European Journal of Nuclear Medicine and Molecular Imaging最新文献

{"title":"Nigrostriatal imaging in patients with clinically uncertain Parkinsonian syndromes: a head-to-head comparison between SPECT, PET, and MRI.","authors":"Gerda Thomsen, Kristoffer Brendstrup-Brix, Claus Svarer, Ulrich Lindberg, Lars H Pinborg, Karen Kettless, Ian Law, Steen G Hasselbalch, Bo Biering-Sørensen, Gitte M Knudsen","doi":"10.1007/s00259-026-08184-8","DOIUrl":"https://doi.org/10.1007/s00259-026-08184-8","url":null,"abstract":"<p><strong>Purpose: </strong>Neurodegenerative parkinsonism is characterized by degeneration of the dopaminergic nigrostriatal pathways and a reduction in nigral neuromelanin. Dopamine transporter (DAT) imaging assesses presynaptic striatal dopaminergic function and is typically performed with [¹²³I]FP-CIT SPECT-CT, but has recently also become available with [¹⁸F]FE-PE2I PET-CT. Magnetic resonance imaging (MRI) can explore disease-related changes by quantifying neuromelanin and iron deposition associated with the loss of nigral neurons.</p><p><strong>Methods: </strong>In this study, we conducted a head-to-head comparison of [¹²³I]FP-CIT SPECT, [¹⁸F]FE-PE2I PET, and nigral MRI in 35 patients referred for diagnostic DAT imaging. Nigral MRI was performed with neuromelanin-sensitive gradient echo magnetization-transfer contrast MRI and iron-sensitive STrategically Acquired Gradient Echo (STAGE) MRI. Patient satisfaction with SPECT and PET was recorded via questionnaires.</p><p><strong>Results: </strong>Eighteen patients were diagnosed with neurodegenerative parkinsonism with a median symptom duration of 29 months. DAT availability as measured with SPECT and PET showed complete concordance across cases, correlated strongly, and demonstrated equally excellent diagnostic performance. Patient questionnaire items were either not different between modalities or in favor of SPECT. Nigral neuromelanin content was reduced in patients with neurodegenerative parkinsonism and provided intermediate diagnostic accuracy, with indications of lower neuromelanin with disease duration. Midbrain iron content did not differ between groups and provided no diagnostic information.</p><p><strong>Conclusion: </strong>Our findings indicate that in early-stage parkinsonism, DAT neuroimaging with SPECT and PET provides comparable and superior diagnostic value relative to nigral MRI.</p>","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148988698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cerebellar cortical amyloid deposition biases ¹⁸F-Florbetapir PET quantification with whole cerebellum as reference region.","authors":"Meixi Wang, Sheng Bi, Hanxiao Xue, Le Guan, Yan Wang, Xuemei Zhang, Xiaocao Liu, Xiaoyin Xu, Chun Zhang, Zhigang Qi, Zhilian Zhao, Shaozhen Yan, Jie Lu","doi":"10.1007/s00259-026-08140-6","DOIUrl":"https://doi.org/10.1007/s00259-026-08140-6","url":null,"abstract":"<p><strong>Objective: </strong>To investigate whether cerebellar cortical amyloid-beta (Aβ) deposition biases ¹⁸F-Florbetapir Aβ PET quantification when the whole cerebellum (WC) is used as the reference region, and to identify a stable reference region for quantification. Additionally, to establish an optimal diagnostic threshold for the detection of cerebellar cortical Aβ deposition.</p><p><strong>Methods: </strong>This retrospective cohort study enrolled 359 Aβ-positive participants including 52 with and 307 without cerebellar cortical Aβ deposition. All participants underwent ¹⁸F-Florbetapir Aβ PET imaging, structural MRI, and cerebrospinal fluid biomarker analysis. Standardized uptake value ratio (SUVR) was derived from the standardized uptake value (SUV) by normalizing to WC, pons, and white matter (WM). Centiloid (CL) values were derived following standardized procedures. Bootstrap resampling was employed for group comparisons. Receiver operating characteristic (ROC) analysis was performed to determine the optimal SUVR threshold for identifying cerebellar cortical Aβ deposition, with validation conducted in an internal validation subset (n = 30). Two patients treated with lecanemab underwent longitudinal Aβ PET follow-up.