Biodistribution and internal radiation dosimetry of a companion diagnostic radiopharmaceutical, [68Ga]PSMA-11, in subcutaneous prostate cancer xenograft model mice

Abstract Objective Patients with advanced prostate cancer are suitable candidates for [177Lu]PSMA-617 therapy. Integrated SPECT/CT systems have the potential to improve the accuracy of patient-specific tumor dosimetry. We present a novel patient-specific Monte Carlo based voxel-wise dosimetry approach to determine organ and total tumor doses (TTD). Methods 13 patients with histologically confirmed metastasized castration-resistant prostate cancer were treated with a total of 18 cycles of [177Lu]PSMA-617 therapy. In each patient, dosimetry was performed after the first cycle of [177Lu]PSMA-617 therapy. Regions of interest were defined manually on the SPECT/CT images for the kidneys, spleen and all 295 PSMA-positive tumor lesions in the field of view. The absorbed dose to normal organs and to all tumor lesions were calculated by a three dimensional dosimetry method based on Monte Carlo Simulations. Results The average dose values yielded the following results: 2.59 ± 0.63 Gy (1.67–3.92 Gy) for the kidneys, 0.79 ± 0.46 Gy (0.31–1.90 Gy) for the spleen and 11.00 ± 11.97 Gy (1.28–49.10 Gy) for all tracer-positive tumor lesions. A trend towards higher TTD was observed in patients with Gleason Scores > 8 compared to Gleason Scores ≤ 8 and in lymph node metastases compared to bone metastases. A significant correlation was determined between the serum-PSA level before RLT and the TTD (r = –0.57, p < 0.05), as well as between the TTD with the percentage change of serum-PSA levels before and after therapy was observed (r = –0.57, p < 0.05). Patients with higher total tumor volumes of PSMA-positive lesions demonstrated significantly lower kidney average dose values (r = –0.58, p < 0.05). Conclusion The presented novel Monte Carlo based voxel-wise dosimetry calculates a patient specific whole-body dose distribution, thus taking into account individual anatomies and tissue compositions showing promising results for the estimation of radiation doses of normal organs and PSMA-positive tumor lesions.

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RadioPharmaDose, a java-based open-source software for estimating and reporting internal radiation doses

Applied Computing and Informatics ◽

10.1016/j.aci.2018.06.001 ◽

2018 ◽

Vol 16 (1/2) ◽

pp. 259-266

Author(s):

Jaafar EL Bakkali ◽

Hamid Mansouri ◽

Abderrahim Doudouh

Keyword(s):

Open Source ◽

Open Source Software ◽

Radiation Dosimetry ◽

Absorbed Dose ◽

Radiological Protection ◽

Internal Radiation ◽

Dosimetric Data ◽

Sqlite Database ◽

User Friendly ◽

Friendly Graphical User Interface

In this work, a user-friendly Java-based open-source software has been developed for internal radiation dosimetry. Based on values published by the International Commission on Radiological Protection (ICRP), the software calculates the estimated absorbed dose for each organ and also the estimated effective dose, this for about forty of the most known radioactive drugs. In addition, the present software offers many features which include: 1) a very friendly graphical user-interface (GUI) designed to facilitate the process of selecting mandatory input data such as radiopharmaceutical product, administered activity and patient's data, 2) a tool for generating a medical report, which can be exported as PDF file or printed directly and then incorporated into the patient's record, 3) a SQLite database for storing patient's specific and dosimetric data. We believe that the present software can be a useful tool for nuclear medicine workers. It is freely available for download on GitHub (https://github.com/EL-Bakkali-Jaafar/RadioPharmaDose).

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Radiation Dosimetry for 177 Lu-PSMA I&T in Metastatic Castration-Resistant Prostate Cancer: Absorbed Dose in Normal Organs and Tumor Lesions

Journal of Nuclear Medicine ◽

10.2967/jnumed.116.178483 ◽

2016 ◽

Vol 58 (3) ◽

pp. 445-450 ◽

Cited By ~ 43

Author(s):

Shozo Okamoto ◽

Anne Thieme ◽

Jakob Allmann ◽

Calogero D’Alessandria ◽

Tobias Maurer ◽

...

Keyword(s):

Prostate Cancer ◽

Radiation Dosimetry ◽

Absorbed Dose ◽

Castration Resistant Prostate Cancer ◽

Castration Resistant

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Evaluation of Radiation dosimetry of 99mTc-HYNIC-PSMA and imaging in prostate cancer

Scientific Reports ◽

10.1038/s41598-020-61129-5 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Jianping Zhang ◽

Jiangang Zhang ◽

Xiaoping Xu ◽

Linjun Lu ◽

Silong Hu ◽

...

