The Journal of Nuclear Medicine最新文献

{"title":"First-Line [177Lu]Lu-PSMA-617 Therapy Without ADT, Chemotherapy, or Local Therapy for Metastatic Hormone-Sensitive Prostate Cancer","authors":"Vinay K. Giri, Gerald M. Kolodny, Marc B. Garnick","doi":"10.2967/jnumed.125.270704","DOIUrl":"https://doi.org/10.2967/jnumed.125.270704","url":null,"abstract":"<sec><st>Visual Abstract</st><p><fig loc=\"float\"><link locator=\"jnumed.125.270704absf1\"></fig></p></sec>","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"68 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145141543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PET Imaging of the Human Brain with Microvolumetric Spatial Resolution","authors":"Vincent Doyon, Otman Sarrhini, Francis Loignon-Houle, Maxime Toussaint, Étienne Auger, Christian Thibaudeau, Etienne Croteau, Éric Lavallée, Jean-François Beaudoin, Jean-Daniel Leroux, Éric Turcotte, Roger Lecomte","doi":"10.2967/jnumed.124.268809","DOIUrl":"https://doi.org/10.2967/jnumed.124.268809","url":null,"abstract":"<p>PET is the modality of choice for studying the biochemistry and physiology of the human brain in vivo, although its low spatial resolution, attributable to inherent physical and technical constraints, has limited its ability to resolve small cerebral structures. Here, we report PET images of the human brain obtained at a volumetric resolution of nearly 2 µL. <strong>Methods:</strong> A dedicated ultra-high-resolution (UHR) PET scanner featuring 1.2-mm true pixelated detectors was developed to achieve microvolumetric spatial resolution. A partially assembled UHR PET scanner with an axial field of view of 143 mm was used to obtain ¹⁸F-FDG PET images of the human brain. Patients who had a clinical PET/CT scan subsequently underwent UHR PET on completion of their medical examination. UHR PET images were reconstructed using a 3-dimensional ordered-subset expectation maximization iterative algorithm with analytic coincidence function modeling. Reconstructed images were normalized to the Montreal Neurological Institute 152 brain template and analyzed using atlases for region identification. Relative SUVs to the cerebellum were extracted for selected small brain structures. <strong>Results:</strong> All major brain regions were easily identifiable in UHR PET images, including details of the primary motor and somatosensory cortices, caudate nucleus, putamen, thalamus, inferior colliculi, and dentate nuclei. Notably, regions rarely seen so distinctly with ¹⁸F-FDG PET, such as the subthalamic areas and brainstem nuclei, were successfully resolved, suggesting that UHR PET has the potential to provide enhanced quantification of these tiny cerebral structures. This was further confirmed by higher SUV ratios in the UHR PET images compared with the PET/CT images. The UHR PET image of 1 patient revealed hypermetabolic foci in the cerebellum that were not discernible on the PET/CT and MR images. <strong>Conclusion:</strong> UHR PET images of the human brain at nearly 2-µL volumetric spatial resolution were obtained. Previously indistinguishable, small, highly relevant regions of the brain were resolved, paving the way for more accurate and detailed studies with the potential for greater insight in neuropsychiatry, neurooncology, and neurodegenerative diseases.</p>","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145141514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biodistribution and Radiation Dosimetry of [68Ga]Ga-RAYZ-8009, a Glypican 3–Targeting Compound for Imaging of Hepatocellular Carcinoma","authors":"Oliver Viering, Julia Brosch-Lenz, Ralph A. Bundschuh, Helen Scholtissek, Johanna S. Enke, Adriana Amerein, Georgine Wienand, Alexander Dierks, Malte Kircher, Marianne Patt, Christian H. Pfob, Constantin Lapa","doi":"10.2967/jnumed.125.270267","DOIUrl":"https://doi.org/10.2967/jnumed.125.270267","url":null,"abstract":"<p>Glypican 3 is highly expressed in hepatocellular carcinoma (HCC), rendering it a promising target for disease imaging. [⁶⁸Ga]Ga-RAYZ-8009 is a recently introduced PET tracer selective