</p><p><strong>Results: </strong>Individuals classified as cerebellar cortical Aβ-positive exhibited significantly lower CL values than Aβ‑negative individuals (bootstrap P < 0.001). The cerebellar cortical Aβ‑positive group showed elevated SUV_WC (bootstrap P = 0.012) and reduced SUV_cortex (bootstrap P = 0.008), whereas SUV_pons showed no significant differences between groups (bootstrap P = 0.110). SUV_WM exhibited a significant intergroup difference (bootstrap P < 0.001), while SUVR_WM showed no significant between-group difference (bootstrap P = 0.288). An optimal cerebellar SUVR_WM threshold of 0.428 yielded excellent diagnostic performance for identifying cerebellar cortical Aβ deposition, with an area under the curve (AUC) = 0.931, sensitivity 86.5%, specificity 86.3%. Substantial agreement between quantitative and visual assessment was confirmed in the validation subset (Cohen's kappa = 0.856). In the two cerebellar cortical Aβ-positive lecanemab-treated patients, CL values decreased over time, SUVR_WM showed modest alterations, while cerebellar SUVR_WM remained above the 0.428 threshold throughout follow-up.</p><p><strong>Conclusion: </strong>Cerebellar cortical Aβ deposition raises WC reference signals and interferes with CL-based ¹⁸F-Florbetapir Aβ PET quantification, which systematically underestimates true cerebral Aβ burden. The WM represents a robust reference region, and the cerebellar SUVR_WM threshold of 0.428 is reliable and practical for identifying cerebellar cortical Aβ status.</p>","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148982024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Baseline body composition and early PRRT outcome in GEP-NETs: an exploratory analysis.","authors":"Elma Dema, Christian Dascalescu, Adrien Holzgreve, Clemens C Cyran, Liam Widjaja, Franz Josef Gildehaus, Felix L Herr, Christine Spitzweg, Christoph J Auernhammer, Michael Ingrisch, Matthias Brendel, Jens Ricke, Rudolf A Werner, Sophie Carina Siegmund","doi":"10.1007/s00259-026-08182-w","DOIUrl":"https://doi.org/10.1007/s00259-026-08182-w","url":null,"abstract":"<p><strong>Purpose: </strong>Early progression after PRRT occurs in a subset of patients with somatostatin receptor-positive gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Associations between body composition and early PET-based progression after PRRT were assessed.</p><p><strong>Methods: </strong>In this retrospective analysis, 321 patients undergoing PRRT were screened. Body composition parameters were assessed on the CT component at the L3/L4 level. Myosteatosis was defined using BMI-adjusted psoas muscle attenuation cut-offs. The primary endpoint was early SSTR-targeted PET-based progression after up to four consecutive PRRT cycles, dichotomized as progressive disease versus disease control, which was available in 301 patients.</p><p><strong>Results: </strong>Early PET-based progression occurred in 24/301 patients (8.0%). Traditional quantity-based body composition parameters were not associated with early progression. Baseline myosteatosis was present in only 8/301 patients (2.7%) and showed a nominal association with early progression in univariable analysis (OR 7.8, 95% CI 1.74-34.78; p = 0.0073), but this association did not remain significant after Benjamini-Hochberg correction for multiple testing (FDR-adjusted p = 0.1073). In a separately specified baseline-adjusted model, myosteatosis remained nominally associated with early progression (OR 8.1, 95% CI 1.69-38.75; p = 0.0090). In an exploratory model additionally including the number of completed PRRT cycles as a post-baseline treatment-exposure variable, the association was attenuated and narrowly missed conventional statistical significance (OR 5.7, 95% CI 0.97-32.86; p = 0.0538).