EJNMMI Research最新文献

{"title":"Biphasic contrast-enhanced [¹⁸F]PSMA-1007 PET/CT imaging to improve the detection of local relapse of prostate cancer.","authors":"Eduards Mamlins, Emil Novruzov, Tadashi Watabe, Yuriko Mori, Mardjan Dabir, Katalin Mattes-György, Christina Antke, Jan Henke, Matthias Boschheidgen, Julian Kirchner, Danny Jazmati, Jan Hausmann, Jan P Radtke, Günter Niegisch, Jens Cardinale, Juliane Hörner-Rieber, Peter Albers, Gerald Antoch, Frederik L Giesel, Lars Schimmöller","doi":"10.1186/s13550-025-01252-4","DOIUrl":"10.1186/s13550-025-01252-4","url":null,"abstract":"<p><strong>Background: </strong>The implementation of PSMA imaging in prostate cancer (PC) management has significantly improved the medical care of patients owing to its clinical impact, particularly with respect to biochemical recurrence. However, there is still an unmet clinical need regarding the correct discrimination of equivocal, centrally located, focal [¹⁸F]PSMA-1007 uptake without any CT-morphological findings in the postsurgical prostate bed. The aim of this monocentric, retrospective study was to investigate the efficacy of a biphasic, contrast-enhanced [¹⁸F]PSMA-1007 acquisition protocol.</p><p><strong>Results: </strong>This study investigated a total of 24 biologically male patients with BCR, with a mean PSA level of 0.96 ng/ml at the time of recurrence. The presence of local relapse was regarded as consistent by biphasic, contrast-enhanced [¹⁸F]PSMA-1007 PET/CT scans, of which 22 cases were finally validated through the composite reference standard after a 2-years follow-up. The acquisition of whole-body, contrast-enhanced PET/CT imaging data was performed after a mean of 105 (± 19) minutes, whereas late-phase PET/CT imaging of the pelvis with low-dose CT was conducted after 140 min (± 10) on average following the intravenous application of [¹⁸F]PSMA-1007 (injected mean activity of 240 MBq (± 29)). The median SUV_max and SUV_mean values of local relapse increased by 26% and 5%, respectively, in late-phase images. Moreover, median TBR with respect to the obturator internus muscle seemed to benefit the most from late-phase imaging, with an increase of 185%. The dynamics of the SUV metrics and TBR in lesions were statistically significant (P value < 0.001-0.019). Moreover, the retrospective reading of delayed [¹⁸F]PSMA-1007 PET/CT imaging provided an upgrade of the reporting for suspected local PC relapse from a previous PSMA-RADS 3A to a later PSMA-RADS 5 in seven patients (29%), unless the impact of contrast agent in the urethra would also be considered equally important. For the remaining patients, the qualitative evaluation of contrast agent displacement in the urethra was necessary for a final clinical decision that provided the upgrading of the reporting to PSMA RADS 5 for an additional nine patients (38%).</p><p><strong>Conclusions: </strong>Given the aforementioned, highly specific unmet clinical need for a relatively small ratio of patients with prostate cancer undergoing PSMA imaging, our proposed acquisition protocol mandates a well-balanced preselection of patients. Under this premise, the study results demonstrated that the optimized acquisition protocol with biphasic contrast-enhanced [¹⁸F]PSMA-1007 PET/CT imaging improved the diagnostic performance for the detection of local PC recurrence in 67% of preselected patients.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"61"},"PeriodicalIF":3.1,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12125407/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144186807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metabolic parameters on baseline and early [¹⁸F]FDG PET/CT as a predictive biomarker for resistance to BRAF/MEK inhibition in advanced cutaneous BRAFV600-mutated melanoma.","authors":"Bernies van der Hiel, Berlinda J de Wit-van der Veen, Alfons J M van den Eertwegh, Wouter V Vogel, Marcel P M Stokkel, Marta Lopez-Yurda, Ronald Boellaard, Ellen W Kapiteijn, Geke A P Hospers, Maureen J B Aarts, Filip Y F L de Vos, Marye J Boers-Sonderen, Astrid A M van der Veldt, Jan Willem B de Groot, John B A G Haanen","doi":"10.1186/s13550-025-01259-x","DOIUrl":"10.1186/s13550-025-01259-x","url":null,"abstract":"<p><strong>Background: </strong>[¹⁸F]FDG PET/CT plays a crucial role in evaluating cancer patients and assessing treatment response, including in BRAF-mutated melanoma. Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) have emerged as promising alternatives to standardized uptake value (SUV)-based measures for tumor assessment. This study evaluates the predictive value of SUVpeak, MTV, and TLG in predicting progression-free survival (PFS) in advanced BRAF-mutated melanoma treated with BRAF/MEK inhibitors.</p><p><strong>Results: </strong>Seventy-five patients with metastatic melanoma were enrolled in a multi-center trial and treated with vemurafenib/cobimetinib. [¹⁸F]FDG-PET/CT scans were performed at baseline, week-2, and week-7. Imaging analysis included SUVpeak, MTV, and TLG of summed metastases, as well as percentage changes over time (∆). Baseline median PET-parameters were SUVpeak 12.59 (range 3.13-50.59), MTV 159mL (range 0-1897 mL), and TLG 1013 (range 1-13162). Baseline MTV was the strongest predictor (AUC_{T=6 months}=0.714), while early changes in MTV, TLG, and especially week-7 ΔSUVpeak% showed similar or improved performance (P = 0.017 vs. baseline SUVpeak). Patients with TLG below the median had significantly prolonged PFS (15.4 vs. 8.5 months, P = 0.024). MTV above optimal cutoff (45.3 mL) was associated with an increased risk of progression/death, even after adjusting for LDH, ECOG status, and metastatic sites (HR = 2.97, 95% CI 1.17-7.52, P = 0.022). At week-2, ∆SUVpeak% was not predictive in a multivariable analysis, but became predictive at week-7 (median ∆SUVpeak%: 64), with a more than three-fold hazard of progression for patients with ∆SUVpeak% below 64% (P = 0.0014); PFS was 5.0 months (95% CI: 4.3-NA) for patients below the median versus 14.7 months (95% CI: 9.2-20.2) for those above or with non-quantifiable scans (P = 0.0002). Median ∆MTV was 95.5% at week-2 and 97.6% at week-7, with significant PFS differences at both time points (week-2: P = 0.020, week-7: P < 0.001). As expected, TLG mirrored MTV. Patients with MTV increases at week-7 after an initial response at week-2 had a median PFS of 5.3 vs. 12.6 months for those with stable or declining MTV (P = 0.0023). Intra-patient metabolic heterogeneity was also associated with outcome, with early reductions in SUVpeak variation between lesions correlating with better PFS.</p><p><strong>Conclusion: </strong>This study supports the use of MTV and TLG as robust predictive markers for PFS in advanced melanoma treated with BRAF/MEK-inhibitors. Monitoring early PET parameters changes can provide valuable insights into therapeutic response and disease progression.</p><p><strong>Trial registration: </strong>Clinicaltrials.gov identifier: NCT02414750. Registered 10 April 2015, retrospectively registered.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"60"},"PeriodicalIF":3.1,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12119442/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144157370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiation protection considerations with [⁸⁹Zr]Zr-girentuximab PET and surgery.","authors":"Adnan Chowdhury, Clément Morgat, Clement Bailly, John Sunderland, Stephen A Graves, Andrew M Scott, Sean Baker, Beverley F Holman","doi":"10.1186/s13550-025-01247-1","DOIUrl":"10.1186/s13550-025-01247-1","url":null,"abstract":"<p><strong>Background: </strong>⁸⁹Zr is emerging as a popular positron-emitting radionuclide for imaging; however, its 909 keV gamma emission presents shielding challenges, and radiation exposure safety guidelines for healthcare professionals working with the radionuclide have not been well-established. To guide assessment of the radiation risk and necessary safety guidelines, we present laboratory dose rate measurements of ⁸⁹Zr syringes and vials, and dose rates measurements made during the ZIRCON clinical trial ([⁸⁹Zr]Zr-girentuximab) to evaluate healthcare provider exposure during administration, imaging, and surgical procedures.</p><p><strong>Results: </strong>The maximum dose rate from a vial with no shielding was 0.334 µSv/h/MBq, and the minimum dose rate with 66 mm lead shielding was 0.004 µSv/h/MBq. The controlled spill measured 0.52 µSv/h/MBq. Dose rates 1 m from patients who received [⁸⁹Zr]Zr-girentuximab had an average of 3.90 µSv/h at imaging. During surgery, waste measured below background levels, and a bed assistant 0.8 m from the patient received a 5 µSv/h whole-body dose rate. The excised kidney measured 6 µSv/h at 5 cm.