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The dynamics and correlation of ctDNA and PET-CT baseline tumor parameters in patients with diffuse large B-cell lymphoma. Methods: 63 patients with diffuse large B cell lymphoma treated by hematology department from 2020.1 to 2022.2 were in the observation group, and 22 non-tumor patients were in the matched group. Relevant indicators were determined and compared, and the correlation was analyzed. Result: The ctDNA, SUVmax, SUVmean, TMTV, and TLG were higher than those in the observation group (P<0.05); ctDNA, SUVmax, SUVmean, TMTV, TLG gradually increased in Ann-Arbor stage and decreased in different treatment periods (P<0.05); Spearman correlation showed positive cDNA with SUVmax, SUVmean, TMTV, and TLG (P<0.05). Conclusion: The baseline tumor parameters of ctDNA and PET-CT in patients with diffuse large B-cell lymphoma increase with the increase of Ann Arbor stage, while decrease with the increase of chemotherapy course. ctDNA is positively correlated with SUVmax, SUVmean, TMTV, TLG. [ABSTRACT FROM AUTHOR]

Abstract Background Multiple models intravoxel incoherent motion (IVIM) based 18F-fluorodeoxyglucose positron emission tomography-magnetic resonance(18F-FDG PET/MR) could reflect the microscopic information of the tumor from multiple perspectives. However, its value in the prognostic assessment of non-small cell lung cancer (NSCLC) still needs to be further explored. Objective To compare the value of 18F-FDG PET/MR metabolic parameters and diffusion parameters in the prognostic assessment of patients with NSCLC. Meterial and methods Chest PET and IVIM scans were performed on 61 NSCLC patients using PET/MR. The maximum standard uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), diffusion coefficient (D), perfusion fraction (f), pseudo diffusion coefficient (D*) and apparent diffusion coefficient (ADC) were calculated. The impact of SUVmax, MTV, TLG, D, f, D*and ADC on survival was measured in terms of the hazard ratio (HR) effect size. Overall survival time (OS) and progression-free survival time (PFS) were evaluated with the Kaplan–Meier and Cox proportional hazard models. Log-rank test was used to analyze the differences in parameters between groups. Results 61 NSCLC patients had an overall median OS of 18 months (14.75, 22.85) and a median PFS of 17 months (12.00, 21.75). Univariate analysis showed that pathological subtype, TNM stage, surgery, SUVmax, MTV, TLG, D, D* and ADC were both influential factors for OS and PFS in NSCLC patients. Multifactorial analysis showed that MTV, D* and ADC were independent predicting factors for OS and PFS in NSCLC patients. Conclusion MTV, D* and ADC are independent predicting factors affecting OS and PFS in NSCLC patients. 18F-FDG PET/MR-derived metabolic parameters and diffusion parameters have clinical value for prognostic assessment of NSCLC patients.

Background: Increased thermogenic activity has shown to be a promising target for treating and preventing obesity and type 2 diabetes (T2DM). Little is known about the muscular influence on nonshivering thermogenesis (NST), and it remains unclear whether physical training and potential metabolic improvements could be associated with changes in this type of thermogenic activity. Objective: The present study aimed to assess muscular NST activity in overweight and T2DM before and after a combined training period (strength training followed by aerobic exercise). Methods: Nonshivering cold‐induced 18‐fluoroxyglucose positron emission computed tomography (18F‐FDG PET/CT) was performed before and after 16 weeks of combined training in 12 individuals with overweight and T2DM. The standard uptake value (SUV) of 18F‐FDG was evaluated in skeletal muscles, the heart and the aorta. Results: Muscles in the neck region exhibit higher SUV pre‐ and posttraining. Furthermore, a decrease in glucose uptake by the muscles of the lower and upper extremities and in the aorta was observed after training when adjusted for brown adipose tissue (BAT). These pre–post effects are accompanied by increased cardiac SUV and occur concurrently with heightened energy expenditure and metabolic improvements. Conclusions: Muscles in the neck region have greater metabolic activity upon exposure to cold. In addition, combined training appears to induce greater NST, favoring the trunk and neck region compared to limbs based on joint work and adaptations between skeletal muscles and BAT. [ABSTRACT FROM AUTHOR]

