Frontiers in nuclear medicine (Lausanne, Switzerland)最新文献

{"title":"Radiolabeled iron oxide nanoparticles functionalized with PSMA/BN ligands for dual-targeting of prostate cancer","authors":"Danae Efremia Bajwa, Evangelia-Alexandra Salvanou, Maria Theodosiou, Theodora S. Koutsikou, Eleni K. Efthimiadou, Penelope Bouziotis, Christos Liolios","doi":"10.3389/fnume.2023.1184309","DOIUrl":"https://doi.org/10.3389/fnume.2023.1184309","url":null,"abstract":"Introduction Prostate cancer (PCa) is the second most frequent cancer diagnosis in men and the fifth leading cause of death worldwide. Prostate Specific Membrane Antigen (PSMA) and Gastrin Releasing Peptide (GRP) receptors are overexpressed in PCa. In this study, we have developed iron oxide nanoparticles (IONs) functionalized with the Prostate Specific Membrane Antigen (PSMA) and Gastrin Releasing Peptide (GRP) ligands for dual targeting of Prostate cancer. Methods IONs were developed with a thin silica layer on their surface with MPTES (carrying -SH groups, IONs-SH), and they were coupled either with a pharmacophore targeting PSMA (IONs-PSMA) or with bombesin peptide (IONs-BN), targeting GRP receptors, or with both (IONs-PSMA/BN). The functionalized IONs were characterized for their size, zeta potential, and efficiency of functionalization using dynamic light scattering (DLS) and Fourier-Transform Infrared Spectroscopy (FT-IR). All the aforementioned types of IONs were radiolabeled directly with Technetium-99m ( 99m Tc) and evaluated for their radiolabeling efficiency, stability, and binding ability on two different PCa cell lines (PC3 and LNCaP). Results and Discussion The MTT assay demonstrated low toxicity of the IONs against PC3 and LNCaP cells, while the performed wound-healing assay further proved that these nanostructures did not affect cellular growth mechanisms. The observed hemolysis ratio after co-incubation with red blood cells was extremely low. Furthermore, the 99m Tc-radiolabeled IONs showed good stability in human serum, DTPA, and histidine, and high specific binding rates in cancer cells, supporting their future utilization as potential diagnostic tools for PCa with Single Photon Emission Computed Tomography (SPECT) imaging.","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136314063","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":"Multicentric 68Ga-PSMA PET radiomics for treatment response assessment of 177Lu-PSMA-617 radioligand therapy in patients with metastatic castration-resistant prostate cancer","authors":"Robin Gutsche, Gizem Gülmüs, Felix M. Mottaghy, Florian Gärtner, Markus Essler, Dirk von Mallek, Hojjat Ahmadzadehfar, Philipp Lohmann, Alexander Heinzel","doi":"10.3389/fnume.2023.1234853","DOIUrl":"https://doi.org/10.3389/fnume.2023.1234853","url":null,"abstract":"Objective The treatment with 177 Lutetium PSMA ( 177 Lu-PSMA) in patients with metastatic castration-resistant prostate cancer (mCRPC) has recently been approved by FDA and EMA. Since treatment success is highly variable between patients, the prediction of treatment response and identification of short- and long-term survivors after treatment could help to tailor mCRPC diagnosis and treatment accordingly. The aim of this study is to investigate the value of radiomics parameters extracted from pretreatment 68 Ga-PSMA PET images for prediction of treatment response. Methods Forty-five mCRPC patients treated with 177 Lu-PSMA-617 from two university hospital centers were retrospectively reviewed for this study. Radiomics features were extracted from the volumetric segmentations of metastases in the bone. A random forest model was trained and validated to predict treatment response based on age and conventionally used PET parameters, radiomics features, and combinations thereof. Further, overall survival was predicted by using the identified radiomics signature and compared to a Cox regression model based on age and PET parameters. Results The machine learning model based on a combined radiomics signature of three features and patient age achieved an AUC of 0.82 in 5-fold cross validation and outperformed models based on age and PET parameters or radiomics features (AUC, 0.75 and 0.76, respectively). A Cox regression model based on this radiomics signature showed the best performance to predict the overall survival (C-index, 0.67). Conclusion Our results demonstrate that a machine learning model to predict response to 177 Lu-PSMA treatment based on a combination of radiomics and patient age outperforms a model based on age and PET parameters. Moreover, the identified radiomics signature based on pretreatment 68 Ga-PSMA PET images might be able to identify patients with an improved outcome and serve as a supportive tool in clinical decision