</p><p><strong>Conclusion: </strong>Traditional quantity-based body composition parameters were not associated with early PET-based progression after PRRT. Although baseline myosteatosis showed a nominal association with early progression, this finding was based on only eight patients and did not remain significant after correction for multiple testing. The results should therefore be regarded as exploratory and hypothesis-generating and do not establish clinical utility of myosteatosis for individual risk stratification.</p>","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148982021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reduced ¹³N-Ammonia PET Myocardial Flow Reserve and Heart-Failure-Related Risk Independent of Relative Ischemia in Chronic Coronary Syndrome.","authors":"Yoshimitsu Fukushima, Rika Kobayashi, Kenji Yodogawa, Shiori Shimizu, Shogo Imai, Hiromitsu Hayashi, Shinichiro Kumita","doi":"10.1007/s00259-026-08183-9","DOIUrl":"https://doi.org/10.1007/s00259-026-08183-9","url":null,"abstract":"<p><strong>Purpose: </strong>This study evaluated whether uncorrected global myocardial flow reserve (MFR) below 2.0 on ¹³N-ammonia PET stratified risk in chronic coronary syndrome (CCS), and how rate-pressure-product (RPP) correction reclassified patients.</p><p><strong>Methods: </strong>Consecutive adults with suspected or established CCS undergoing ¹³N-ammonia PET/CT at a single Japanese center were retrospectively studied. Uncorrected global MFR below 2.0 was the primary exposure, with RPP-corrected MFR reported alongside. The primary endpoint was a hard non-revascularization composite of death, non-fatal myocardial infarction, heart-failure hospitalization, or malignant ventricular arrhythmia. The pre-specified Cox model, stratified by scanner generation, adjusted for age, sex, and summed difference score.</p><p><strong>Results: </strong>Of 168 patients, 102 (60.7%) had MFR below 2.0, with higher rest and lower stress flow (P = 0.001 and P < 0.001). Over a median 3.5 years, the endpoint occurred in 28 of 102 (27.5%) versus 5 of 66 (7.6%; log-rank P < 0.001). In the primary model, MFR below 2.0 remained independently associated with the endpoint (hazard ratio 4.5182, 95% CI 1.7121-11.9236, P = 0.002), and after excluding baseline heart failure (4.1693, P = 0.011). RPP correction reclassified 52 patients (31.0%), mostly downward. Event rates were 7.0% after downward reclassification and 29.0% in patients impaired on both values (four-group log-rank P = 0.003).</p><p><strong>Conclusion: </strong>Uncorrected global MFR below 2.0 identified higher-risk patients with CCS independently of relative ischemia, including those without baseline heart failure. RPP correction reclassified 43 patients below the threshold, supporting reporting of the uncorrected reserve with explicit labeling of any corrected value.</p>","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148982090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and validation of a preoperative ¹⁸F-PSMA-1007 PET/MR prognostic model for predicting biochemical recurrence in prostate cancer: a multicentre study.","authors":"Jiajia Hu, Hangxing Chunyu, Yihong Yang, Yanyan Song, Chao Cheng, Hailang Tang, Xiaoyue Chen, Ran Cheng, Jun Dai, Hongping Meng, Changjing Zuo, Jun Zhao, Biao Li","doi":"10.1007/s00259-026-08179-5","DOIUrl":"https://doi.org/10.1007/s00259-026-08179-5","url":null,"abstract":"<p><strong>Purpose: </strong>To develop and externally validate a preoperative ¹⁸F-PSMA-1007 PET/MR model for biochemical recurrence (BCR) after radical prostatectomy and assess its incremental prognostic value beyond clinical risk scores.