch WE, Zanzonico PB, Kesner AL. Dosimetric variability across a library of computational tumor phantoms. J Nucl Med 2023; 64:782-790. [PMID: 37074039 PMCID: PMC10152122 DOI: 10.2967/jnumed.122.264916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 11/29/2022] [Indexed: 12/13/2022] Open
Abstract
In radiopharmaceutical therapy, dosimetry-based treatment planning and response evaluation require accurate estimates of tumor-absorbed dose. Tumor dose estimates are routinely derived using simplistic spherical models, despite the well-established influence of tumor geometry on the dosimetry. Moreover, the degree of disease invasiveness correlates with departure from ideal geometry; malignant lesions often possess lobular, spiculated, or otherwise irregular margins in contrast to the commonly regular or smooth contours characteristic of benign lesions. To assess the effects of tumor shape, size, and margin contour on absorbed dose, an array of tumor geometries was modeled using computer-aided design software, and the models were used to calculate absorbed dose per unit of time-integrated activity (i.e., S values) for several clinically applied therapeutic radionuclides (90Y, 131I, 177Lu, 211At, 225Ac, 213Bi, and 223Ra). Methods: Three-dimensional tumor models of several different shape classifications were generated using Blender software. Ovoid shapes were generated using axial scaling. Lobulated, spiculated, and irregular contours were generated using noise-based mesh deformation. The meshes were rigidly scaled to different volumes, and S values were then computed using PARaDIM software. Radiomic features were extracted for each shape, and the impact on S values was examined. Finally, the systematic error present in dose calculations that model complex tumor shapes versus equivalent-mass spheres was estimated. Results: The dependence of tumor S values on shape was largest for extreme departures from spherical geometry and for long-range emissions (e.g., 90Y β-emissions). S values for spheres agreed reasonably well with lobulated, spiculated, or irregular contours if the surface perturbation was small. For marked deviations from spherical shape and small volumes, the systematic error of the equivalent-sphere approximation increased to 30%–75% depending on radionuclide. The errors were largest for shapes with many long spicules and for spherical shells with a thickness less than or comparable to the particle range in tissue. Conclusion: Variability in tumor S values as a function of tumor shape and margin contour was observed, suggesting use of contour-matched phantoms to improve the accuracy of tumor dosimetry in organ-level dosimetry paradigms. Implementing a library of tumor phantoms in organ-level dosimetry software may facilitate optimization strategies for personalized radionuclide therapies.
Collapse
Affiliation(s)
- Lukas M. Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Simone Krebs
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Harry Marquis
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Juan C. Ocampo Ramos
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Edmond A. Olguin
- Department of Radiology, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts
| | - Emilia O. Mason
- Department of Medicine, Sylvester Comprehensive Cancer Center, University of Miami, Miami, Florida; and
| | - Wesley E. Bolch
- J. Crayton Pruitt Department of Biomedical Engineering, University of Florida, Gainesville, Florida
| | - Pat B. Zanzonico
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Adam L. Kesner
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| |
Collapse
|
11
|
Rao Y, Samuels Z, Carter LM, Monette S, Panikar S, Pereira P, Lewis J. Statins enhance the efficacy of HER2-targeting radioligand therapy in drug-resistant gastric cancers. Proc Natl Acad Sci U S A 2023; 120:e2220413120. [PMID: 36972439 PMCID: PMC10083538 DOI: 10.1073/pnas.2220413120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 03/03/2023] [Indexed: 03/29/2023] Open
Abstract
Human epidermal growth factor receptor 2 (HER2) is overexpressed in various cancer types. HER2-targeting trastuzumab plus chemotherapy is used as first-line therapy for HER2-positive recurrent or primary metastatic gastric cancer, but intrinsic and acquired trastuzumab resistance inevitably develop over time. To overcome gastric cancer resistance to HER2-targeted therapies, we have conjugated trastuzumab with a beta-emitting therapeutic isotope, lutetium-177, to deliver radiation locally to gastric tumors with minimal toxicity. Because trastuzumab-based targeted radioligand therapy (RLT) requires only the extramembrane domain binding of membrane-bound HER2 receptors, HER2-targeting RLT can bypass any resistance mechanisms that occur downstream of HER2 binding. Leveraging our previous discoveries that statins, a class of cholesterol-lowering drugs, can enhance the cell surface-bound HER2 to achieve effective drug delivery in tumors, we proposed that the combination of statins and [177Lu]Lu-trastuzumab-based RLT can enhance the therapeutic efficacy of HER2-targeted RLT in drug-resistant gastric cancers. We demonstrate that lovastatin elevates cell surface HER2 levels and increases the tumor-absorbed radiation dose of [177Lu]Lu-DOTA-trastuzumab. Furthermore, lovastatin-modulated [177Lu]Lu-DOTA-trastuzumab RLT durably inhibits tumor growth and prolongs overall survival in mice bearing NCI-N87 gastric tumors and HER2-positive patient-derived xenografts (PDXs) of known clinical resistance to trastuzumab therapy. Statins also exhibit a radioprotective effect, reducing radiotoxicity in a mice cohort given the combination of statins and [177Lu]Lu-DOTA-trastuzumab. Since statins are commonly prescribed to patients, our results strongly support the feasibility of clinical studies that combine lovastatin with HER2-targeted RLT in HER2-postive patients and trastuzumab-resistant HER2-positive patients.
