UNLABELLED: (99m)Tc-hydrazinonicotinamide-Tyr(3)-octreotide ((99m)Tc-HYNIC-TOC) is increasingly gaining acceptance as a new radiopharmaceutical for the diagnosis of pathologic lesions overexpressing somatostatin receptors. However, little information has been published about the radiation dosimetry of this agent. The aim of this study was to assess the biodistribution and radiation dosimetry of commercially available (99m)Tc-HYNIC-TOC. A dose calculation procedure designed to be feasible to implement in a busy clinical environment was used. METHODS: Twenty-eight patients were imaged for suspected neuroendocrine tumors using a series of whole-body planar, dynamic planar, and SPECT/CT studies, after injection with (99m)Tc-HYNIC-TOC. Patient-specific dosimetry was performed using the OLINDA/EXM software with time-integrated activity coefficients estimated from a hybrid planar/SPECT technique. A phantom experiment was performed to establish adaptive thresholds for determination of source region volumes and activities. RESULTS: Pathologic uptake, diagnosed as due to neuroendocrine tumors, was observed in 12 patients. Normal organs with significant uptake included the kidneys, liver, and spleen. The mean effective dose after (99m)Tc-HYNIC-TOC injection was 4.6 ± 1.1 mSv. Average normal-organ doses were 0.030 ± 0.012, 0.021 ± 0.007, and 0.012 ± 0.005 mGy/MBq for the spleen, kidneys, and liver, respectively. The interpatient kidney dose ranged from 0.011 to 0.039 mGy/MBq, whereas the range of tumor doses varied from 0.003 to 0.053 mGy/MBq. The ratio of tumor to kidney dose ranged from 0.13 to 2.9. The optimal thresholds for recovery of true activity in the phantom study were significantly lower than those used for volume determination. CONCLUSION: The patient-specific 3-dimensional dosimetry protocol used in this study is a clinically feasible technique that has been applied to demonstrate large dose variations in tumors and normal organs between patients imaged with (99m)Tc-HYNIC-TOC.
UNLABELLED: (99m)Tc-hydrazinonicotinamide-Tyr(3)-octreotide ((99m)Tc-HYNIC-TOC) is increasingly gaining acceptance as a new radiopharmaceutical for the diagnosis of pathologic lesions overexpressing somatostatin receptors. However, little information has been published about the radiation dosimetry of this agent. The aim of this study was to assess the biodistribution and radiation dosimetry of commercially available (99m)Tc-HYNIC-TOC. A dose calculation procedure designed to be feasible to implement in a busy clinical environment was used. METHODS: Twenty-eight patients were imaged for suspected neuroendocrine tumors using a series of whole-body planar, dynamic planar, and SPECT/CT studies, after injection with (99m)Tc-HYNIC-TOC. Patient-specific dosimetry was performed using the OLINDA/EXM software with time-integrated activity coefficients estimated from a hybrid planar/SPECT technique. A phantom experiment was performed to establish adaptive thresholds for determination of source region volumes and activities. RESULTS: Pathologic uptake, diagnosed as due to neuroendocrine tumors, was observed in 12 patients. Normal organs with significant uptake included the kidneys, liver, and spleen. The mean effective dose after (99m)Tc-HYNIC-TOC injection was 4.6 ± 1.1 mSv. Average normal-organ doses were 0.030 ± 0.012, 0.021 ± 0.007, and 0.012 ± 0.005 mGy/MBq for the spleen, kidneys, and liver, respectively. The interpatient kidney dose ranged from 0.011 to 0.039 mGy/MBq, whereas the range of tumor doses varied from 0.003 to 0.053 mGy/MBq. The ratio of tumor to kidney dose ranged from 0.13 to 2.9. The optimal thresholds for recovery of true activity in the phantom study were significantly lower than those used for volume determination. CONCLUSION: The patient-specific 3-dimensional dosimetry protocol used in this study is a clinically feasible technique that has been applied to demonstrate large dose variations in tumors and normal organs between patients imaged with (99m)Tc-HYNIC-TOC.
Authors: David Taïeb; Rodney J Hicks; Elif Hindié; Benjamin A Guillet; Anca Avram; Pietro Ghedini; Henri J Timmers; Aaron T Scott; Saeed Elojeimy; Domenico Rubello; Irène J Virgolini; Stefano Fanti; Sona Balogova; Neeta Pandit-Taskar; Karel Pacak Journal: Eur J Nucl Med Mol Imaging Date: 2019-06-29 Impact factor: 9.236
Authors: David Taïeb; Henri J Timmers; Elif Hindié; Benjamin A Guillet; Hartmut P Neumann; Martin K Walz; Giuseppe Opocher; Wouter W de Herder; Carsten C Boedeker; Ronald R de Krijger; Arturo Chiti; Adil Al-Nahhas; Karel Pacak; Domenico Rubello Journal: Eur J Nucl Med Mol Imaging Date: 2012-08-28 Impact factor: 9.236
Authors: Andrew P Robinson; Jill Tipping; David M Cullen; David Hamilton; Richard Brown; Alex Flynn; Christopher Oldfield; Emma Page; Emlyn Price; Andrew Smith; Richard Snee Journal: EJNMMI Phys Date: 2016-07-13
Authors: Anna Sowa-Staszczak; Dorota Pach; Renata Mikołajczak; Helmut Mäcke; Agata Jabrocka-Hybel; Agnieszka Stefańska; Monika Tomaszuk; Barbara Janota; Aleksandra Gilis-Januszewska; Maciej Małecki; Grzegorz Kamiński; Aldona Kowalska; Jan Kulig; Andrzej Matyja; Czesław Osuch; Alicja Hubalewska-Dydejczyk Journal: Eur J Nucl Med Mol Imaging Date: 2012-12-07 Impact factor: 9.236
Authors: Mehdi Momennezhad; Shahrokh Nasseri; Seyed Rasoul Zakavi; Ali Asghar Parach; Mahdi Ghorbani; Ruhollah Ghahraman Asl Journal: World J Nucl Med Date: 2016 May-Aug