</p><p><strong>Methods: </strong>This multicentre retrospective study included 210 patients from three centres (training, n = 150; external validation, n = 60). Predictors were selected by 10-fold cross-validated LASSO-Cox regression using the one-standard-error criterion and entered into a multivariable Cox model. Performance at 1-3 years was assessed using time-dependent AUCs, calibration, IPCW Brier scores, and decision-curve analysis. Incremental value beyond CAPRA-S was evaluated using likelihood-ratio tests (LRTs). Sensitivity analyses assessed the potential influence of persistent postoperative PSA and secondary treatment initiated before BCR.</p><p><strong>Results: </strong>Seventy-five patients experienced the study endpoint of biochemical recurrence. The final model included ADCmin-TBR, TMR, and PET/MR T-stage. Time-dependent AUCs were 0.703-0.858 in the training cohort and 0.766-0.846 in the validation cohort. DeLong tests showed no significant AUC differences from CAPRA-S; however, adding the PET/MR model improved fit at 2 and 3 years in the derivation cohort (both LRT p < 0.001) and at 3 years in the external validation cohort (LRT p = 0.031). DCA showed positive net benefit across most clinically relevant thresholds. ADCmin-TBR and TMR remained directionally stable across sensitivity analyses, whereas the T-stage effect was attenuated after treatment censoring.</p><p><strong>Conclusions: </strong>The ¹⁸F-PSMA-1007 PET/MR model provided externally validated prognostic information. It also showed incremental value beyond CAPRA-S at 3 years. Prospective validation is required before it can guide secondary-treatment decisions.</p><p><strong>Trial registration: </strong>ClinicalTrials.gov (NCT06604377) retrospectively registered on September 17, 2024.</p>","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148967160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tri-modal PSMA PET/CT-MRI-US fusion biopsy for clinically significant prostate cancer: a prospective paired diagnostic study.","authors":"Chen Huang, Lichen Jin, Yizhang Sun, Menglin Wu, Xuefeng Zhang, Xiaofeng Xu, Xuefeng He, Feng Qiu, Ximing Wang, Lingchuan Guo, Renpeng Huang, Jihui Li, Shengming Deng, Yuxin Lin, Xuedong Wei, Bin Zhang, Yuhua Huang","doi":"10.1007/s00259-026-08181-x","DOIUrl":"https://doi.org/10.1007/s00259-026-08181-x","url":null,"abstract":"<p><strong>Purpose: </strong>Multiparametric MRI (mpMRI)-ultrasound (US) fusion biopsy misses 8%-20% of clinically significant prostate cancer (csPCa), leaving a detection gap that prostate-specific membrane antigen (PSMA) PET/CT may help close. Whether incorporating PSMA into an MRI-US fusion platform improves csPCa detection has not been evaluated in a prospective paired design. We compared tri-modal PSMA PET/CT-MRI-US fusion biopsy with MRI-US fusion biopsy and systematic biopsy.</p><p><strong>Methods: </strong>In this prospective, single-center, and paired diagnostic accuracy study (STARD 2015; ChiCTR2400089436), 308 biopsy-naive men underwent tri-modal fusion biopsy, MRI-US fusion biopsy, and systematic biopsy in a single session. The primary endpoint was the absolute difference in patient-level csPCa detection (International Society of Urological Pathology grade group ≥ 2) between tri-modal and MRI-US fusion biopsies.</p><p><strong>Results: </strong>Tri-modal fusion detected 4.9% more csPCa than MRI-US fusion biopsy (95% confidence interval 2.4%-7.3%; P < 0.001; number needed to biopsy 20.5). The most significant gains were observed for PSMA-positive lesions < 10 mm (8.3%) and Prostate Imaging Reporting and Data System (PI-RADS) 4 lesions (5.8%), and this benefit persisted in multivariate generalized estimating equation models. The PSMA imaging-based risk score (area under the curve, 0.933) showed higher discrimination than the PRIMARY and molecular imaging PSMA scores. In a retrospective simulation using the test set, a risk-guided approach would have avoided approximately 42% of biopsies while missing 2.3% of csPCa. Limitations include the single-center design and the small test set.