Background: Multiple models intravoxel incoherent motion (IVIM) based 18F-fluorodeoxyglucose positron emission tomography-magnetic resonance(18F-FDG PET/MR) could reflect the microscopic information of the tumor from multiple perspectives. However, its value in the prognostic assessment of non-small cell lung cancer (NSCLC) still needs to be further explored. Objective: To compare the value of 18F-FDG PET/MR metabolic parameters and diffusion parameters in the prognostic assessment of patients with NSCLC. Meterial and methods: Chest PET and IVIM scans were performed on 61 NSCLC patients using PET/MR. The maximum standard uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), diffusion coefficient (D), perfusion fraction (f), pseudo diffusion coefficient (D*) and apparent diffusion coefficient (ADC) were calculated. The impact of SUVmax, MTV, TLG, D, f, D*and ADC on survival was measured in terms of the hazard ratio (HR) effect size. Overall survival time (OS) and progression-free survival time (PFS) were evaluated with the Kaplan–Meier and Cox proportional hazard models. Log-rank test was used to analyze the differences in parameters between groups. Results: 61 NSCLC patients had an overall median OS of 18 months (14.75, 22.85) and a median PFS of 17 months (12.00, 21.75). Univariate analysis showed that pathological subtype, TNM stage, surgery, SUVmax, MTV, TLG, D, D* and ADC were both influential factors for OS and PFS in NSCLC patients. Multifactorial analysis showed that MTV, D* and ADC were independent predicting factors for OS and PFS in NSCLC patients. Conclusion: MTV, D* and ADC are independent predicting factors affecting OS and PFS in NSCLC patients. 18F-FDG PET/MR-derived metabolic parameters and diffusion parameters have clinical value for prognostic assessment of NSCLC patients. [ABSTRACT FROM AUTHOR]

Follicular lymphoma (FL) is a non-Hodgkin lymphoma with complex biological properties and heterogeneous clinical manifestations. FL mainly involves lymph nodes throughout the body, and about 7% of patients in China will histologically transform into other aggressive lymphoma. Therefore, there are great differences in the treatment strategies and prognosis of patients with FL. With the development of molecular imaging technology, PET/CT fusion molecular ima-ging can not only identify small lesions in vivo more accurately, but also provide metabolic information of lesions. A number of studies and guidelines have affirmed the important value of 18F-fluorodeoxyglucose-positron emission computed tomography (18F-FDG PET/CT) image features in the whole process of FL disease diagnosis, grading and staging, evaluation of efficacy and prediction of survival outcomes. However, due to the lack of uniform standards for image scanning and threshold definition, the specific prognostic efficacy of PET/CT parameters in FL patients in different studies is still controversial. This article reviews the recent progress in early identification of high-risk follicular lymphoma patients and prognosis prediction of FL patients based on PET/CT image features at home and abroad, further affirms the value of 18F-FDG PET/CT in judging the possibility of histological transformation of FL and evaluating the survival outcome of FL patients. To assist to optimize the clinical diagnosis and treatment decisions, improve the treatment efficiency and prognosis of FL patients.

This article discusses the use of phosphorus-32 (32P) microparticles for the treatment of locally advanced pancreatic ductal adenocarcinoma (PDAC). PDAC is a leading cause of mortality globally, and current treatment options for inoperable cases are limited. The article highlights the potential of internal radiation therapy (IRT) using 32P microparticles as an alternative therapeutic option. Several clinical studies have shown promising results, including reductions in tumor volume and improved disease control rates. However, further research is needed to determine the optimal timing and efficacy of this treatment approach. [Extracted from the article]

This editorial discusses the use of Pentixather, a radiopharmaceutical labeled with gallium-68, in the treatment of hematological disorders such as multiple myeloma and lymphomas. The studies reviewed showed that Pentixather radioligand therapy (RLT) was effective and tolerable in heavily pretreated patients, with neutropenia and infections being the most common adverse effects. However, further research and validation through multicenter studies are needed to fully understand the potential of Pentixather RLT in these conditions. Clinical trials are currently underway to investigate the efficacy of different radioligands in managing lymphomatous central nervous system involvement and multiple myeloma. [Extracted from the article]

Dopamine D3 receptors are closely related to drug addiction, Parkinson’s disease (PD), schizophrenia and other neuropsychiatric diseases. PET imaging agents that target dopamine D3 receptors can noninvasively show changes in receptor density and status, thus revealing the origin and development process of disease and providing a basis for treatment. However, because dopamine D3 receptors have high similarity with D2 receptors hinders the selectivity of existing D3 receptors PET imaging agents, which limits the study of the mechanism of action of dopamine D3 receptors in neural networks. It is of great significance to develop high specificity, affinity, selective D3 receptor probe for the diagnosis and treatment of diseases of the central nervous system. This article reviewed the 18F and 11C radiolabeled PET molecular probes including tetrahydropyrrole derivatives, aminotetralin derivatives and phenylpiperazines derivatives. Furthermore, the challenges in the development of D3 receptor probes also be discussed, aiming to provide valuable insights for future probe advancements.