for glypican 3. To further assess the safety and suitability of this radiopharmaceutical in a clinical setting, whole-body distribution and radiation dosimetry were evaluated. <strong>Methods:</strong> Six patients with histologically confirmed HCC or clinical or imaging-based suspicion of HCC were intravenously injected with 103–167 MBq of [⁶⁸Ga]Ga-RAYZ-8009 (mean ± SD, 150 ± 22 MBq). Whole-body PET/CT scans were acquired at 10 min, 1 h, 2 h, 4 h, and 7 h after tracer injection. Time–activity curves per organ were determined, and mean organ-absorbed doses and effective doses were calculated using IDAC-Dose 2.1. <strong>Results:</strong> Injection of a standard activity of 150 MBq of [⁶⁸Ga]Ga-RAYZ-8009 resulted in a median effective dose of 3.6 mSv for the male reference phantom. The highest absorbed organ doses were observed in the kidneys (median of 0.175 mGy/MBq and 0.179 mGy/MBq for male and female reference phantom, respectively), followed by the red bone marrow (median of 0.044 mGy/MBq for male/female reference phantom) and the stomach wall (median of 0.060 and 0.062 mGy/MBq for male and female reference phantom, respectively). <strong>Conclusion:</strong> [⁶⁸Ga]Ga-RAYZ-8009 demonstrates a favorable biodistribution and dosimetry in patients with HCC.</p>","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"102 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145141486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"OpenDose3D: A Free, Open-Source Clinical Dosimetry Software for Patient-Specific Dosimetry","authors":"José-Alejandro Fragoso-Negrín, Alex Vergara-Gil, Assyifa Rahman Hakim, Deni Hardiansyah, Gerhard Glatting, Ludovic Ferrer, Nicolas Varmenot, Lore Santoro, Susana Veloza-Awad, Kevin Hébert, Emmanuel Deshayes, Manuel Bardiès","doi":"10.2967/jnumed.125.269539","DOIUrl":"https://doi.org/10.2967/jnumed.125.269539","url":null,"abstract":"<sec><st>Visual Abstract</st><p><fig loc=\"float\"><link locator=\"jnumed.125.269539absf1\"></fig></p></sec>","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"61 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145141515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diagnostic Reliability and Clinical Impact of [11C]Choline PET/CT for Detecting Hyperfunctioning Parathyroid Glands","authors":"Alexandra Lazar, Giovanni Matassa, Dema Wahid Hammami, Arturo Chiti, Riccardo Maggiore, Martina Sollini, Lidija Antunovic","doi":"10.2967/jnumed.125.270664","DOIUrl":"https://doi.org/10.2967/jnumed.125.270664","url":null,"abstract":"<p>[¹¹C]choline PET/CT could become the preferred method for detecting hyperfunctioning parathyroid glands in patients with clinical hyperparathyroidism (cHPT), given its growing accessibility and superior diagnostic performance compared with conventional imaging. This study aimed to evaluate the robustness of [¹¹C]choline PET/CT in identifying and localizing hyperfunctioning parathyroid glands in preoperative settings. <strong>Methods:</strong> This retrospective study included patients with biochemically proven cHPT who underwent [¹¹C]choline PET/CT for preoperative localization of parathyroid adenomas. Parathyroid hormone levels, calcium metabolism, and previous scintigraphy and ultrasound results were collected for each patient, along with available histopathology results. Three reviewers evaluated the presence and anatomic localization of adenomas, and interobserver agreement was assessed. The diagnostic performance of [¹¹C]choline PET/CT was assessed exclusively in patients who underwent surgical resection or fine-needle aspiration biopsy of the suspected hyperfunctioning glands, using histopathologic results as the reference standard. <strong>Results:</strong> This study included 174 patients. Moderate interobserver agreement was reached regarding examination positivity (Fleiss κ, 0.636; 95% CI, 0.633–0.638) and gland localization (Fleiss κ, 0.656; 95% CI, 0.655–0.657). In the patient-based analysis, [¹¹C]choline PET/CT had a sensitivity of 92.2% and a positive predictive value of 98.3%; in the lesion-based analysis, the sensitivity reached 88.2%, with a positive predictive value of 96.8%. The cure rate of cHPT after [¹¹C]choline PET/CT–guided surgery was 84.1% (95% CI, 73.5%–91.3%). <strong>Conclusion:</strong> Our findings support the diagnostic efficacy of [¹¹C]choline PET/CT in patients with cHPT. Although the diagnostic performance is promising, the moderate interobserver agreement, particularly related to the accuracy of localizing ectopic parathyroid glands, calls for a refinement of interpretation criteria to improve the use of this imaging technique.