</p><p><strong>Conclusion: </strong>Tri-modal fusion was superior to MRI-US fusion biopsy in detecting csPCa, particularly in small PSMA-positive and PI-RADS 4 lesions. A PSMA-derived risk score enabled effective stratification, and in the test set, a simulated risk-guided approach showed potential for biopsy reduction. These findings require multicenter validation before clinical adoption.</p><p><strong>Trial registration: </strong>ChiCTR2400089436 (Chinese Clinical Trial Registry, http://www.chictr.org.cn/ , registered 2024-09-09).</p>","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correlation of ⁶⁸Ga-PSMA-11 PET/CT biodistribution with PSMA expression by immunohistochemistry in patients with HCC: A pilot prospective monocentric study.","authors":"L Vetrone, E Prosperi, E Prosperi, F Vasuri, A Degiovanni, V Allegri, P Castellucci, L Zanoni, Cristina Nanni, M Renzulli, V Lucidi, A Cattabriga, C Malizia, M Ravaioli, M Cescon, S Fanti, A Farolfi","doi":"10.1007/s00259-026-08110-y","DOIUrl":"https://doi.org/10.1007/s00259-026-08110-y","url":null,"abstract":"<p><strong>Purpose: </strong>Hepatocellular carcinoma (HCC) is a heterogeneous malignancy with limited diagnostic and prognostic tools beyond conventional imaging modalities such as CT and ceMRI. Prostate-specific membrane antigen (PSMA) expression, observed in the neoangiogenic endothelial cells of HCC, has emerged as a potential target. This study evaluated the correlation between PSMA biodistribution using [⁶⁸Ga]Ga-PSMA-11 positron emission tomography (PSMA PET/CT) and PSMA expression by immunohistochemistry (IHC) in surgical HCC patients. Secondary aim was to assess the diagnostic performance of PSMA PET/CT in this prospective cohort.</p><p><strong>Methods: </strong>This prospective monocentric study enrolled patients with suspected HCC undergoing curative-intent liver resection or transplantation. All participants underwent ceMRI and [⁶⁸Ga]Ga-PSMA-11 PET/CT within a 3-month interval, with imaging results correlated to postoperative histopathology and IHC for PSMA expression. Semi-quantitative PET parameters were analyzed alongside tumor grade, vascular invasion, and IHC metrics.</p><p><strong>Results: </strong>Eligible patients were 39, of those 31 were treated surgically. 27/31 (87%) showed PSMA uptake on PET/CT, with a median SUVmax of 12.6 (IQR10.2-16.5). According to IHC intensity analysis, PSMA was expressed in 22/24 (91.6%) of HCC. High PSMA uptake correlated with strong PSMA expression in tumor-associated vasculature (p = 0.028). No significant correlations were found between PET parameters and histological features, such as Edmondson grade or vascular invasion (p > 0.05).</p><p><strong>Conclusions: </strong>PSMA PET/CT offers robust diagnostic accuracy for HCC and correlates with vascular PSMA expression, suggesting potential utility in preoperative staging. These findings support the further exploration of PSMA imaging as a biomarker for HCC.</p>","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148967176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radium-223 decreases PD-L1 expression in bone metastases: A study with [⁸⁹Zr]Zr-atezolizumab PET and immunohistological correlation.","authors":"Sui Wai Ling, Anouk de Jong, Mark Gorris, Marcel Segbers, Laura Graven, Marjolein van Driel, Geert van Leenders, Khrystany Isebia, Marjolijn Lub- de Hooge, Paul Hamberg, Niven Mehra, Mandy van Brakel, Ronald de Wit, Reno Debets, Elisabeth de Vries, Tessa Brabander, Jolanda de Vries, Astrid van der Veldt","doi":"10.1007/s00259-026-08175-9","DOIUrl":"https://doi.org/10.1007/s00259-026-08175-9","url":null,"abstract":"<p><strong>Purpose: </strong>Most patients with metastatic castration-resistant prostate cancer (mCRPC) do not benefit from treatment with immune checkpoint inhibitors targeting programmed cell death (ligand) 1 (PD-(L)1). Radiation might improve response to immunotherapy by increasing the immunogenicity of prostate cancer. The objective of this study was to investigate radium-223-mediated changes in the micro- and macroenvironment of mCRPC.