Despite significant advances in glioma diagnosis and treatment, overall outcomes remain suboptimal. Exploring novel therapeutic avenues show promise in advancing the field. Theranostics, an evolving discipline integrating diagnosis and therapy, emerges as a particularly auspicious approach. However, an unmet need exists for glioma-associated biomarkers as theranostic targets. Immuno-positron emission tomography (Immuno-PET), a pioneering method uniting PET diagnostic precision with antibody specificity, holds potential for identifying cancer-associated biomarkers. This review aims to provide an updated overview of immuno-PET applications in gliomas. Notably, [44Sc]-CHX-A″-DTPA-Cetuximab-Fab targeting Epidermal Growth Factor Receptor (EGFR) has displayed promise in glioma xenografts, enabling potential imaging at 4 h post-injection. Similarly, [89Zr]-bevacizumab targeting vascular endothelial growth factor (VEGF) yielded encouraging results in preclinical models and a pioneering clinical trial for pediatric patients with diffuse intrinsic pontine glioma (DIPG). Several cell differentiation markers, including CD146, indicative of tumor aggressiveness, and CD11b, reflecting tumor-associated myeloid cells (TAMCs), proved effective targets for immuno-PET. Additionally, immuno-PET directed at prostate-specific antigen (PSMA) demonstrated efficacy in imaging glioma-associated neovasculature. While holding promise for precise diagnosis and treatment guidance, challenges persist in achieving target specificity and selecting suitable radionuclides. Further studies are imperative to advance the field and bridge a translational gap from bench to bedside. [ABSTRACT FROM AUTHOR]

We describe the case of a 43-year-old female with hereditary hemochromatosis, previously without cardiac issues, who presented with a severe fever (>40 to 41 °C) to our hospital. Initial assessments, including transthoracic echocardiography, showed no typical signs of infective endocarditis. A contrast-enhanced CT scan revealed a hypodense area in the right subscapular muscle, alongside pleural thicknesses. Due to the critical condition, a central venous catheter (CVC) was implanted for immediate intravenous treatment. Subsequent blood cultures, positive for Staphylococcus aureus, and transesophageal echocardiography led to a diagnosis of multivalvular infective endocarditis (MIE). Subsequently, the patient underwent positron emission tomography/computed tomography (PET/CT) with [18F]Fluorodeoxyglucose ([18F]FDG), which detected increased tracer incorporation in the muscle lesion, CVC, and pleural thicknesses. The final diagnosis was CVC infection and septic embolism to the subscapular muscle in a patient with pleuritis. This case showcases the critical role of [18F]FDG PET/CT as whole-body imaging modality in diagnosing and managing complex infective cases. [ABSTRACT FROM AUTHOR]

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Abstract Background Stage I lung adenocarcinoma is a heterogeneous group. Previous studies have shown the prognostic evaluation value of PET/CT in this cohort; however, few studies focused on stage I invasive adenocarcinoma manifesting as solid nodules. This study aimed to evaluate the recurrence risk for patients with stage I invasive lung adenocarcinoma manifesting as solid nodules based on 18F-FDG PET/CT, CT imaging signs, and clinicopathological parameters. Methods We retrospectively enrolled 230 patients who underwent 18F-FDG PET/CT examination between January 2013 and July 2019. Metabolic parameters: maximum standard uptake value (SUVmax), mean standard uptake value, tumor metabolic volume (MTV), and total tumor glucose digestion were collected. Kaplan–Meier method was used to evaluate recurrence-free survival (RFS), and the multivariate Cox proportional hazards model was used to determine the independent risk factors associated with RFS. The time-dependent receiver operating characteristic curve (ROC) method was used to calculate the optimal cutoff value of metabolic parameters. Results The 5-year RFS rate for all patients was 71.7%. Multivariate Cox analysis revealed that the International Association for the Study of Lung Cancer Pathology Committee (IASLC) pathologic grade 3 [Hazard ratio (HR), 3.96; 95% Confidence interval (CI), 1.11–14.09], the presence of cavity sign (HR 5.38; 95% CI 2.23–12.96), SUVmax (HR 1.23; 95% CI 1.13–1.33), and MTV (HR 1.05; 95% CI 1.01–1.08) were potential independent prognostic factors for RFS. Patients with IASLC grade 3, the presence of cavity sign, SUVmax > 3.9, or MTV > 5.4 cm3 were classified as high risk, while others were classified as low risk. There was a significant difference in RFS between the high-risk and low-risk groups (HR 6.04; 95% CI 2.17–16.82, P