</p><p><strong>Conclusions: </strong>Our results demonstrate low radiation exposure levels associated with ⁸⁹Zr handling and exposure to the patient. With potential integration of ⁸⁹Zr into clinical practice, appropriate radiation safety guidelines are needed. Dose rate measurements can help guide development of best practices and site-specific protocols.</p><p><strong>Clinical trial number: </strong>not applicable for this study; ZIRCON trial number NCT03849118, registered on 19 February 2019.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"59"},"PeriodicalIF":3.1,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12102418/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144127023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-invasive arterial input function estimation using an MRA atlas and machine learning.","authors":"Rajat Vashistha, Hamed Moradi, Amanda Hammond, Kieran O'Brien, Axel Rominger, Hasan Sari, Kuangyu Shi, Viktor Vegh, David Reutens","doi":"10.1186/s13550-025-01253-3","DOIUrl":"10.1186/s13550-025-01253-3","url":null,"abstract":"<p><strong>Background: </strong>Quantifying biological parameters of interest through dynamic positron emission tomography (PET) requires an arterial input function (AIF) conventionally obtained from arterial blood samples. The AIF can also be non-invasively estimated from blood pools in PET images, often identified using co-registered MRI images. Deploying methods without blood sampling or the use of MRI generally requires total body PET systems with a long axial field-of-view (LAFOV) that includes a large cardiovascular blood pool. However, the number of such systems in clinical use is currently much smaller than that of short axial field-of-view (SAFOV) scanners. We propose a data-driven approach for AIF estimation for SAFOV PET scanners, which is non-invasive and does not require MRI or blood sampling using brain PET scans. The proposed method was validated using dynamic ¹⁸F-fluorodeoxyglucose [¹⁸F]FDG total body PET data from 10 subjects. A variational inference-based machine learning approach was employed to correct for peak activity. The prior was estimated using a probabilistic vascular MRI atlas, registered to each subject's PET image to identify cerebral arteries in the brain.</p><p><strong>Results: </strong>The estimated AIF using brain PET images (IDIF-Brain) was compared to that obtained using data from the descending aorta of the heart (IDIF-DA). Kinetic rate constants (K₁, k₂, k₃) and net radiotracer influx (K_i) for both cases were computed and compared. Qualitatively, the shape of IDIF-Brain matched that of IDIF-DA, capturing information on both the peak and tail of the AIF. The area under the curve (AUC) of IDIF-Brain and IDIF-DA were similar, with an average relative error of 9%. The mean Pearson correlations between kinetic parameters (K₁, k₂, k₃) estimated with IDIF-DA and IDIF-Brain for each voxel were between 0.92 and 0.99 in all subjects, and for K_i, it was above 0.97.</p><p><strong>Conclusion: </strong>This study introduces a new approach for AIF estimation in dynamic PET using brain PET images, a probabilistic vascular atlas, and machine learning techniques. The findings demonstrate the feasibility of non-invasive and subject-specific AIF estimation for SAFOV scanners.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"58"},"PeriodicalIF":3.1,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12102434/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144127022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiation dosimetry of [¹¹C]TZ1964B as determined by whole-body PET imaging of nonhuman primates.","authors":"Baijayanta Maiti, Noah L Goldman, Mahdjoub Hamdi, Jason Lenox-Krug, Morvarid Karimi, Stephen M Moerlein, Richard Laforest, Tianyu Huang, Zhude Tu, Joel S Perlmutter, Scott A Norris","doi":"10.1186/s13550-025-01221-x","DOIUrl":"https://doi.org/10.1186/s13550-025-01221-x","url":null,"abstract":"<p><strong>Background: </strong>Phosphodiesterase 10A (PDE10A) is a postsynaptic, membrane bound cyclic nucleotide phosphodiesterase that is highly enriched in the striatal medium spiny neurons and regulates dopaminergic neurotransmission. The objective of this study is to determine the absorbed radiation dosimetry of a novel radiotracer for PDE10A: 3-(Methoxy-¹¹C)-2-((4-(1-methyl-4-(pyridine-4yl)-1H-pyrazol-3-yl)phenoxy)methyl)quinolone ([¹¹C]TZ1964B) based on whole body PET imaging in nonhuman primates, a critical step before translating this radiotracer to imaging studies in humans. [¹¹C]TZ1964B may contribute to the clinical investigation of multiple neuropsychiatric conditions including Parkinson disease, Huntington disease and schizophrenia. For absorbed radiation measures, two males and one female cynomolgus monkeys (Macaca fascicularis) had intravenous injections of 302.3-384.4 MBq of [¹¹C]TZ1964B followed by sequential whole body PET imaging in a MicroPET-Focus220 scanner. Volumes of interest (VOIs) that either encompassed the entire organ or sampled regions of highest activity within larger organs were defined. Time-activity curves were derived from the PET data for each VOI, and analytical integration of its multi-exponential fit yielded the organ time-integrated activity. We generated human radiation dose estimates based on the scaled organ residence using OLINDA/EXM2.2.</p><p><strong>Results: </strong>Highest retention was observed in the liver with total time-integrated activity of ~ 0.23 h. Absorbed organ dosimetry was highest in the liver (53.3 μGy/MBq), making it the critical organ. Gallbladder (35.9 μGy/MBq) and spleen (35.4 μGy/MBq) were the next highest organs for absorbed radiation dose. Effective doses were estimated to be 5.02 and 5.84 μSv/MBq for males and females, respectively.</p><p><strong>Conclusions: </strong>This nonhuman primate dosimetry study suggests intravenous doses up to 938 MBq of [¹¹C]TZ1964B can be safely administered to human subjects for PET measurements of PDE10A activity. The tracer kinetic data is consistent with a hepatobiliary clearance pathway for the radiotracer.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"57"},"PeriodicalIF":3.1,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12078849/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144076814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Test-retest repeatability of quantitative organ and tissue uptake using 20-minute dynamic multiparametric whole-body [¹⁸F]FDG PET/CT in patients with type 2 diabetes.","authors":"Jonathan M Baier, Kristian L Funck, Anna Dons-Jensen, Ole L Munk, Lars P Tolbod, Esben Laugesen, Per L Poulsen, Lars C Gormsen, André H Dias","doi":"10.1186/s13550-025-01249-z","DOIUrl":"10.1186/s13550-025-01249-z","url":null,"abstract":"<p><strong>Background: </strong>Recently developed dynamic whole-body PET/CT (D-WB PET/CT) protocols allow for measurements of potentially more precise metabolic parameters than the commonly used semiquantitative SUV. Most notable is the metabolic rate of FDG uptake (MR_FDG), which reflects quantitative glucose uptake into tissues and organs. However, data on the reproducibility of MR_FDG measurements are scarce, particularly in patients with perturbed glucose homeostasis such as type 2 diabetes. We therefore aimed to evaluate the test-retest repeatability of both MR_FDG and SUV in these patients.</p><p><strong>Results: </strong>Fifteen participants (mean age 71 ± 7 years; 2 females) with type 2 diabetes underwent a short 20-minute [¹⁸F]FDG D-WB PET/CT after 6 h fasting on two consecutive days. Both SUV and MR_FDG images were reconstructed from D-WB PET/CT data obtained 60-80 min post-injection of [¹⁸F]FDG. MR_FDG and SUV data were measured in organs and tissues, and repeatability was assessed with Bland-Altman analysis, intraclass correlation coefficients (ICC), repeatability coefficients (RPC) and coefficients of variation (wCV). There was high repeatability of both SUV_mean and MR_FDG-mean in all measured organs (ICC range: 0.65-0.95 for SUV_mean and 0.66-0.94 for MR_FDG-mean). SUV_mean generally demonstrated higher reliability (ICC) and lower variability (%RPC and %wCV) when compared to MR_FDG-mean. However, MR_FDG test-retest variation was < 19% in most analysed tissues, demonstrating that MR_FDG may be used as a precise marker of treatment response.</p><p><strong>Conclusion: </strong>This study demonstrates that MR_FDG calculated from D-WB PET/CT exhibit high repeatability, comparable to SUVs across most organs in patients with type 2 diabetes.