Collapse
Affiliation(s)
- Yi Rao
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY10065
| | - Zachary Samuels
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY10065
| | - Lukas M. Carter
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY10065
| | - Sebastien Monette
- Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, The Rockefeller University, Weill Cornell Medicine, New York, NY10065
| | - Sandeep Surendra Panikar
- Department of Radiology, Washington University School of Medicine in St. Louis, St. Louis, MO63110
| | - Patricia M. R. Pereira
- Department of Radiology, Washington University School of Medicine in St. Louis, St. Louis, MO63110
| | - Jason S. Lewis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY10065
- Department of Pharmacology, Weill Cornell Medicine, New York, NY10021
- Molecular Pharmacology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY10065
| |
Collapse
|
12
|
Katugampola S, Wang J, Rosen A, Howell RW. MIRD Pamphlet No. 27: MIRDcell V3, a Revised Software Tool for Multicellular Dosimetry and Bioeffect Modeling. J Nucl Med 2022; 63:1441-1449. [PMID: 35145016 PMCID: PMC9454469 DOI: 10.2967/jnumed.121.263253] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 01/26/2022] [Indexed: 01/26/2023] Open
Abstract
Radiopharmaceutical therapy is growing rapidly. However, yet to be addressed is the implementation of methods to plan treatments for circulating tumor cells, disseminated tumor cells, and micrometastases. Given the capacity of radiopharmaceuticals to specifically target and kill single cells and multicellular clusters, a quality not available in chemotherapy and external-beam radiation therapy, it is important to develop dosimetry and bioeffect modeling tools that can inform radiopharmaceutical design and predict their effect on microscopic disease. This pamphlet describes a new version of MIRDcell, a software tool that was initially released by the MIRD committee several years ago. Methods: Version 3 (V3) of MIRDcell uses a combination of analytic and Monte Carlo methods to conduct dosimetry and bioeffect modeling for radiolabeled cells within planar colonies and multicellular clusters. A worked example is provided to assist users to learn old and new features of MIRDcell and test its capacity to recapitulate published responses of tumor cell spheroids to radiopharmaceutical treatments. Prominent capabilities of the new version include radially dependent activity distributions, user-imported activity distributions, cold regions within the cluster, complex bioeffect modeling that accounts for radiation type and subcellular distribution, and a rich table of output data for subsequent analysis. Results: MIRDcell V3 effectively reproduces experimental responses of multicellular spheroids to uniform and nonuniform distributions of therapeutic radiopharmaceuticals. Conclusion: MIRDcell is a versatile software tool that can be used for educational purposes and design of radiopharmaceutical therapies.
Collapse
Affiliation(s)
- Sumudu Katugampola
- Division of Radiation Research, Department of Radiology, New Jersey Medical School, Rutgers University, Newark, New Jersey
| | - Jianchao Wang
- Division of Radiation Research, Department of Radiology, New Jersey Medical School, Rutgers University, Newark, New Jersey
| | - Alex Rosen
- Division of Radiation Research, Department of Radiology, New Jersey Medical School, Rutgers University, Newark, New Jersey
| | - Roger W Howell
- Division of Radiation Research, Department of Radiology, New Jersey Medical School, Rutgers University, Newark, New Jersey
| |
Collapse
|
13
|
Korsen JA, Gutierrez JA, Tully KM, Carter LM, Samuels ZV, Khitrov S, Poirier JT, Rudin CM, Chen Y, Morris MJ, Bodei L, Pillarsetty N, Lewis JS. Delta-like ligand 3-targeted radioimmunotherapy for neuroendocrine prostate cancer. Proc Natl Acad Sci U S A 2022; 119:e2203820119. [PMID: 35759660 PMCID: PMC9271187 DOI: 10.1073/pnas.2203820119] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/23/2022] [Indexed: 12/25/2022] Open
Abstract
Neuroendocrine prostate cancer (NEPC) is a lethal subtype of prostate cancer with limited meaningful treatment options. NEPC lesions uniquely express delta-like ligand 3 (DLL3) on their cell surface. Taking advantage of DLL3 overexpression, we developed and evaluated lutetium-177 (177Lu)-labeled DLL3-targeting antibody SC16 (177Lu-DTPA-SC16) as a treatment for NEPC. SC16 was functionalized with DTPA-CHX-A" chelator and radiolabeled with 177Lu to produce 177Lu-DTPA-SC16. Specificity and selectivity of 177Lu-DTPA-SC16 were evaluated in vitro and in vivo using NCI-H660 (NEPC, DLL3-positive) and DU145 (adenocarcinoma, DLL3-negative) cells and xenografts. Dose-dependent treatment efficacy and specificity of 177Lu-DTPA-SC16 radionuclide therapy were evaluated in H660 and DU145 xenograft-bearing mice. Safety of the agent was assessed by monitoring hematologic parameters. 177Lu-DTPA-SC16 showed high tumor uptake and specificity in H660 xenografts, with minimal uptake in DU145 xenografts. At all three tested doses of 177Lu-DTPA-SC16 (4.63, 9.25, and 27.75 MBq/mouse), complete responses were observed in H660-bearing mice; 9.25 and 27.75 MBq/mouse doses were curative. Even the lowest tested dose proved curative in five (63%) of eight mice, and recurring tumors could be successfully re-treated at the same dose to achieve complete responses. In DU145 xenografts, 177Lu-DTPA-SC16 therapy did not inhibit tumor growth. Platelets and hematocrit transiently dropped, reaching nadir at 2 to 3 wk. This was out of range only in the highest-dose cohort and quickly recovered to normal range by week 4. Weight loss was observed only in the highest-dose cohort. Therefore, our data demonstrate that 177Lu-DTPA-SC16 is a potent and safe radioimmunotherapeutic agent for testing in humans with NEPC.