</p>","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145141189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thyroid Hormone Withdrawal Yields Higher 131I Absorbed Dose to Metastases Than rhTSH Stimulation in Differentiated Thyroid Cancer: Evidence from a Large 124I PET/CT Dosimetry Cohort","authors":"Ieva Čiučiulkaitė, Giulia A. Zuccotti, Cherbel Jallo, Hubertus Hautzel, Tim Brandenburg, Pedro F. Costa, Alina T. Küper, Stephan M. Himmen, Rainer Görges, Andreas Bockisch, Ken Herrmann, Walter Jentzen, David Kersting, Wolfgang P. Fendler","doi":"10.2967/jnumed.125.270391","DOIUrl":"https://doi.org/10.2967/jnumed.125.270391","url":null,"abstract":"<p>Achieving an optimal ¹³¹I absorbed dose in differentiated thyroid carcinoma lesions is crucial for the success of radioiodine therapy. Sufficient thyroid-stimulating hormone (TSH) stimulation before radioiodine therapy can be achieved with either thyroid hormone withdrawal (THW) or by injection of recombinant human TSH (rhTSH). We compared the predicted ¹³¹I lesion absorbed dose between THW and rhTSH stimulation in patients assessed by pretherapeutic ¹²⁴I PET/CT dosimetry. <strong>Methods:</strong> This retrospective study included patients with differentiated thyroid carcinoma who had undergone total thyroidectomy with or without cervical lymph node dissection and had received ¹²⁴I PET/CT lesion dosimetry. All patients underwent TSH stimulation with either rhTSH injection or THW. For lesion dosimetry, 2 ¹²⁴I PET/CT examinations were performed after ¹²⁴I administration. Using ¹²⁴I PET data, the lesion absorbed dose per unit of administered activity (LDpA) of ¹³¹I was calculated for each lesion. Patients and lesions were categorized by the TSH stimulation method used and the clinical indication for dosimetry (adjuvant, residual/recurrent, or metastatic disease). Lesions were further categorized by location (thyroid remnants, cervical lymph node metastases, or distant metastases). <strong>Results:</strong> In total, 453 dosimetry cycles and 949 lesions were analyzed in 367 patients. TSH levels were significantly higher after rhTSH stimulation in the overall patient group (<em>P</em> &lt; 0.001) and across all subgroups (<em>P</em> = 0.038 for adjuvant; <em>P</em> = 0.002 for residual/recurrent; <em>P</em> &lt; 0.001 for metastatic). Thyroglobulin levels were significantly elevated after rhTSH stimulation in both the overall patient group (<em>P</em> &lt; 0.001) and the metastatic subgroup (<em>P</em> = 0.030). LDpA values were significantly higher after THW in the overall patient group (<em>P</em> &lt; 0.001) and in the adjuvant subgroup (<em>P</em> = 0.049). LDpA values of thyroid remnants did not significantly differ between both stimulation methods. Conversely, LDpA values were significantly higher after THW in cervical lymph node (<em>P</em> = 0.005) and distant (<em>P</em> = 0.001) metastases. <strong>Conclusion:</strong> As assessed by pretherapeutic ¹²⁴I PET/CT dosimetry, absorbed doses to metastatic lesions were higher after THW compared with rhTSH, whereas absorbed doses of thyroid remnants were comparable between both stimulation methods. In this interpatient comparison, data support the use of THW in patients with an elevated risk of metastatic disease; however, a large intrapatient study is warranted for further validation.