making.","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134911457","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":"Post-acquisition standardization of positron emission tomography images","authors":"Aliasghar Mortazi, Jayaram K. Udupa, Dewey Odhner, Yubing Tong, Drew A. Torigian","doi":"10.3389/fnume.2023.1210931","DOIUrl":"https://doi.org/10.3389/fnume.2023.1210931","url":null,"abstract":"Purpose Tissue radiotracer activity measured from positron emission tomography (PET) images is an important biomarker that is clinically utilized for diagnosis, staging, prognostication, and treatment response assessment in patients with cancer and other clinical disorders. Using PET image values to define a normal range of metabolic activity for quantification purposes is challenging due to variations in patient-related factors and technical factors. Although the formulation of standardized uptake value (SUV) has compensated for some of these variabilities, significant non-standardness still persists. We propose an image processing method to substantially mitigate these variabilities. Methods The standardization method is similar for activity concentration (AC) PET and SUV PET images with some differences and consists of two steps. The calibration step is performed only once for each of AC PET or SUV PET, employs a set of images of normal subjects, and requires a reference object, while the transformation step is executed for each patient image to be standardized. In the calibration step, a standardized scale is determined along with 3 key image intensity landmarks defined on it including the minimum percentile intensity s min , median intensity s m , and high percentile intensity s max . s min and s m are estimated based on image intensities within the body region in the normal calibration image set. The optimal value of the maximum percentile β corresponding to the intensity s max is estimated via an optimization process by using the reference object to optimally separate the highly variable high uptake values from the normal uptake intensities. In the transformation step , the first two landmarks—the minimum percentile intensity p α ( I ), and the median intensity p m ( I )—are found for the given image I for the body region, and the high percentile intensity p β ( I ) is determined corresponding to the optimally estimated high percentile value β . Subsequently, intensities of I are mapped to the standard scale piecewise linearly for different segments. We employ three strategies for evaluation and comparison with other standardization methods: (i) comparing coefficient of variation (CV O ) of mean intensity within test objects O across different normal test subjects before and after standardization; (ii) comparing mean absolute difference (MD O ) of mean intensity within test objects O across different subjects in repeat scans before and after standardization; (iii) comparing CV O of mean intensity across different normal subjects before and after standardization where the scans came from different brands of scanners. Results Our data set consisted of 84 FDG-PET/CT scans of the body torso including 38 normal subjects and two repeat-scans of 23 patients. We utilized one of two objects—liver and spleen—as a reference object and the other for testing. The proposed standardization method reduced CV O and MD O by a factor of 3–8 in comparison to ","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135884210","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":"To tell or not to tell … the patient about potential harm.","authors":"Timothy L Bartholow","doi":"10.3389/fnume.2023.1258960","DOIUrl":"10.3389/fnume.2023.1258960","url":null,"abstract":"<p><p>Extravasation, as distinct from infiltration, is when a potentially toxic agent (e.g., radiographic contrast, chemotherapy, anesthesia or radionuclide) is unintentionally administered to the surrounding tissue instead of directly into the vein. There is an expectation for vascular access in interventional medicine across nearly all specialties that this high frequency, study/treatment critical procedure needs to occur with rare failure and that this failure rate should be characterized in quality assurance. This opinion piece, written by a family practitioner who has served as the chief medical officer for a not-for-profit payer, reflects on our responsibility to be aware as clinicians of known potential harm and disclose to patients before a risk has occurred and if harm has occurred. In this paper, clinical obligations of reporting will be reviewed, which are necessary to maintain and enhance our trust with our patients. In the second half, the perspectives of a not-for-profit payer chief medical officer will be considered.