Collapse
Affiliation(s)
- Joshua A. Korsen
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Department of Pharmacology, Weill Cornell Medicine, New York, NY 10021
| | - Julia A. Gutierrez
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Kathryn M. Tully
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Department of Pharmacology, Weill Cornell Medicine, New York, NY 10021
| | - Lukas M. Carter
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Zachary V. Samuels
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Samantha Khitrov
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - John T. Poirier
- Perlmutter Cancer Center, New York University Langone Health, New York, NY 10016
| | - Charles M. Rudin
- Department of Pharmacology, Weill Cornell Medicine, New York, NY 10021
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Yu Chen
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Michael J. Morris
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Department of Medicine, Weill Cornell Medicine, New York, NY 10021
| | - Lisa Bodei
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | | | - Jason S. Lewis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Department of Pharmacology, Weill Cornell Medicine, New York, NY 10021
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| |
Collapse
|
14
|
Bauer D, Visca H, Weerakkody A, Carter LM, Samuels Z, Kaminsky S, Andreev OA, Reshetnyak YK, Lewis JS. PET Imaging of Acidic Tumor Environment With 89Zr-labeled pHLIP Probes. Front Oncol 2022; 12:882541. [PMID: 35664740 PMCID: PMC9160799 DOI: 10.3389/fonc.2022.882541] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/19/2022] [Indexed: 11/13/2022] Open
Abstract
Acidosis of the tumor microenvironment is a hallmark of tumor progression and has emerged as an essential biomarker for cancer diagnosis, prognosis, and evaluation of treatment response. A tool for quantitatively visualizing the acidic tumor environment could significantly advance our understanding of the behavior of aggressive tumors, improving patient management and outcomes. 89Zr-labeled pH-low insertion peptides (pHLIP) are a class of radiopharmaceutical imaging probes for the in vivo analysis of acidic tumor microenvironments via positron emission tomography (PET). Their unique structure allows them to sense and target acidic cancer cells. In contrast to traditional molecular imaging agents, pHLIP's mechanism of action is pH-dependent and does not rely on the presence of tumor-specific molecular markers. In this study, one promising acidity-imaging PET probe ([89Zr]Zr-DFO-Cys-Var3) was identified as a candidate for clinical translation.
Collapse
Affiliation(s)
- David Bauer
- Department of Radiology and the Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Hannah Visca
- Department of Physics, University of Rhode Island, Kingston, RI, United States
| | - Anuradha Weerakkody
- Department of Physics, University of Rhode Island, Kingston, RI, United States
| | - Lukas M. Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Zachary Samuels
- Department of Radiology and the Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Spencer Kaminsky
- Department of Radiology and the Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
| | - Oleg A. Andreev
- Department of Physics, University of Rhode Island, Kingston, RI, United States
| | - Yana K. Reshetnyak
- Department of Physics, University of Rhode Island, Kingston, RI, United States
| | - Jason S. Lewis
- Department of Radiology and the Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States
- Department of Radiology, Weill Cornell Medical College, New York, NY, United States
- Department of Pharmacology Program, Weill Cornell Medical College, New York, NY, United States
| |
Collapse
|
15
|
Tronchin S, Forster JC, Hickson K, Bezak E. Dosimetry in targeted alpha therapy. A systematic review: current findings and what is needed. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac5fe0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 03/22/2022] [Indexed: 12/13/2022]
Abstract
Abstract
Objective. A systematic review of dosimetry in Targeted Alpha Therapy (TAT) has been performed, identifying the common issues. Approach. The systematic review was performed in accordance with the PRISMA guidelines, and the literature was searched using the Scopus and PubMed databases. Main results. From the systematic review, three key points should be considered when performing dosimetry in TAT. (1) Biodistribution/Biokinetics: the accuracy of the biodistribution data is a limit to accurate dosimetry in TAT. The biodistribution of alpha-emitting radionuclides throughout the body is difficult to image directly, with surrogate radionuclide imaging, blood/faecal sampling, and animal studies able to provide information. (2) Daughter radionuclides: the decay energy of the alpha-emissions is sufficient to break the bond to the targeting vector, resulting in a release of free daughter radionuclides in the body. Accounting for daughter radionuclide migration is essential. (3) Small-scale dosimetry and microdosimetry: due to the short path length and heterogeneous distribution of alpha-emitters at the target site, small-scale/microdosimetry are important to account for the non-uniform dose distribution in a target region, organ or cell and for assessing the biological effect of alpha-particle radiation. Significance. TAT is a form of cancer treatment capable of delivering a highly localised dose to the tumour environment while sparing the surrounding healthy tissue. Dosimetry is an important part of treatment planning and follow up. Being able to accurately predict the radiation dose to the target region and healthy organs could guide the optimal prescribed activity. Detailed dosimetry models accounting for the three points mentioned above will help give confidence in and guide the clinical application of alpha-emitting radionuclides in targeted cancer therapy.