</p>","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145141540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prognostic Value of AI-Assisted Lesion Tracking on End-of-Treatment PSMA PET in mCRPC Patients Treated with 177Lu-PSMA: A Retrospective, Single-Center Study","authors":"Vishnu Murthy, Koichiro Kimura, Lela Theus, Andrew Nguyen, Ojaswita Lokre, Timothy Perk, Pan Thin, Kathleen Nguyen, Vinicius Ludwig, Lucia Chen, Andrei Gafita, Johannes Czernin, Jeremie Calais","doi":"10.2967/jnumed.125.269971","DOIUrl":"https://doi.org/10.2967/jnumed.125.269971","url":null,"abstract":"<p>This study aimed to explore the prognostic value of the artificial intelligence–assisted lesion tracking applied to prostate-specific membrane antigen (PSMA) PET in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with PSMA radiopharmaceutical therapy. <strong>Methods:</strong> TRAQinform IQ was applied to baseline and end-of-treatment ⁶⁸Ga-PSMA-11 PET scans from 20 patients with mCRPC treated with ¹⁷⁷Lu-PSMA-617. Lesion response parameters and the TRAQinform Profile score—designed for early treatment response assessment—were generated. Survival analyses were performed. <strong>Results:</strong> A higher percentage of “new” lesions was associated with a shorter overall survival (OS) (hazard ratio, 1.03; <em>P</em> = 0.002), whereas a higher percentage of “disappeared” lesions was linked to improved OS (hazard ratio, 0.98; <em>P</em> = 0.028). Patients with a TRAQinform Profile score of 2.7 or greater had a shorter OS than those with a score of less than 2.7 (10.9 mo vs. 44.3 mo; <em>P</em> = 0.027). <strong>Conclusion:</strong> Artificial intelligence–assisted lesion-tracking analysis of PSMA PET is prognostic for OS in patients with mCRPC undergoing PSMA radiopharmaceutical therapy.</p>","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145141516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Safety of the Combination of External Beam Radiotherapy with 177Lu-PSMA-617 in Patients with Metastatic Castration-Resistant Prostate Cancer","authors":"Abigail Pepin, Abigail Doucette, Neha Vapiwala, Vivek K. Narayan, Samuel U. Takvorian, Sophia R. O’Brien, David A. Mankoff, Philipose Mulugeta, Neil K. Taunk","doi":"10.2967/jnumed.125.270316","DOIUrl":"https://doi.org/10.2967/jnumed.125.270316","url":null,"abstract":"&lt;p&gt;The VISION trial of &lt;sup&gt;177&lt;/sup&gt;Lu-PSMA-617 (LuPSMA) demonstrated improved overall survival in patients with metastatic castration-resistant prostate cancer when compared with the best standard of care. The practice patterns for and safety of the combination of external beam radiotherapy (EBRT) and LuPSMA in the real-world setting are unknown. Here, we characterize the toxicities and efficacy of the combination of EBRT and LuPSMA among patients with metastatic castration-resistant prostate cancer. &lt;strong&gt;Methods:&lt;/strong&gt; The records of all patients treated with LuPSMA at an urban academic institution between 2022 and 2024 were retrospectively extracted from the electronic medical record. Patients were stratified on the basis of their receipt of EBRT. Treatment characteristics of both systemic therapy and EBRT were extracted. Provider-reported toxicities after LuPSMA and EBRT were assessed. Overall survival was assessed using Kaplan–Meier analysis. &lt;strong&gt;Results:&lt;/strong&gt; The records of 113 patients were included in the analysis, including 92 patients who received EBRT and LuPSMA and 21 patients who received LuPSMA alone. The median age was 71.5 and 75 y in the combination therapy and the monotherapy groups, respectively. All patients were heavily pretreated. There were significantly higher rates of prior taxane-based chemotherapy in the combination group compared with those who received LuPSMA alone (92.4% vs. 76.2%; &lt;em&gt;P&lt;/em&gt; = 0.045). In total, 207 EBRT courses were delivered among 92 patients. Of these courses, 164 (79.2%) were administered before the start of LuPSMA and 15 (7.2%) occurred between cycles of LuPSMA. Thirty-six patients (39.1%) received periconcurrent LuPSMA (i.e., within 3 mo of receiving EBRT). Most EBRT courses were palliative in intent. There were no significant differences in fatigue, dry eye, and cytopenias after administration of LuPSMA alone