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":" ","pages":"1258960"},"PeriodicalIF":0.0,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11440947/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48587052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Case report: 18F-FDG PET-CT findings in Bickerstaff encephalitis before and after treatment.","authors":"Nora E Kerik-Rotenberg, Jocelyn Cruz-Perez, Ivan E Diaz-Meneses, Alfredo Javier Aguirre Enriquez, Sarah Elizabeth González Ríos, Emilly A Cortés-Mancera, Fabio Sinisterra Solís, Francisco Romero Castellanos, Edwin Steven Vargas-Canas, Jesús Ramirez-Bermudez","doi":"10.3389/fnume.2023.1235173","DOIUrl":"10.3389/fnume.2023.1235173","url":null,"abstract":"","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":" ","pages":"1235173"},"PeriodicalIF":0.0,"publicationDate":"2023-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11440965/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42856277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Theranostics in breast cancer.","authors":"M Vorster, B P Hadebe, M M Sathekge","doi":"10.3389/fnume.2023.1236565","DOIUrl":"10.3389/fnume.2023.1236565","url":null,"abstract":"<p><strong>Introduction: </strong>Breast cancer is a complex disease and constitutes the leading cause of cancer in women globally. Conventional treatment modalities include surgery, chemotherapy, radiation therapy, and hormonal therapy; all of these have their limitations and often result in significant side effects or toxicity. Targeted radionuclide therapy based on a theranostic approach has been successfully applied in several malignancies, such as prostate cancer, thyroid cancer, and neuro-endocrine tumours. Several studies have also highlighted the potential of theranostic applications in breast cancer.</p><p><strong>Aim: </strong>This review aims to provide an overview of the most promising current and future theranostic approaches in breast cancer.</p><p><strong>Discussion: </strong>The discussion includes pre-clinical as well as clinical data on some of the most successful targets used to date. Examples of potential theranostic approaches include those targeting the Human epidermal growth factor receptor 2 (HER2) expression, angiogenesis, aspects of the tumour microenvironment, Gastrin-releasing peptide receptor (GRPR), Prostate-specific membrane antigen (PSMA) and Chemokine receptor 4 (CXCR-4) expression. Several challenges to widespread clinical implementation remain, which include regulatory approval, access to the various radiopharmaceuticals and imaging technology, cost-effectiveness, and the absence of robust clinical data.</p><p><strong>Conclusion: </strong>Theranostic approaches have the potential to greatly improve diagnosis, treatment, and outcomes for patients with breast cancer. More research is needed to fully explore the potential of such approaches and to identify the best potential targets, considering feasibility, costs, efficacy, side effects and outcomes.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":" ","pages":"1236565"},"PeriodicalIF":0.0,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11440857/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46884466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Case report: Peptide receptor radioligand therapy in metastatic pediatric neuroendocrine tumors.","authors":"Khanyisile Hlongwa, Olumayowa Kolade, Abdulilah Alnabulsi, Rachelle Steyn, Anita Brink, Vikas Prasad, Stuart More","doi":"10.3389/fnume.2023.1193880","DOIUrl":"10.3389/fnume.2023.1193880","url":null,"abstract":"<p><p>Neuroendocrine tumors (NETs) are not commonly diagnosed in children. Metastatic NETs tend to have poor outcomes, and this is seen in adult and pediatric populations. The role of somatostatin receptor imaging using [⁶⁸Ga]Ga-DOTA-TATE for imaging and peptide receptor radionuclide therapy (PRRT) with [¹⁷⁷Lu]Lu-DOTA-TATE in children is currently not well established. The guidelines for treating pediatric neuroendocrine tumors are still lacking. Extensive trials have been conducted in adult patients and have demonstrated improved survival in metastatic NETs with PRRT using [¹⁷⁷Lu]Lu-DOTA-TATE. We present two pediatric patients with metastatic NETs who were imaged with [⁶⁸Ga]Ga-DOTA-TATE PET/CT and treated with [¹⁷⁷Lu]Lu-DOTA-TATE therapy.