Seza A Gulec1, Russ A Kuker2,3, Mohammed Goryawala2, Carlos Fernandez4, Rudolfo Perez5, Alina Khan-Ghany6, Ana Apaza6, Evis Harja6, Mack Harrell7. 1. 1 Department of Surgical Oncology, Endocrine Surgery, Florida International University Herbert Wertheim College of Medicine, Miami, Florida. 2. 2 Department of Radiology, University of Miami Miller School of Medicine, Miami, Florida. 3. 3 Division of Nuclear Medicine, University of Miami Miller School of Medicine, Miami, Florida. 4. 4 Department of Radiology, Elite Imaging Center, Miami, Florida. 5. 5 Department of Endocrinology, Thyroid Medical Institute, Miami, Florida. 6. 6 Department of Endocrinology, Chen Medical Associates, Miami, Florida. 7. 7 Department of Endocrinology, Memorial Health Care System, Hollywood, Florida.
Abstract
BACKGROUND: Although radioactive iodine (RAI) imaging/therapy is one of the earliest applications of theranostics, there remain a number of unresolved clinical questions as to the optimization of diagnostic techniques/protocols and improvements in patient-specific treatment planning strategies. The objectives of this study were to determine the imaging characteristics and clinical feasibility of (124)I positron emission tomography/computed tomography (PET/CT) for the determination of extent of disease and evaluation of RAI kinetics in its physiologic and neoplastic distribution in patients with differentiated thyroid cancer (DTC). METHODS: The study was designed as a prospective phase II diagnostic trial of patients with confirmed DTC. Following adequate preparation, patients received 2 mCi (124)I in liquid form and sequential whole-body PET/CT imaging was performed at five time points (2-4 h, 24 ± 6 h, 48 ± 6 h, 72 ± 6 h, and 96 ± 6 h post-administration). All patients who had (124)I imaging subsequently underwent RAI treatment with (131)I, with administered activities ranging from 100 to 300 mCi. Post-treatment scans were obtained 5-7 days after RAI treatment. A by-patient and by-lesion analysis of the (124)I images was performed and compared with the post-treatment (131)I scans as well as F-18 FDG PET/CT images. Quantitative image analysis was also performed to determine the total functional volume (mL), activity per functional volume (μCi/mL), and cumulated activity (μCi/h) for remnants, salivary glands, and nodal metastases. RESULTS: Fifteen patients (6 women; Mage = 57 years; range 29-91 years) were enrolled into the study. Forty-six distinct lesions were identified in these 15 patients on (124)I PET/CT images, with a sensitivity of 92.5%. In addition, (124)I identified 22.5% more foci of RAI-avid lesions compared with the planar (131)I post-treatment scans. This study demonstrates different kinetic profiles for normal thyroid remnants (peaked at 24 h with mono-exponential clearance), salivary glands (peaked at 4 h with bi-exponential clearance), and metastatic lesions (protracted retention), as well as individual variations in functional volumes and thus cumulated activities. CONCLUSIONS: (124)I PET/CT is a valuable clinical imaging tool/agent, both in determining the extent of disease in the setting of metastatic DTC and in the functional volumetric and kinetic evaluation of target lesions.
BACKGROUND: Although radioactive iodine (RAI) imaging/therapy is one of the earliest applications of theranostics, there remain a number of unresolved clinical questions as to the optimization of diagnostic techniques/protocols and improvements in patient-specific treatment planning strategies. The objectives of this study were to determine the imaging characteristics and clinical feasibility of (124)I positron emission tomography/computed tomography (PET/CT) for the determination of extent of disease and evaluation of RAI kinetics in its physiologic and neoplastic distribution in patients with differentiated thyroid cancer (DTC). METHODS: The study was designed as a prospective phase II diagnostic trial of patients with confirmed DTC. Following adequate preparation, patients received 2 mCi (124)I in liquid form and sequential whole-body PET/CT imaging was performed at five time points (2-4 h, 24 ± 6 h, 48 ± 6 h, 72 ± 6 h, and 96 ± 6 h post-administration). All patients who had (124)I imaging subsequently underwent RAI treatment with (131)I, with administered activities ranging from 100 to 300 mCi. Post-treatment scans were obtained 5-7 days after RAI treatment. A by-patient and by-lesion analysis of the (124)I images was performed and compared with the post-treatment (131)I scans as well as F-18 FDG PET/CT images. Quantitative image analysis was also performed to determine the total functional volume (mL), activity per functional volume (μCi/mL), and cumulated activity (μCi/h) for remnants, salivary glands, and nodal metastases. RESULTS: Fifteen patients (6 women; Mage = 57 years; range 29-91 years) were enrolled into the study. Forty-six distinct lesions were identified in these 15 patients on (124)I PET/CT images, with a sensitivity of 92.5%. In addition, (124)I identified 22.5% more foci of RAI-avid lesions compared with the planar (131)I post-treatment scans. This study demonstrates different kinetic profiles for normal thyroid remnants (peaked at 24 h with mono-exponential clearance), salivary glands (peaked at 4 h with bi-exponential clearance), and metastatic lesions (protracted retention), as well as individual variations in functional volumes and thus cumulated activities. CONCLUSIONS: (124)I PET/CT is a valuable clinical imaging tool/agent, both in determining the extent of disease in the setting of metastatic DTC and in the functional volumetric and kinetic evaluation of target lesions.
Authors: Jim O'Doherty; Maite Jauregui-Osoro; Teresa Brothwood; Teresa Szyszko; Paul K Marsden; Michael J O'Doherty; Gary J R Cook; Philip J Blower; Val Lewington Journal: J Nucl Med Date: 2017-04-06 Impact factor: 10.057
Authors: Gokce Engudar; Henrik Schaarup-Jensen; Frederikke P Fliedner; Anders E Hansen; Paul Kempen; Rasmus I Jølck; Andreas Kjæer; Thomas L Andresen; Mads H Clausen; Andreas I Jensen; Jonas R Henriksen Journal: Theranostics Date: 2018-11-12 Impact factor: 11.556