Collapse
|
16
|
Principles and Applications of Auger-Electron Radionuclide Therapy. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00040-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
17
|
Carter LM, Ocampo Ramos JC, Kesner AL. Personalized dosimetry of 177Lu-DOTATATE: a comparison of organ- and voxel-level approaches using open-access images. Biomed Phys Eng Express 2021; 7. [PMID: 34271565 DOI: 10.1088/2057-1976/ac1550] [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: 05/17/2021] [Accepted: 07/16/2021] [Indexed: 11/11/2022]
Abstract
177Lu-DOTATATE (Lutathera®) enables targeted radionuclide therapy of neuroendocrine tumors expressing somatostatin receptor type 2. Though patient-specific dosimetry estimates may be clinically important for predicting absorbed dose-effect relationships, there are multiple relevant dosimetry paradigms which are distinct in terms of clinical effort, numerical output and added-value. This work compares three different approaches for177Lu-DOTATATE dosimetry, including 1) an organ-level approach based on reference phantom MIRD S-values scaled to patient-specific organ masses (MIRDcalc), 2) an organ-level approach based on Monte Carlo simulation in a patient-specific mesh phantoms (PARaDIM), and 3) a 3D approach based on Monte Carlo simulation in patient-specific voxel phantoms.Method. Serial quantitative SPECT/CT images for two patients receiving177Lu-DOTATATE therapy were obtained from archive in theDeep Bluedatabase. For each patient, the serial CT images were co-registered to the first time point CT using a deformable registration technique aided by virtual landmarks placed in the kidney pelves and the lesion foci. The co-registered SPECT images were integrated voxel-wise to generate time-integrated activity maps. Lesions, kidneys, liver, spleen, lungs, compact bone, spongiosa, and rest of body were segmented at the first imaging time point and overlaid on co-registered integrated activity maps. The resultant segmentation was used for three purposes: 1) to generate patient-specific phantoms, 2) to determine organ-level time-integrated activities, and 3) to generate dose volume histograms from 3D voxel-based calculations.Results. Mean absorbed doses were computed for lesions and 48 tissues with MIRDcalc software. Mean organ absorbed doses and dose volume histograms were obtained for lesions and 6 tissues with the voxel Monte Carlo approach. Lesion- and organ-level absorbed dose estimates agreed within ±26% for the lesions and ±13% for the critical organs, among the different methods tested. Overall good agreement was observed with the dosimetry estimates from the NETTER-1 trial.Conclusions. For personalized177Lu-DOTATATE dosimetry, a combined approach was determined to be valuable, which utilized two dose calculation methods supported by a single image processing workflow. In the absence of quantitative imaging limitations, the voxel Monte Carlo method likely provides valuable information to guide treatment by considering absorbed dose non-uniformity in lesions and organs at risk. The patient-scaled reference phantom method also provides valuable information, including absorbed dose estimates for non-segmented organs, and more accurate dose estimates for complex radiosensitive organs including the active marrow.
Collapse
Affiliation(s)
- L M Carter
- Deparment of Medical Physics, Memorial Sloan Kettering Cancer Center, NY, 10065, United States of America
| | - J C Ocampo Ramos
- Deparment of Medical Physics, Memorial Sloan Kettering Cancer Center, NY, 10065, United States of America
| | - A L Kesner
- Deparment of Medical Physics, Memorial Sloan Kettering Cancer Center, NY, 10065, United States of America
| |
Collapse
|
18
|
Medical application of particle and heavy ion transport code system PHITS. Radiol Phys Technol 2021; 14:215-225. [PMID: 34195914 DOI: 10.1007/s12194-021-00628-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/18/2021] [Accepted: 06/21/2021] [Indexed: 12/15/2022]
Abstract
The Particle and Heavy Ion Transport code System (PHITS) is a general-purpose Monte Carlo simulation code that has been applied in various areas of medical physics. These include application in different types of radiotherapy, shielding calculations, application to radiation biology, and research and development of medical tools. In this article, the useful features of PHITS are explained by referring to actual examples of various medical applications.