Keyword(s):

Prostate Cancer ◽

Radiation Dosimetry ◽

Tumor Imaging ◽

Absorbed Dose ◽

Ct Images ◽

Tracer Uptake ◽

Whole Body ◽

Imaging Method ◽

Absorbed Doses ◽

Total Body

Abstract This study aims to evaluate the radiation dosimetry of a new technetium-99m‒labelled small-molecule inhibitor of prostate-specific membrane antigen (HYNIC-Glu-Urea-A, 99mTc-HYNIC-PSMA) and its feasibility as a tumor-imaging agent in prostate cancer (PCa) patients. A total of 15 PCa patients were enrolled in this study. For the dosimetry study, 5 PCa patients received whole-body planar scans at 0.5 h, 1 h, 2 h, 4 h and 8 h after 99mTc-HYNIC-PSMA injection. The Dosimetry Toolkit (GE, Milwaukee) was used to process the data and segment the organs in the SPECT/CT images, which were then projected onto planar images. The organ-specific absorbed doses, total-body absorbed doses and 99mTc-HYNIC-PSMA effective doses of patients were calculated using OLINDA/EXM 1.1 software. Whole-body SPECT/CT images were also acquired from additional 10 prostate patients to investigate the feasibility of 99mTc-HYNIC-PSMA for imaging tumors by calculating the ratio of tumor-to-background tracer uptake at 2 h after 740 MBq administration. The total-body absorbed dose was 1.54E-03 ± 2.43E-04 mGy/MBq, and the effective dose was 3.72E-03 ± 4.5E-04 mSv/MBq. Compared to published studies of other similar PSMA tracers and 99mTc-targeted conventional tracers, the absorbed doses of 99mTc-HYNIC-PSMA in all organs showed that it could be used safely in the human body. In addition, 99mTc-HYNIC-PSMA showed high tracer uptake (with a tumor-to-background ratio of 9.42 ± 2.62) in the malignant lesions of PCa patients, making it a promising radiopharmaceutical imaging method for site-specific management of PCa.

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Comparison of the absorbed dose for 99m Tc-diethylenetriaminepentaacetic acid and 99m Tc-ethylenedicysteine radiopharmaceuticals using medical internal radiation dosimetry

Journal of Medical Signals & Sensors ◽

10.4103/2228-7477.161489 ◽

2015 ◽

Vol 5 (3) ◽

pp. 171 ◽

Cited By ~ 2

Author(s):

Masoud Moslehi ◽

Shokufeh Pirdamooie ◽

Ahmad Shanei

Keyword(s):

Radiation Dosimetry ◽

Absorbed Dose ◽

Diethylenetriaminepentaacetic Acid ◽

Internal Radiation

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Internal Radiation Dose Assessment in Nuclear Medicine Practices by Using Locally Developed IRDE Software

Bangladesh Journal of Nuclear Medicine ◽

10.3329/bjnm.v21i1.40249 ◽

2019 ◽

Vol 21 (1) ◽

pp. 26-30

Author(s):

Abdus Sattar Mollah ◽

Mohammad Ruhul Quddus ◽

Sayeed Mohammad Iqubal

Keyword(s):

Nuclear Medicine ◽

Radiation Dosimetry ◽

Absorbed Dose ◽

Dose Calculation ◽

The Body ◽

Dose Assessment ◽

Graphic User Interface ◽

Internal Radiation ◽

Calculation Methodology ◽

Bangladeshi Population

In nuclear medicine practices, internal radiation dosimetry offers methods for calculation of radiation absorbed dose and risks from radionuclides incorporated inside the body. To manually perform internal radiation dosimetry is time-consuming and errors can occur in each step leading to developing software tools to ease users. There are many software packages available; however, many of them have limited functions. Locally developed IRDE software has been used to calculate the absorbed dose per unit of radioactivity in the target organ. The dose calculation methodology in nuclear medicine practices is described in this study along with a preliminary result on dose calculation for Bangladeshi population due to ingestion of 131I radioisotope in nuclear medicine practices. IRDE is user-friendly, graphic user interface-based software. It can be performed all steps of internal dosimetry within single environment lead to reducing calculation time and reducing possibility of error. IRDE also provides fast and accurate results which may be useful for a routine work in nuclear medicine facilities. Bangladesh J. Nuclear Med. 21(1): 26-30, January 2018

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Quantitative comparison of pre-treatment predictive and post-treatment measured dosimetry for selective internal radiation therapy using cone-beam CT for tumor and liver perfusion territory definition

10.21203/rs.3.rs-17076/v1 ◽

2020 ◽

Author(s):

Esmaeel Jafargholi Rangraz ◽

Xikai Tang ◽

Geert Maleux ◽

Jeroen Dekervel ◽

Eric Van Cutsem ◽

...