compared with periconcurrent LuPSMA and EBRT. There were higher rates of thrombocytopenia (any grade) in patients who received EBRT within 3 mo of LuPSMA relative to those who received EBRT more than 3 mo before LuPSMA (60.6% vs. 34.0%; &lt;em&gt;P&lt;/em&gt; = 0.03). The median follow-up was 6.8 mo, during which there were no differences in overall survival between patients treated with prior EBRT relative to those who had never received EBRT (&lt;em&gt;P&lt;/em&gt; = 0.10). There were also no differences in overall survival in patients treated with EBRT within 3 mo of LuPSMA relative to those who had never received EBRT (&lt;em&gt;P&lt;/em&gt; = 0.10). &lt;strong&gt;Conclusion:&lt;/strong&gt; Receipt of EBRT during or within 3 mo of LuPSMA was not associated with increased toxicity compared with LuPSMA alone and was not associated with receiving fewer cycles of LuPSMA. There were no differences with respect to overall survival between patients who received prior EBRT or EBRT within 3 mo and those who had never received EBRT. Treatment with EBRT in combination with LuPSMA can be incorporated as needed for primarily pall","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"102 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145141542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep Learning for Automated Measures of SUV and Molecular Tumor Volume in [68Ga]PSMA-11 or [18F]DCFPyL, [18F]FDG, and [177Lu]Lu-PSMA-617 Imaging with Global Threshold Regional Consensus Network","authors":"Price Jackson, James P. Buteau, Lachlan McIntosh, Yu Sun, Raghava Kashyap, Sebastian Casanueva, Aravind S. Ravi Kumar, Shahneen Sandhu, Arun A. Azad, Ramin Alipour, Javad Saghebi, Grace Kong, Kerry Jewell, Michal Eifer, Neeraja Bollampally, Michael S. Hofman","doi":"10.2967/jnumed.125.270077","DOIUrl":"https://doi.org/10.2967/jnumed.125.270077","url":null,"abstract":"<p>Metastatic castration-resistant prostate cancer has a high rate of mortality with a limited number of effective treatments after hormone therapy. Radiopharmaceutical therapy with [¹⁷⁷Lu]Lu-prostate-specific membrane antigen–617 (LuPSMA) is one treatment option; however, response varies and is partly predicted by PSMA expression and metabolic activity, assessed on [⁶⁸Ga]PSMA-11 or [¹⁸F]DCFPyL and [¹⁸F]FDG PET, respectively. Automated methods to measure these on PET imaging have previously yielded modest accuracy. Refining computational workflows and standardizing approaches may improve patient selection and prognostication for LuPSMA therapy. <strong>Methods:</strong> PET/CT and quantitative SPECT/CT images from an institutional cohort of patients staged for LuPSMA therapy were annotated for total disease burden. In total, 676 [⁶⁸Ga]PSMA-11 or [¹⁸F]DCFPyL PET, 390 [¹⁸F]FDG PET, and 477 LuPSMA SPECT images were used for development of automated workflow and tested on 56 cases with externally referred PET/CT staging. A segmentation framework, the Global Threshold Regional Consensus Network, was developed based on nnU-Net, with processing refinements to improve boundary definition and overall label accuracy. <strong>Results:</strong> Using the model to contour disease extent, the mean volumetric Dice similarity coefficient for [⁶⁸Ga]PSMA-11 or [¹⁸F]DCFPyL PET was 0.94, for [¹⁸F]FDG PET was 0.84, and for LuPSMA SPECT was 0.97. On external test cases, Dice accuracy was 0.95 and 0.84 on PSMA and FDG PET, respectively. The refined models yielded consistent improvements compared with nnU-Net, with an increase of 3%–5% in Dice accuracy and 10%–17% in surface agreement. Quantitative biomarkers were compared with a human-defined ground truth using the Pearson coefficient, with scores for [⁶⁸Ga]PSMA-11 or [¹⁸F]DCFPyL, [¹⁸F]FDG, and LuPSMA, respectively, of 0.98, 0.94, and 0.99 for disease volume; 0.98, 0.88, and 0.99 for SUV_mean; 0.96, 0.91, and 0.99 for SUV_max; and 0.97, 0.96, and 0.99 for volume intensity product. <strong>Conclusion:</strong> Delineation of disease extent and tracer avidity can be performed with a high degree of accuracy using automated deep learning methods. By incorporating threshold-based postprocessing, the tools can closely match the output of manual workflows. Pretrained models and scripts to adapt to institutional data are provided for open use.