</p><p><strong>Methods: </strong>In this prospective, multicenter study (ICTRP NL-OMON26890), 28 patients with mCRPC and predominantly bone metastases were treated with radium-223, according to standard-of-care. Primary endpoint was failure-free survival (FFS). Imaging included sequential positron emission tomography (PET) with gallium-68 prostate-specific membrane antigen (⁶⁸Ga-PSMA) and zirconium-89 atezolizumab (⁸⁹Zr-atezolizumab) to quantify whole-body expression of PD-L1 in vivo (SUV_mean/max). Paired PET analysis included nine patients. The immune status of patients was characterized in biopsies from bone metastases and in blood using (multiplex) immunohistochemistry (IHC) and flow cytometry, respectively. Sequential biopsy analysis included two patients.</p><p><strong>Results: </strong>⁸⁹Zr-atezolizumab uptake in ⁶⁸Ga-PSMA positive bone metastases showed high intra- and inter-patient heterogeneity. In the total volume of ⁶⁸Ga-PSMA-positive bone lesions, the median SUV_mean of ⁸⁹Zr-atezolizumab was 2.5 (IQR 0.9-3.4) at baseline and 0.9 (IQR 0.5-2.5) after three cycles of radium-223, which was higher than the physiological uptake in bone marrow at baseline and after treatment with radium-223. After three cycles of radium-223, ⁸⁹Zr-atezolizumab uptake decreased in bone metastases, independent of response on ⁶⁸Ga-PSMA PET, and the number of lymphocytes in tumor tissue and blood decreased concomitantly.</p><p><strong>Conclusions: </strong>Treatment of mCRPC bone metastases with radium-223 results in a significant decrease of in vivo PD-L1-expression on PET imaging and a decrease in immune cells in bone metastases and blood. These findings indicate that treatment with alpha emitting radium-223 alters the immune microenvironment, thereby potentially reducing the efficacy of PD-(L)1 inhibitors.</p>","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148944511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prognostic value and diagnostic performance of nectin-4-targeted [⁶⁸Ga]Ga-FZ-NR-1 PET/CT versus [¹⁸F]FDG in recurrent or metastatic triple-negative breast cancer.","authors":"Ye Li, Yuyun Sun, Li Sun, Dongliang Wang, Xiaoyu Pan, Xiaoping Xu, Shaoli Song","doi":"10.1007/s00259-026-08177-7","DOIUrl":"https://doi.org/10.1007/s00259-026-08177-7","url":null,"abstract":"<p><strong>Purpose: </strong>Nectin-4 has emerged as an attractive diagnostic and therapeutic target in a wide range of malignancies. Herein, we aimed to evaluate the clinical utility of a novel Nectin-4-targeted radiotracer, [⁶⁸Ga]Ga-FZ-NR-1, for non-invasive whole-body mapping, head-to-head diagnostic comparison with [¹⁸F]FDG, and survival prediction in recurrent or metastatic triple-negative breast cancer (TNBC).</p><p><strong>Methods: </strong>40 patients with recurrent or metastatic TNBC who underwent [⁶⁸Ga]Ga-FZ-NR-1 and [¹⁸F]FDG PET/CT within 1 week were enrolled in this clinical translational study. Diagnostic performance was compared using the McNemar test. The survival analyses were performed using the Kaplan-Meier method.</p><p><strong>Results: </strong>[⁶⁸Ga]Ga-FZ-NR-1 PET/CT revealed high intra-patient spatial heterogeneity of Nectin-4 expression, yielding a median inter-lesion fold difference of 3.10 and a median coefficient of variation of 31.70%. Although a higher SUV_max was observed with [¹⁸F]FDG, [⁶⁸Ga]Ga-FZ-NR-1 achieved a significantly higher tumor-to-background ratio across various metastatic sites. Therefore, [⁶⁸Ga]Ga-FZ-NR-1 PET/CT detected more lesions than [¹⁸F]FDG PET/CT and showed better sensitivity and specificity (98.13% vs.93.46% and 68.63% vs. 27.45%, respectively). Furthermore, high baseline mean MTV₄₀ ([⁶⁸Ga]Ga-FZ-NR-1) and HI ([⁶⁸Ga]Ga-FZ-NR-1) predicted significantly shorter progression-free survival (P = 0.009) and overall survival (P = 0.008), respectively.