Collapse
|
19
|
Carter LM, Choi C, Krebs S, Beattie BJ, Kim CH, Schoder H, Bolch WE, Kesner AL. Patient Size-Dependent Dosimetry Methodology Applied to 18F-FDG Using New ICRP Mesh Phantoms. J Nucl Med 2021; 62:jnumed.120.256719. [PMID: 33863823 PMCID: PMC8612182 DOI: 10.2967/jnumed.120.256719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 03/16/2021] [Accepted: 03/16/2021] [Indexed: 11/16/2022] Open
Abstract
Despite the known influence of anatomic variability on internal dosimetry, dosimetry for 18F-FDG and other diagnostic radiopharmaceuticals is routinely derived using reference phantoms, which embody population-averaged morphometry for a given age and sex. Moreover, phantom format affects dosimetry estimates to varying extent. Here, we applied newly developed mesh format reference phantoms and a patient-dependent phantom library to assess the impact of height, weight, and body contour variation on dosimetry of 18F-FDG. We compared the mesh reference phantom dosimetry estimates with corresponding estimates from common software to identify differences related to phantom format or software implementation. Our study serves as an example of how more precise patient size-dependent dosimetry methodology could be performed. Methods: Absorbed dose coefficients were computed for the adult mesh reference phantoms and derivative patient-dependent phantom series by Monte Carlo simulation using the PHITS radiation transport code within PARaDIM software. The dose coefficients were compared with reference absorbed dose coefficients obtained from ICRP Publication 128, or generated using software including OLINDA 2.1, OLINDA 1.1, and IDAC-dose 2.1. Results: Differences in dosimetry arising from anatomical variations were shown to be significant, with detriment-weighted dose coefficients for the percentile-specific phantoms varying by up to ±40% relative to the corresponding reference phantom effective dose coefficients, irrespective of phantom format. Similar variations were seen in the individual organ absorbed dose coefficients for the percentile-specific phantoms relative to the reference phantoms. The effective dose coefficient for the mesh reference adult was 0.017 mSv/MBq, which was 5% higher than estimated by a corresponding voxel phantom, and 10% lower than estimated by the stylized phantom format. Conclusion: We observed notable variability in 18F-FDG dosimetry across morphometrically different patients, supporting the use of patient-dependent phantoms for more accurate dosimetric estimations relative to standard reference dosimetry. These data may help in optimizing imaging protocols and research studies, in particular when longer-lived isotopes are employed.
Collapse
Affiliation(s)
- Lukas M. Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Chansoo Choi
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Simone Krebs
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York; and
| | - Bradley J. Beattie
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Chan Hyeong Kim
- Department of Nuclear Engineering, Hanyang University, Seoul, Republic of Korea
| | - Heiko Schoder
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York; and
| | - Wesley E. Bolch
- J. Crayton Pruitt Department of Biomedical Engineering, University of Florida, Gainesville, Florida
| | - Adam L. Kesner
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| |
Collapse
|
20
|
Dacek MM, Veach DR, Cheal SM, Carter LM, McDevitt MR, Punzalan B, Burnes Vargas D, Kubik TZ, Monette S, Santich BH, Yang G, Ouerfelli O, Kesner AL, Cheung NKV, Scheinberg DA, Larson SM, Krebs S. Engineered Cells as a Test Platform for Radiohaptens in Pretargeted Imaging and Radioimmunotherapy Applications. Bioconjug Chem 2021; 32:649-654. [PMID: 33819023 DOI: 10.1021/acs.bioconjchem.0c00595] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pretargeted imaging and radioimmunotherapy approaches are designed to have superior targeting properties over directly targeted antibodies but impose more complex pharmacology, which hinders efforts to optimize the ligands prior to human applications. Human embryonic kidney 293T cells expressing the humanized single-chain variable fragment (scFv) C825 (huC825) with high-affinity for DOTA-haptens (293T-huC825) in a transmembrane-anchored format eliminated the requirement to use other pretargeting reagents and provided a simplified, accelerated assay of radiohapten capture while offering normalized cell surface expression of the molecular target of interest. Using binding assays, ex vivo biodistribution, and in vivo imaging, we demonstrated that radiohaptens based on benzyl-DOTA and a second generation "Proteus" DOTA-platform effectively and specifically engaged membrane-bound huC825, achieving favorable tumor-to-normal tissue uptake ratios in mice. Furthermore, [86Y]Y-DOTA-Bn predicted absorbed dose to critical organs with reasonable accuracy for both [177Lu]Lu-DOTA-Bn and [225Ac]Ac-Pr, which highlights the benefit of a dosimetry-based treatment approach.