</p>","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145083696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantification of 18F-FDG Delivery Rate for Liver Inflammation Using Shortened Dynamic PET Imaging Protocols","authors":"Xiaoyu Duan, Souvik Sarkar, Victoria Lyo, Sean Romeo, Benjamin A. Spencer, Karen E. Matsukuma, Valentina Medici, Michael T. Corwin, Ramsey D. Badawi, Guobao Wang","doi":"10.2967/jnumed.124.269434","DOIUrl":"https://doi.org/10.2967/jnumed.124.269434","url":null,"abstract":"&lt;p&gt;Liver inflammation is a diagnostic hallmark of metabolic dysfunction-associated steatohepatitis (MASH), a severe form of chronic metabolic dysfunction–associated steatotic liver disease. &lt;sup&gt;18&lt;/sup&gt;F-FDG delivery rate (&lt;em&gt;K&lt;/em&gt;&lt;sub&gt;1&lt;/sub&gt;) in the liver, measured by dynamic PET with tracer kinetic modeling, has the potential to assess liver inflammation and diagnose MASH noninvasively. However, a 1-h scan protocol is typically used to generate the liver &lt;span&gt;&lt;span&gt;&lt;img alt=\"Embedded Image\" data-src=\"https://jnm.snmjournals.org/sites/default/files/highwire/jnumed/early/2025/09/18/jnumed.124.269434/embed/mml-math-1.gif\" src=\"data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\"/&gt;&lt;noscript&gt;&lt;img alt=\"Embedded Image\" src=\"https://jnm.snmjournals.org/sites/default/files/highwire/jnumed/early/2025/09/18/jnumed.124.269434/embed/mml-math-1.gif\"/&gt;&lt;/noscript&gt;&lt;/span&gt;&lt;/span&gt;, which is less practical for clinical use. In this study, we aimed to investigate shortened scan protocols for quantification of liver &lt;sup&gt;18&lt;/sup&gt;F-FDG &lt;span&gt;&lt;span&gt;&lt;img alt=\"Embedded Image\" data-src=\"https://jnm.snmjournals.org/sites/default/files/highwire/jnumed/early/2025/09/18/jnumed.124.269434/embed/mml-math-2.gif\" src=\"data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\"/&gt;&lt;noscript&gt;&lt;img alt=\"Embedded Image\" src=\"https://jnm.snmjournals.org/sites/default/files/highwire/jnumed/early/2025/09/18/jnumed.124.269434/embed/mml-math-2.gif\"/&gt;&lt;/noscript&gt;&lt;/span&gt;&lt;/span&gt; in patients with MASH. &lt;strong&gt;Methods:&lt;/strong&gt; Eighty-two subjects, including 68 patients with metabolic dysfunction–associated steatotic liver disease and 14 healthy volunteers, were scanned on either a short–axial-field-of-view PET/CT scanner or a total-body PET/CT system following a full 1-h dynamic scan protocol. Two shortened scan protocols were proposed with appropriate tracer kinetic models: a 15-min dynamic scan with a 2-tissue reversible model and a 10-min dynamic scan with a 2-tissue irreversible model. Liver &lt;span&gt;&lt;span&gt;&lt;img alt=\"Embedded Image\" data-src=\"https://jnm.snmjournals.org/sites/default/files/highwire/jnumed/early/2025/09/18/jnumed.124.269434/embed/mml-math-3.gif\" src=\"data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7\"/&gt;&lt;noscript&gt;&lt;img alt=\"Embedded Image\" src=\"https://jnm.snmjournals.org/sites/default/files/highwire/jnumed/early/2025/09/18/jnumed.124.269434/embed/mml-math-3.gif\"/&gt;&lt;/noscript&gt;&lt;/span&gt;&lt;/span&gt; values generated from the shortened scan protocols were compared with those generated from the full 1-h scan and used to assess biopsy-determined liver inflammation and MASH using receiver-operating-characteristic analysis. &lt;strong&gt;Results:&lt;/strong&gt; Liver &lt;sup&gt;18&lt;/sup&gt;F-FDG &lt;span&gt;&lt;span&gt;&lt;img alt=\"Embedded Image\" data-src=\"https://jnm.snmjournals.org/sites/default/files/highwire/jnumed/early/2025/09/18/jnumed.124.269434/embed/mml-math-4.gif\" src=\"data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAI","PeriodicalId":22820,"journal":{"name":"The Journal of Nuclear Medicine","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145083694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}