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"56"},"PeriodicalIF":3.1,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12069784/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143983483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep learning for Parkinson's disease classification using multimodal and multi-sequences PET/MR images.","authors":"Yan Chang, Jiajin Liu, Shuwei Sun, Tong Chen, Ruimin Wang","doi":"10.1186/s13550-025-01245-3","DOIUrl":"https://doi.org/10.1186/s13550-025-01245-3","url":null,"abstract":"<p><strong>Background: </strong>We aimed to use deep learning (DL) techniques to accurately differentiate Parkinson's disease (PD) from multiple system atrophy (MSA), which share similar clinical presentations. In this retrospective analysis, 206 patients who underwent PET/MR imaging at the Chinese PLA General Hospital were included, having been clinically diagnosed with either PD or MSA; an additional 38 healthy volunteers served as normal controls (NC). All subjects were randomly assigned to the training and test sets at a ratio of 7:3. The input to the model consists of 10 two-dimensional (2D) slices in axial, coronal, and sagittal planes from multi-modal images. A modified Residual Block Network with 18 layers (ResNet18) was trained with different modal images, to classify PD, MSA, and NC. A four-fold cross-validation method was applied in the training set. Performance evaluations included accuracy, precision, recall, F1 score, Receiver operating characteristic (ROC), and area under the ROC curve (AUC).</p><p><strong>Results: </strong>Six single-modal models and seven multi-modal models were trained and tested. The PET models outperformed MRI models. The ¹¹C-methyl-N-2β-carbomethoxy-3β-(4-fluorophenyl)-tropanel (¹¹C-CFT) -Apparent Diffusion Coefficient (ADC) model showed the best classification, which resulted in 0.97 accuracy, 0.93 precision, 0.95 recall, 0.92 F1, and 0.96 AUC. In the test set, the accuracy, precision, recall, and F1 score of the CFT-ADC model were 0.70, 0.73, 0.93, and 0.82, respectively.</p><p><strong>Conclusions: </strong>The proposed DL method shows potential as a high-performance assisting tool for the accurate diagnosis of PD and MSA. A multi-modal and multi-sequence model could further enhance the ability to classify PD.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"55"},"PeriodicalIF":3.1,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12064532/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143978613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PSMA-expressing, fluciclovine-negative vertebral hemangioma.","authors":"Azadeh Eslambolchi, Amin Haghighat Jahromi","doi":"10.1186/s13550-025-01248-0","DOIUrl":"https://doi.org/10.1186/s13550-025-01248-0","url":null,"abstract":"<p><strong>Background: </strong>False-positive findings in Prostate-Specific Membrane Antigen Positron Emission Tomography-Computed Tomography (PSMA PET-CT) can complicate accurate staging of prostate cancer, especially in cases such as vertebral hemangiomas, a benign lesion of the spinal column. These ambiguities may result in unnecessary biopsies in patients with prostate cancer when PSMA PET findings are inconclusive.</p><p><strong>Case presentation: </strong>We present the case of a 68-year-old male with prostate cancer who had a PSMA-expressing, fluciclovine-negative vertebral hemangioma.</p><p><strong>Conclusion: </strong>This case highlights the role of fluciclovine PET-CT in distinguishing benign vertebral hemangiomas from prostate cancer metastases, improving diagnostic accuracy specifically in positive cases of PSMA PET-CT.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"54"},"PeriodicalIF":3.1,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12064478/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143973180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative 177Lu-DOTATATE SPECT/CT is predictive of 6-month PRRT morphological response in midgut neuroendocrine tumors: a pilot study.","authors":"Iness Megherbi, Christopher Hoog, Marine Perrier, Hedia Brixi, Guillaume Cadiot, Christine Hoeffel-Fornes, David Morland","doi":"10.1186/s13550-025-01250-6","DOIUrl":"https://doi.org/10.1186/s13550-025-01250-6","url":null,"abstract":"<p><strong>Background: </strong>peptide receptor radionuclide therapy with 177Lu-DOTATATE has become an established second-line treatment for patients with advanced small intestine neuroendocrine tumors (siNET). Treatment efficacy is assessed several months after the end of treatment and is based on RECIST criteria. Post-therapy scintigraphy (PTS) can