Collapse
Affiliation(s)
- Megan M Dacek
- Molecular Pharmacology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Department of Pharmacology, Weill Cornell Medical College, New York, New York 10065, United States
| | - Darren R Veach
- Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Radiochemistry and Imaging Sciences Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Department of Radiology, Weill Cornell Medical College, New York, New York 10065, United States
| | - Sarah M Cheal
- Molecular Pharmacology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Lukas M Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Michael R McDevitt
- Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Department of Radiology, Weill Cornell Medical College, New York, New York 10065, United States
| | - Blesida Punzalan
- Molecular Pharmacology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Daniela Burnes Vargas
- Molecular Pharmacology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Thomas Z Kubik
- Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Sebastien Monette
- Tri-Institutional Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medicine, and The Rockefeller University, New York, New York 10065, United States
| | - Brian H Santich
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Guangbin Yang
- Organic Synthesis Core Facility, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Ouathek Ouerfelli
- Organic Synthesis Core Facility, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Adam L Kesner
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - Nai-Kong V Cheung
- Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States
| | - David A Scheinberg
- Molecular Pharmacology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Department of Pharmacology, Weill Cornell Medical College, New York, New York 10065, United States
| | - Steven M Larson
- Molecular Pharmacology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Department of Radiology, Weill Cornell Medical College, New York, New York 10065, United States
| | - Simone Krebs
- Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, United States.,Department of Radiology, Weill Cornell Medical College, New York, New York 10065, United States
| |
Collapse
|
21
|
Carter LM, Camilo Ocampo Ramos J, Bolch WE, Lewis JS, Kesner AL. Technical Note: Patient-morphed mesh-type phantoms to support personalized nuclear medicine dosimetry - a proof of concept study. Med Phys 2021; 48:2018-2026. [PMID: 33595863 DOI: 10.1002/mp.14784] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 01/03/2021] [Accepted: 02/12/2021] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Current standard practice for clinical radionuclide dosimetry utilizes reference phantoms, where defined organ dimensions represent population averages for a given sex and age. Greater phantom personalization would support more accurate dose estimations and personalized dosimetry. Tailoring phantoms is traditionally accomplished using operator-intensive organ-level segmentation of anatomic images. Modern mesh phantoms provide enhanced anatomical realism, which has motivated their integration within Monte Carlo codes. Here, we present an automatable strategy for generating patient-specific phantoms/dosimetry using intensity-based deformable image registration between mesh reference phantoms and patient CT images. This work demonstrates a proof-of-concept personalized dosimetry workflow, presented in comparison to the manual segmentation approach. METHODS A linear attenuation coefficient phantom was generated by resampling the PSRK-Man reference phantom onto a voxel grid and defining organ regions with corresponding Hounsfield unit (HU) reference values. The HU phantom was co-registered with a patient CT scan using Plastimatch B-spline deformable registration. In parallel, major organs were manually contoured to generate a "ground truth" patient-specific phantom for comparisons. Monte Carlo derived S-values, which support nuclear medicine dosimetry, were calculated using both approaches and compared. RESULTS Application of the derived B-spline transform to the polygon vertices comprising the PSRK-Man yielded a deformed variant more closely matching the patient's body contour and most organ volumes as-evaluated by Hausdorff distance and Dice metrics. S-values computed for fluorine-18 for the deformed phantom using the Particle and Heavy Ion Transport code System showed improved agreement with those derived from the patient-specific analog. CONCLUSIONS Deformable registration techniques can be used to create a personalized phantom and better support patient-specific dosimetry. This method is shown to be easier and faster than manual segmentation. Our study is limited to a proof-of-concept scope, but demonstrates that integration of personalized phantoms into clinical dosimetry workflows can reasonably be achieved when anatomical images (CT) are available.
Collapse
Affiliation(s)
- Lukas M Carter
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | | | - Wesley E Bolch
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
| | - Jason S Lewis
- Department of Radiology, Program in Pharmacology and the Radiochemistry and Molecular Imaging Probes Core, Memorial Sloan Kettering Cancer Center, New York, NY, USA.,Department of Radiology and Department of Pharmacology, Weill Cornell Medical College, New York, NY, USA
| | - Adam L Kesner
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| |
Collapse
|
22
|
Sato T, Furuta T, Liu Y, Naka S, Nagamori S, Kanai Y, Watabe T. Individual dosimetry system for targeted alpha therapy based on PHITS coupled with microdosimetric kinetic model. EJNMMI Phys 2021; 8:4. [PMID: 33432383 PMCID: PMC7801536 DOI: 10.1186/s40658-020-00350-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 12/21/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND An individual dosimetry system is essential for the evaluation of precise doses in nuclear medicine. The purpose of this study was to develop a system for calculating not only absorbed doses but also EQDX(α/β) from the PET-CT images of patients for targeted alpha therapy (TAT), considering the dose dependence of the relative biological effectiveness, the dose-rate effect, and the dose heterogeneity. METHODS A general-purpose Monte Carlo particle transport code PHITS was employed as the dose calculation engine in the system, while the microdosimetric kinetic model was used for converting the absorbed dose to EQDX(α/β). PHITS input files for describing the geometry and source distribution of a patient are automatically created from PET-CT images, using newly developed modules of the radiotherapy package based on PHITS (RT-PHITS). We examined the performance of the system by calculating several organ doses using the PET-CT images of four healthy volunteers after injecting 18F-NKO-035. RESULTS The deposition energy map obtained from our system seems to be a blurred image of the corresponding PET data because annihilation γ-rays deposit their energies rather far from the source location. The calculated organ doses agree with the corresponding data obtained from OLINDA 2.0 within 20%, indicating the reliability of our developed system. Test calculations by replacing the labeled radionuclide from 18F to 211At suggest that large dose heterogeneity in a target volume is expected in TAT, resulting in a significant decrease of EQDX(α/β) for higher-activity injection. CONCLUSIONS As an extension of RT-PHITS, an individual dosimetry system for nuclear medicine was developed based on PHITS coupled with the microdosimetric kinetic model. It enables us to predict the therapeutic and side effects of TAT based on the clinical data largely available from conventional external radiotherapy.