Keyword(s):

Radiation Therapy ◽

Liver Perfusion ◽

Specific Treatment ◽

Absorbed Dose ◽

Post Treatment ◽

Patient Specific ◽

Selective Internal Radiation Therapy ◽

Internal Radiation ◽

Selective Internal Radiation ◽

Internal Radiation Therapy

Abstract Background: Selective internal radiation therapy (SIRT) is a promising treatment for unresectable hepatic malignancies. Predictive dose calculation based on a simulation using technetium-99m-labeled macro-aggregated albumin ( 99m Tc-MAA) before the treatment is considered as a potential tool for patient-specific treatment planning. Post-treatment dose measurement is mainly performed to confirm the planned absorbed dose to the tumor and non-tumor liver volumes. This study compared the predicted and measured absorbed dose distributions. Methods: Thirty-one patients (67 tumors) treated by SIRT with resin microspheres were analyzed. Predicted and delivered absorbed dose was calculated using 99m Tc-MAA-SPECT and 90 Y TOF-PET imaging. The voxel-level dose distribution was derived using the local deposition model. Liver perfusion territories and tumors have been delineated on contrast-enhanced CBCT images, which have been acquired during the 99m Tc-MAA work-up. Several dose-volume histogram (DVH) parameters together with the mean dose for liver perfusion territories, non-tumoral and tumoral compartments were evaluated. Results: A strong correlation between the predicted and measured mean dose for non-tumoral volume was observed (r=0.937). The ratio of measured and predicted mean dose to this volume has a first, second, and third quartile range of 0.83, 1.05, and 1.25. The difference between the measured and predicted mean dose did not exceed 11 Gy. The correlation between predicted and measured mean dose to the tumor was moderate (r=0.623) with a mean difference of -9.3 Gy. The ratio of measured and predicted tumor mean dose had a median of 1.01 with the first and third quartile ranges of 0.58 and 1.59, respectively. Our results suggest that 99m Tc-MAA-based dosimetry could predict under or over dosing of the non-tumoral liver parenchyma for almost all cases. For more than two-thirds of the tumors, a predictive absorbed dose correctly indicated either good tumor dose coverage or under-dosing of the tumor. Conclusion: Our results highlight the predictive value of 99m Tc-MAA-based dose estimation to predict non-tumor liver irradiation, which can be applied to prescribe an optimized activity aiming at avoiding liver toxicity. Predictive dosimetry is also moderately reliable to estimate the tumor absorbed dose.

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Quantitative comparison of pre-treatment predictive and post-treatment measured dosimetry for selective internal radiation therapy using cone-beam CT for tumor and liver perfusion territory definition

10.21203/rs.3.rs-17076/v2 ◽

2020 ◽

Author(s):

Esmaeel Jafargholi Rangraz ◽

Xikai Tang ◽

Charlotte Van Laeken ◽

Geert Maleux ◽

Jeroen Dekervel ◽

...

Keyword(s):

Radiation Therapy ◽

Liver Perfusion ◽

Specific Treatment ◽

Absorbed Dose ◽

Post Treatment ◽

Patient Specific ◽

Selective Internal Radiation Therapy ◽

Internal Radiation ◽

Selective Internal Radiation ◽

Internal Radiation Therapy

Abstract Background: Selective internal radiation therapy (SIRT) is a promising treatment for unresectable hepatic malignancies. Predictive dose calculation based on a simulation using technetium-99m-labeled macro-aggregated albumin ( 99m Tc-MAA) before the treatment is considered as a potential tool for patient-specific treatment planning. Post-treatment dose measurement is mainly performed to confirm the planned absorbed dose to the tumor and non-tumor liver volumes. This study compared the predicted and measured absorbed dose distributions. Methods: Thirty-one patients (67 tumors) treated by SIRT with resin microspheres were analyzed. Predicted and delivered absorbed dose was calculated using 99m Tc-MAA-SPECT and 90 Y TOF-PET imaging. The voxel-level dose distribution was derived using the local deposition model. Liver perfusion territories and tumors have been delineated on contrast-enhanced CBCT images, which have been acquired during the 99m Tc-MAA work-up. Several dose-volume histogram (DVH) parameters together with the mean dose for liver perfusion territories, non-tumoral and tumoral compartments were evaluated. Results: A strong correlation between the predicted and measured mean dose for non-tumoral volume was observed (r=0.937). The ratio of measured and predicted mean dose to this volume has a first, second, and third quartile range of 0.83, 1.05, and 1.25. The difference between the measured and predicted mean dose did not exceed 11 Gy. The correlation between predicted and measured mean dose to the tumor was moderate (r=0.623) with a mean difference of -9.3 Gy. The ratio of measured and predicted tumor mean dose had a median of 1.01 with the first and third quartile ranges of 0.58 and 1.59, respectively. Our results suggest that 99m Tc-MAA-based dosimetry could predict under or over dosing of the non-tumoral liver parenchyma for almost all cases. For more than two-thirds of the tumors, a predictive absorbed dose correctly indicated either good tumor dose coverage or under-dosing of the tumor. Conclusion: Our results highlight the predictive value of 99m Tc-MAA-based dose estimation to predict non-tumor liver irradiation, which can be applied to prescribe an optimized activity aiming at avoiding liver toxicity. Predictive dosimetry is also moderately reliable to estimate the tumor absorbed dose.

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