</p><p><strong>Conclusion: </strong>[⁶⁸Ga]Ga-FZ-NR-1 PET/CT demonstrates improved diagnostic performance and independent prognostic value compared to [¹⁸F]FDG in recurrent or metastatic TNBC. These hypothesis-generating findings suggest that it holds potential as a non-invasive imaging biomarker to aid future risk stratification and patient selection for Nectin-4-targeted therapies.</p>","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148955083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Practices and barriers in PET/CT use for critically ill patients: an international survey.","authors":"Camilla Genovese, Jean-François Timsit, Michael Thy","doi":"10.1007/s00259-026-08172-y","DOIUrl":"https://doi.org/10.1007/s00259-026-08172-y","url":null,"abstract":"<p><strong>Purpose: </strong>2-deoxy-2-[18F] fluoro-D-glucose (FDG) Positron Emission Tomography/Computed Tomography ([18F]-FDG-PET/CT) offers high diagnostic sensitivity for occult infection, malignancy and inflammatory processes - conditions that frequently complicate critical‑care patients. Despite this potential, routine use of [18F]-FDG-PET/CT in the intensive care unit (ICU) remains sporadic and there are no formal guidelines to direct its application. The objective of the study is to describe current international practice, identify barriers to implementation, and provide a data‑driven foundation for future consensus recommendations on [18F]-FDG-PET/CT use in ICU patients.</p><p><strong>Methods: </strong>An electronic questionnaire was disseminated worldwide through the European Society of Intensive Care Medicine (ESICM) and the European Association of Nuclear Medicine (EANM). The survey collected demographic information, hospital characteristics, availability and location of nuclear‑medicine services, clinical indications for [18F]-FDG-PET/CT in critically ill patients, frequency of use, workflow organization, and perceived obstacles. Forty‑one respondents from 16 countries completed the survey.</p><p><strong>Results: </strong>Most participants worked in university hospitals (63%) and specialised either in ICU care (71%) or nuclear imaging (29%). A nuclear‑medicine department (NMD) was available in 78% of centres, but only 60% were co‑located with the ICU. [18F]-FDG-PET/CT was performed infrequently: 43% of users performed 1-5 scans per year and a fourth performed 1-2 scans per month. The use of PET/CT as primary diagnostic technique was infection (74%), followed by malignancy (57%) and fever of unknown origin (49%). Radiotracer administration occurred mainly in the NMD (77%) and specific dietary preparation protocols were present in only 50% of sites. Reported barriers included lack of standardised protocols, prolonged procedure duration, limited imaging slots, ambiguous indications, insufficient staff expertise, and logistical difficulties transporting unstable ICU patients.</p><p><strong>Conclusion: </strong>This international survey reveals marked heterogeneity in [18F]-FDG-PET/CT utilisation and significant practical obstacles in the ICU setting. The data highlight an unmet need for consensus guidelines and streamlined workflows to optimise the diagnostic value of [18F]-FDG-PET/CT in critical‑care patients. Findings will inform forthcoming joint recommendations by ESICM and EANM, ultimately aiming to enhance patient outcomes through evidence‑based imaging protocols.</p>","PeriodicalId":11909,"journal":{"name":"European Journal of Nuclear Medicine and Molecular Imaging","volume":" ","pages":""},"PeriodicalIF":7.6,"publicationDate":"2026-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148955076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}