Elin Pauwels1,2, Frederik Cleeren3, Térence Tshibangu3, Michel Koole1,2, Kim Serdons1,2, Jeroen Dekervel4, Eric Van Cutsem4, Chris Verslype4, Koen Van Laere1,2, Guy Bormans3, Christophe M Deroose5,6. 1. Nuclear Medicine, University Hospitals Leuven, Campus Gasthuisberg, Herestraat 49, BE-3000, Leuven, Belgium. 2. Nuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium. 3. Radiopharmaceutical Research, Department of Pharmacy and Pharmacology, KU Leuven, Leuven, Belgium. 4. Digestive Oncology, University Hospitals Leuven, Leuven, Belgium. 5. Nuclear Medicine, University Hospitals Leuven, Campus Gasthuisberg, Herestraat 49, BE-3000, Leuven, Belgium. christophe.deroose@uzleuven.be. 6. Nuclear Medicine and Molecular Imaging, Department of Imaging and Pathology, KU Leuven, Leuven, Belgium. christophe.deroose@uzleuven.be.
Abstract
PURPOSE: The widespread use of gallium-68-labelled somatostatin analogue (SSA) PET, the current standard for somatostatin receptor (SSTR) imaging, is limited by practical and economic challenges that could be overcome by a fluorine-18-labelled alternative, such as the recently introduced [18F]AlF-NOTA-octreotide ([18F]AlF-OC). This prospective trial aimed to evaluate safety, dosimetry, biodistribution, pharmacokinetics and lesion targeting of [18F]AlF-OC and perform the first comparison with [68Ga]Ga-DOTATATE in neuroendocrine tumour (NET) patients. METHODS: Six healthy volunteers and six NET patients with a previous clinical [68Ga]Ga-DOTATATE PET were injected with an IV bolus of 4 MBq/kg [18F]AlF-OC. Healthy volunteers underwent serial whole-body PET scans from time of tracer injection up to 90 min post-injection, with an additional PET/CT at 150 and 300 min post-injection. In patients, a 45-min dynamic PET was acquired and three whole-body PET scans at 60, 90 and 180 min post-injection. Absorbed organ doses and effective doses were calculated using OLINDA/EXM. Normal organ uptake (SUVmean) and tumour lesion uptake (SUVmax and tumour-to-background ratio (TBR)) were measured. A lesion-by-lesion analysis was performed and the detection ratio (DR), defined as the fraction of detected lesions was determined for each tracer. RESULTS: [18F]AlF-OC administration was safe and well tolerated. The highest dose was received by the spleen (0.159 ± 0.062 mGy/MBq), followed by the urinary bladder wall (0.135 ± 0.046 mGy/mBq) and the kidneys (0.070 ± 0.018 mGy/MBq), in accordance with the expected SSTR-specific uptake in the spleen and renal excretion of the tracer. The effective dose was 22.4 ± 4.4 μSv/MBq. The physiologic uptake pattern of [18F]AlF-OC was comparable to [68Ga]Ga-DOTATATE. Mean tumour SUVmax was lower for [18F]AlF-OC (12.3 ± 6.5 at 2 h post-injection vs. 18.3 ± 9.5; p = 0.03). However, no significant differences were found in TBR (9.8 ± 6.7 at 2 h post-injection vs. 13.6 ± 11.8; p = 0.35). DR was high and comparable for both tracers (86.0% for [68Ga]Ga-DOTATATE vs. 90.1% for [18F]AlF-OC at 2 h post-injection; p = 0.68). CONCLUSION: [18F]AlF-OC shows favourable kinetic and imaging characteristics in patients that warrant further head-to-head comparison to validate [18F]AlF-OC as a fluorine-18-labelled alternative for gallium-68-labelled SSA clinical PET. TRIAL REGISTRATION: Clinicaltrials.gov : NCT03883776, EudraCT: 2018-002827-40.
PURPOSE: The widespread use of gallium-68-labelled somatostatin analogue (SSA) PET, the current standard for somatostatin receptor (SSTR) imaging, is limited by practical and economic challenges that could be overcome by a fluorine-18-labelled alternative, such as the recently introduced [18F]AlF-NOTA-octreotide ([18F]AlF-OC). This prospective trial aimed to evaluate safety, dosimetry, biodistribution, pharmacokinetics and lesion targeting of [18F]AlF-OC and perform the first comparison with [68Ga]Ga-DOTATATE in neuroendocrine tumour (NET) patients. METHODS: Six healthy volunteers and six NET patients with a previous clinical [68Ga]Ga-DOTATATE PET were injected with an IV bolus of 4 MBq/kg [18F]AlF-OC. Healthy volunteers underwent serial whole-body PET scans from time of tracer injection up to 90 min post-injection, with an additional PET/CT at 150 and 300 min post-injection. In patients, a 45-min dynamic PET was acquired and three whole-body PET scans at 60, 90 and 180 min post-injection. Absorbed organ doses and effective doses were calculated using OLINDA/EXM. Normal organ uptake (SUVmean) and tumour lesion uptake (SUVmax and tumour-to-background ratio (TBR)) were measured. A lesion-by-lesion analysis was performed and the detection ratio (DR), defined as the fraction of detected lesions was determined for each tracer. RESULTS: [18F]AlF-OC administration was safe and well tolerated. The highest dose was received by the spleen (0.159 ± 0.062 mGy/MBq), followed by the urinary bladder wall (0.135 ± 0.046 mGy/mBq) and the kidneys (0.070 ± 0.018 mGy/MBq), in accordance with the expected SSTR-specific uptake in the spleen and renal excretion of the tracer. The effective dose was 22.4 ± 4.4 μSv/MBq. The physiologic uptake pattern of [18F]AlF-OC was comparable to [68Ga]Ga-DOTATATE. Mean tumour SUVmax was lower for [18F]AlF-OC (12.3 ± 6.5 at 2 h post-injection vs. 18.3 ± 9.5; p = 0.03). However, no significant differences were found in TBR (9.8 ± 6.7 at 2 h post-injection vs. 13.6 ± 11.8; p = 0.35). DR was high and comparable for both tracers (86.0% for [68Ga]Ga-DOTATATE vs. 90.1% for [18F]AlF-OC at 2 h post-injection; p = 0.68). CONCLUSION: [18F]AlF-OC shows favourable kinetic and imaging characteristics in patients that warrant further head-to-head comparison to validate [18F]AlF-OC as a fluorine-18-labelled alternative for gallium-68-labelled SSA clinical PET. TRIAL REGISTRATION: Clinicaltrials.gov : NCT03883776, EudraCT: 2018-002827-40.
Authors: Anne-Leen Deleu; Annouschka Laenen; Herbert Decaluwé; Birgit Weynand; Christophe Dooms; Walter De Wever; Sander Jentjens; Karolien Goffin; Johan Vansteenkiste; Koen Van Laere; Paul De Leyn; Kristiaan Nackaerts; Christophe M Deroose Journal: EJNMMI Res Date: 2022-05-07 Impact factor: 3.434
Authors: Leonie Beyer; Astrid Gosewisch; Simon Lindner; Friederike Völter; Lena M Mittlmeier; Reinhold Tiling; Matthias Brendel; Clemens C Cyran; Marcus Unterrainer; Johannes Rübenthaler; Christoph J Auernhammer; Christine Spitzweg; Guido Böning; F J Gildehaus; Klaus Jurkschat; Carmen Wängler; Björn Wängler; Ralf Schirrmacher; Vera Wenter; Andrei Todica; Peter Bartenstein; Harun Ilhan Journal: Eur J Nucl Med Mol Imaging Date: 2021-04-29 Impact factor: 9.236