be performed after each cycle, but its value in early response assessment is debated particularly given the lack of quantification available in clinical routine. New quantification modules are now available, enabling automatic SUV calculation. The main goal of this study is to assess the value of the evolution of SUV between the first (C1) and the second (C2) cycle on quantitative PTS in predicting response to treatment. All patients with siNET referred to our center for treatment with 177Lu-DOTATATE were included. The SUVmax of the lesion with the greatest uptake was measured on PTS SPECT/CT at C1 and C2. ∆SUVmax was calculated. Linear regression between ∆SUVmax and 6-month RECIST percentage was used. Relative changes in tumor metabolic volume (MTV) were also studied along with clinical parameters.</p><p><strong>Results: </strong>twelve consecutive patients with progressive metastatic siNET were included. One patient showed partial response at 6 months, the other were considered as stable disease. Linear regression showed that 6-month RECIST percentage and ∆SUVmax were strongly correlated with the following regression formula: 6-month RECIST = -0.05 + 0.36 x ∆SUVmax (p < 0.001). ∆MTV was not predictive of response.</p><p><strong>Conclusion: </strong>we report a significant link between PTS ∆SUVmax and 6-month RECIST percentage in patients with siNET. Quantitative imaging would thus enable the prediction of 6-month response of 177Lu-DOTATATE as early as C2. These results need to be confirmed on a larger population.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"53"},"PeriodicalIF":3.1,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12055673/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144062863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A heterodimeric radioligand labeled with gallium-68 targeting fibroblast activation protein.","authors":"Chengde Xie, Lei Peng, Hui Nie, Tianhong Yang, Renbo Wu, Dake Zhang, Fuhua Wen, Junyu Chen, Lingyu Xue, Xiangsong Zhang, Zhihao Zha, Jianjun Wang","doi":"10.1186/s13550-025-01230-w","DOIUrl":"https://doi.org/10.1186/s13550-025-01230-w","url":null,"abstract":"<p><strong>Background: </strong>Fibroblast activation protein (FAP) targeting radiotracers have emerged as promising agents for cancer imaging and therapy. Recent advancements have focused on optimizing these agents for better tumor targeting and enhanced theranostic efficacy. In this study, we introduced a novel heterodimeric radioligand labeled with gallium-68, which targets FAP. We aimed to evaluate its in vitro and in vivo performance, comparing its efficacy with monomeric FAPI derivatives.</p><p><strong>Results: </strong>The heterodimeric ligand BiFAPI was synthesized by conjugating a cyclic peptide with a quinoline-based motif via a DOTA chelator. [⁶⁸ Ga]Ga-BiFAPI demonstrated high radiochemical purity (> 95%) and exceptional stability in physiological conditions, as well as in both PBS and serum. In vitro studies revealed that the binding affinity of BiFAPI was comparable to that of FAP2286 and FAPI-04. Notably, [⁶⁸ Ga]Ga-BiFAPI exhibited superior cellular uptake, with rapid internalization and slower efflux rates. Micro-PET/CT imaging in tumor-bearing mice demonstrated significantly higher tumor uptake than [⁶⁸ Ga]Ga-FAP2286 and [⁶⁸ Ga]Ga-FAPI-04. Co-injection with a FAP inhibitor reduced tumor uptake, confirming the tracer's FAP specificity. In vitro autoradiography, immunohistochemistry, and Western blotting confirmed the correlation between radioactive tracer accumulation and FAP-positive regions. Biodistribution studies revealed high tumor-to-blood ratios and rapid clearance from non-target tissues, further supporting the tracer's favorable pharmacokinetics.</p><p><strong>Conclusion: </strong>[⁶⁸ Ga]Ga-BiFAPI demonstrated superior tumor-targeting properties, higher tumor uptake, and favorable pharmacokinetics compared to [⁶⁸ Ga]Ga-FAP2286 and [⁶⁸ Ga]Ga-FAPI-04. Its promising performance in preclinical models positioned it as a potentially valuable agent for FAP-targeted PET imaging and cancer theranostics.</p>","PeriodicalId":11611,"journal":{"name":"EJNMMI Research","volume":"15 1","pages":"52"},"PeriodicalIF":3.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12044090/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143968301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}