Collapse
Affiliation(s)
- Tatsuhiko Sato
- Nuclear Science and Engineering Center, Japan Atomic Energy Agency, Shirakata 2-4, Tokai, Ibaraki, 319-1195, Japan.
- Research Center for Nuclear Physics, Osaka University, Suita, Japan.
| | - Takuya Furuta
- Nuclear Science and Engineering Center, Japan Atomic Energy Agency, Shirakata 2-4, Tokai, Ibaraki, 319-1195, Japan
| | - Yuwei Liu
- Department of Nuclear Medicine and Tracer Kinetics, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Sadahiro Naka
- Department of Radiology, Osaka University Hospital, Suita, Japan
| | - Shushi Nagamori
- Department of Laboratory Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Yoshikatsu Kanai
- Department of Bio-system Pharmacology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Tadashi Watabe
- Department of Nuclear Medicine and Tracer Kinetics, Graduate School of Medicine, Osaka University, Suita, Japan
| |
Collapse
|
23
|
Hanaoka K, Miyaji N, Yoneyama H, Ogawa M, Maeda T, Sakaguchi K, Iimori T, Tsushima H. [Radiological Technology for Targeted Radionuclide Therapy]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2020; 76:1237-1247. [PMID: 33342942 DOI: 10.6009/jjrt.2020_jsrt_76.12.1237] [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: 11/11/2022]
Abstract
Targeted radioisotope therapy (TRT) is a radiotherapy using radioisotope or drug incorporating it and has been used as a treatment for selectively irradiating cancer cells. In recent years, interest in TRT has increased due to improvements in radionuclide production technology, development of new drugs and imaging modalities, and improvements in radiation technology. In order to enhance the effect of TRT, measurement of individual radiation doses to tumor tissue and organs at risk is important using highly quantitative nuclear medicine images. In this paper, we present a review of literature on optimization of TRT, which is a new research area from the perspective of radiation technology.
Collapse
Affiliation(s)
- Kohei Hanaoka
- Institute of Advanced Clinical Medicine, Kindai University
| | - Noriaki Miyaji
- Department of Nuclear Medicine, Cancer Institute Hospital of Japanese Foundation for Cancer Research
| | - Hiroto Yoneyama
- Department of Radiological Technology, Kanazawa University Hospital
| | | | - Takamasa Maeda
- Radiological Technology Section, QST Hospital, National Institutes for Quantum and Radiological Science and Technology
| | | | | | - Hiroyuki Tsushima
- Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences
| |
Collapse
|
24
|
Howell RW. Advancements in the use of Auger electrons in science and medicine during the period 2015-2019. Int J Radiat Biol 2020; 99:2-27. [PMID: 33021416 PMCID: PMC8062591 DOI: 10.1080/09553002.2020.1831706] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/01/2020] [Accepted: 09/28/2020] [Indexed: 02/06/2023]
Abstract
Auger electrons can be highly radiotoxic when they are used to irradiate specific molecular sites. This has spurred basic science investigations of their radiobiological effects and clinical investigations of their potential for therapy. Focused symposia on the biophysical aspects of Auger processes have been held quadrennially. This 9th International Symposium on Physical, Molecular, Cellular, and Medical Aspects of Auger Processes at Oxford University brought together scientists from many different fields to review past findings, discuss the latest studies, and plot the future work to be done. This review article examines the research in this field that was published during the years 2015-2019 which corresponds to the period since the last meeting in Japan. In addition, this article points to future work yet to be done. There have been a plethora of advancements in our understanding of Auger processes. These advancements range from basic atomic and molecular physics to new ways to implement Auger electron emitters in radiopharmaceutical therapy. The highly localized doses of radiation that are deposited within a 10 nm of the decay site make them precision tools for discovery across the physical, chemical, biological, and medical sciences.