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":" ","pages":"1193880"},"PeriodicalIF":0.0,"publicationDate":"2023-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11440991/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42327936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Critique and discussion of \"Multicenter evaluation of frequency and impact of activity infiltration in PET imaging, including microscale modeling of skin-absorbed dose\".","authors":"Josh Knowland","doi":"10.3389/fnume.2023.1240162","DOIUrl":"10.3389/fnume.2023.1240162","url":null,"abstract":"","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":" ","pages":"1240162"},"PeriodicalIF":0.0,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11440859/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47872118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A systematic evaluation of five different image-derived input functions for the clinical implementation of ¹⁸F-NaF bone PET/CT in patients with chronic kidney disease-mineral and bone disorder.","authors":"Jørn Theil, Marie Houmaa Vrist, Jesper Nørgaard Bech, Claire Anne Fynbo","doi":"10.3389/fnume.2023.1235800","DOIUrl":"10.3389/fnume.2023.1235800","url":null,"abstract":"<p><strong>Introduction: </strong>The aim of this study was to investigate the impact of the use of varying input parameters on resulting bone plasma clearance (<i>K_i</i> ) and other kinetic modelling parameters in a group of patients with chronic kidney disease-mineral and bone disorder (CKD-MBD).</p><p><strong>Methods: </strong>Raw PET/CT data and blood data were systematically analyzed using five different VOIs for the input functions in the left ventricle and in the thoracic aorta. Standardized VOIs were placed in four thoracic vertebrae and the results pooled and averaged. The basic image-derived input functions (IDIFs) were corrected for partial volume effect and spill-over and modified by substitution of the terminal image exponential with the corresponding plasma-exponentials derived from blood samples. <i>K_i</i> was then calculated using both a non-linear regression (NLR) analysis and a graphical Patlak analysis and compared.</p><p><strong>Results: </strong>Our original results were reproducible with an inter-observer difference of approximately 6%. The correction factors varied with the VOI volumes from 0.73 ± 0.17 for the largest LV-VOI (48.7 ± 25.3 cm³) to 0.99 ± 0.10 for the AO-VOI (3.4 ± 1.2 cm³). The mean NLR-<i>K_i</i> results varied between 0.0378 ± 0.0112 and 0.0432 ± 0.0095 ml/min ml^-1 with a fixed vB and 0.0408 ± 0.0111 and 0.045 ± 0.0102 ml/min ml^-1 with a free-fitted vB. The corresponding Patl-<i>K_i</i> -results varied between 0.0302 ± 0.0071 and 0.0325 ± 0.0070 ml/min ml^-1, having lesser differences and variances. The input functions with least variance and mean differences compared with NLR results were derived from the left ventricle with a VOI volume of 19.2 ± 11.3 cm³ corrected for PVE and Bg with a mean <i>K_i</i> -difference: 0.0097 ± 0.0370 ml/min ml^-1 and 95% confidence limits (-0.023 to 0.004).</p><p><strong>Conclusions: </strong>Our results indicated that a VOI with a volume of approximately 20 cm³ with a correction factor of 0.83 ± 0.13 results in Patlak results with the least variance and difference compared with the NLR results. The use of free-fitted vB in the NLR analysis showed the most robust results in all input series. The Patlak results were in comparison generally lower than the NLR results (-17.3% to -23.4%) but very robust across the various input series and with results comparable to previously published data and are therefore recommended for future analysis.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":" ","pages":"1235800"},"PeriodicalIF":0.0,"publicationDate":"2023-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11440843/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47993058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gallium-68 fibroblast activation protein inhibitor positron emission tomography in cardiovascular disease.","authors":"Dineo Mpanya, Mike Sathekge, Eric Klug, Jenna Damelin, Stuart More, Bawinile Hadebe, Mariza Vorster, Nqoba Tsabedze","doi":"10.3389/fnume.2023.1224905","DOIUrl":"10.3389/fnume.2023.1224905","url":null,"abstract":"<p><p>Gallium-68 fibroblast activation protein inhibitor [(⁶⁸Ga)Ga-FAPI] is a new radiopharmaceutical positioning itself as the preferred agent in patients with malignant tumours, competing with 2-Deoxy-2-[18F]fluoro-d-glucose [2-(¹⁸F)FDG] using positron emission tomography (PET). While imaging oncology patients with [⁶⁸Ga]Ga-FAPI PET, incidental uptake of [⁶⁸Ga]Ga-FAPI has been detected in the myocardium. This review summarises original research studies associating the visualisation of FAPI-based tracers in the myocardium with underlying active cardiovascular disease.</p>","PeriodicalId":73095,"journal":{"name":"Frontiers in nuclear medicine (Lausanne, Switzerland)","volume":" ","pages":"1224905"},"PeriodicalIF":0.0,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11440833/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43169872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}