Collapse
Affiliation(s)
- Roger W Howell
- Division of Radiation Research, Department of Radiology, New Jersey Medical School, Rutgers University, Newark, NJ, USA
| |
Collapse
|
25
|
Pirovano G, Jannetti SA, Carter LM, Sadique A, Kossatz S, Guru N, Demétrio De Souza França P, Maeda M, Zeglis BM, Lewis JS, Humm JL, Reiner T. Targeted Brain Tumor Radiotherapy Using an Auger Emitter. Clin Cancer Res 2020; 26:2871-2881. [PMID: 32066626 PMCID: PMC7299758 DOI: 10.1158/1078-0432.ccr-19-2440] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 10/07/2019] [Accepted: 02/12/2020] [Indexed: 12/20/2022]
Abstract
PURPOSE Glioblastoma multiforme is a highly aggressive form of brain cancer whose location, tendency to infiltrate healthy surrounding tissue, and heterogeneity significantly limit survival, with scant progress having been made in recent decades. EXPERIMENTAL DESIGN 123I-MAPi (Iodine-123 Meitner-Auger PARP1 inhibitor) is a precise therapeutic tool composed of a PARP1 inhibitor radiolabeled with an Auger- and gamma-emitting iodine isotope. Here, the PARP inhibitor, which binds to the DNA repair enzyme PARP1, specifically targets cancer cells, sparing healthy tissue, and carries a radioactive payload within reach of the cancer cells' DNA. RESULTS The high relative biological efficacy of Auger electrons within their short range of action is leveraged to inflict DNA damage and cell death with high precision. The gamma ray emission of 123I-MAPi allows for the imaging of tumor progression and therapy response, and for patient dosimetry calculation. Here we demonstrated the efficacy and specificity of this small-molecule radiotheranostic in a complex preclinical model. In vitro and in vivo studies demonstrate high tumor uptake and a prolonged survival in mice treated with 123I-MAPi when compared with vehicle controls. Different methods of drug delivery were investigated to develop this technology for clinical applications, including convection enhanced delivery and intrathecal injection. CONCLUSIONS Taken together, these results represent the first full characterization of an Auger-emitting PARP inhibitor which demonstrate a survival benefit in mouse models of GBM and confirm the high potential of 123I-MAPi for clinical translation.
Collapse
Affiliation(s)
- Giacomo Pirovano
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Stephen A Jannetti
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Biochemistry, Hunter College, The City University of New York (CUNY), New York, New York
- PhD Program in Biochemistry, The Graduate Center, The City University of New York (CUNY), New York, New York
| | - Lukas M Carter
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Ahmad Sadique
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Susanne Kossatz
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Navjot Guru
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | | | - Masatomo Maeda
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Brian M Zeglis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Chemistry, Hunter College, The City University of New York (CUNY), New York, New York
- Department of Radiology, Weill Cornell Medical College, New York, New York
- PhD Program in Chemistry, The Graduate Center, The City University of New York (CUNY), New York, New York
| | - Jason S Lewis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Radiology, Weill Cornell Medical College, New York, New York
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York
- Department of Pharmacology, Weill Cornell Medical College, New York, New York
| | - John L Humm
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Thomas Reiner
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York.
- Department of Radiology, Weill Cornell Medical College, New York, New York
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| |
Collapse
|
26
|
Frezza A, Joachim-Paquet C, Chauvin M, Després P. Validation of irtGPUMCD, a GPU-based Monte Carlo internal dosimetry framework for radionuclide therapy. Phys Med 2020; 73:95-104. [PMID: 32334403 DOI: 10.1016/j.ejmp.2020.04.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 04/07/2020] [Accepted: 04/12/2020] [Indexed: 11/28/2022] Open
Abstract
PURPOSE Monte Carlo (MC) simulations are highly desirable for dose treatment planning and evaluation in radiation oncology. This is true also in emerging nuclear medicine applications such as internal radiotherapy with radionuclides. The purpose of this study is the validation of irtGPUMCD, a GPU-based MC code for dose calculations in internal radiotherapy. METHODS The female and male phantoms of the International Commission on Radiological Protection (ICRP 110) were used as benchmarking geometries for this study focused on 177Lu and including 99mTc and 131I. Dose calculations were also conducted for a real patient. For phantoms, twelve anatomical structures were considered as target/source organs. The S-values were evaluated with irtGPUMCD simulations (108 photons), with gamma branching ratios of ICRP 107 publication. The 177Lu electrons S-values were calculated for source organs only, based on local deposition of dose in irtGPUMCD. The S-value relative difference between irtGPUMCD and IDAC-DOSE were evaluated for all targets/sources considered. A DVHs comparison with GATE was conducted. An exponential track length estimator was introduced in irtGPUMCD to increase computational efficiency. RESULTS The relative S-value differences between irtGPUMCD and IDAC-DOSE were <5% while this comparison with GATE was <1%. The DVHs dosimetric indices comparison between GATE and irtGPUMCD for the patient led to an excellent agreement (<2%). The time required for the simulation of 108 photons was 1.5 min for the female phantom, and one minute for the real patient (<1% uncertainty). These results are promising and let envision the use of irtGPUMCD for internal dosimetry in clinical applications.
Collapse
Affiliation(s)
- Andrea Frezza
- Department of Physics, Engineering Physics and Optics and Cancer Research Center, Université Laval, Quebec City, QC G1V 0A6, Canada
| | - Charles Joachim-Paquet
- Department of Physics, Engineering Physics and Optics and Cancer Research Center, Université Laval, Quebec City, QC G1V 0A6, Canada
| | - Maxime Chauvin
- CRCT, UMR 1037, Inserm, Université Toulouse III Paul Sabatier, Toulouse, France
| | - Philippe Després
- Department of Physics, Engineering Physics and Optics and Cancer Research Center, Université Laval, Quebec City, QC G1V 0A6, Canada; Department of Radiation Oncology and Research Center of CHU de Québec - Université Laval, Quebec City, QC G1R 2J6, Canada.
| |
Collapse
|