Alzheimer's disease (AD) is a common neurodegenerative disease. The histopathological changes in AD include amyloid β‐protein (Aβ) deposition, tau tangles, neuroinflammation, and neurodegeneration. Some of the pathological changes could be shown in vivo by positron emission tomography (PET) and magnetic resonance imaging (MRI) biomarkers, which play a key role in diagnosing AD. Fluorodeoxyglucose positron emission tomography (FDG‐PET) can reflect and predict dysfunction. Aβ‐PET is sensitive for the diagnosis of early AD but cannot distinguish the severity of AD. Tau‐PET can compensate for the deficiency of Aβ‐PET. Tau tangles are positively correlated with the severity of AD and associated with cognitive impairment. Probes targeting neuroinflammation in AD have been developed, but further study is needed to validate their effectiveness. Conventional MRI performs high tissue contrast that can show structural changes and has been routinely applied in clinical practice, such as in the evaluation of cerebral atrophy. Advanced MRI sequences (such as diffusion tensor imaging, arterial spin labeling, magnetic resonance spectroscopy, blood oxygenation level dependent, and quantitative susceptibility mapping) can provide additional information beyond structure that includes brain microstructure, blood perfusion, metabolite concentration, brain activity, connections and networks between brain regions, iron deposition, etc. Integrated PET and MRI may improve the diagnostic efficiency of AD. [ABSTRACT FROM AUTHOR]

Gastroenteropancreatic neuroendocrine neoplasia (GEP-NEN) is a heterogeneous and complex group of tumors that are often difficult to classify due to their heterogeneity and varying locations. As standard radiological methods, ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography–computed tomography (PET/CT) are available for both localization and staging of NEN. Nuclear medical imaging methods with somatostatin analogs are of great importance since radioactively labeled receptor ligands make tumors visible with high sensitivity. CT and MRI have high detection rates for GEP-NEN and have been further improved by developments such as diffusion-weighted imaging. However, nuclear medical imaging methods are superior in detection, especially in gastrointestinal NEN. It is important for radiologists to be familiar with NEN, as it can occur ubiquitously in the abdomen and should be identified as such. Since GEP-NEN is predominantly hypervascularized, a biphasic examination technique is mandatory for contrast-enhanced cross-sectional imaging. PET/CT with somatostatin analogs should be used as the subsequent method. [ABSTRACT FROM AUTHOR]

Abstract Alzheimer's disease (AD) is a common neurodegenerative disease. The histopathological changes in AD include amyloid β‐protein (Aβ) deposition, tau tangles, neuroinflammation, and neurodegeneration. Some of the pathological changes could be shown in vivo by positron emission tomography (PET) and magnetic resonance imaging (MRI) biomarkers, which play a key role in diagnosing AD. Fluorodeoxyglucose positron emission tomography (FDG‐PET) can reflect and predict dysfunction. Aβ‐PET is sensitive for the diagnosis of early AD but cannot distinguish the severity of AD. Tau‐PET can compensate for the deficiency of Aβ‐PET. Tau tangles are positively correlated with the severity of AD and associated with cognitive impairment. Probes targeting neuroinflammation in AD have been developed, but further study is needed to validate their effectiveness. Conventional MRI performs high tissue contrast that can show structural changes and has been routinely applied in clinical practice, such as in the evaluation of cerebral atrophy. Advanced MRI sequences (such as diffusion tensor imaging, arterial spin labeling, magnetic resonance spectroscopy, blood oxygenation level dependent, and quantitative susceptibility mapping) can provide additional information beyond structure that includes brain microstructure, blood perfusion, metabolite concentration, brain activity, connections and networks between brain regions, iron deposition, etc. Integrated PET and MRI may improve the diagnostic efficiency of AD.

Background: Stage I lung adenocarcinoma is a heterogeneous group. Previous studies have shown the prognostic evaluation value of PET/CT in this cohort; however, few studies focused on stage I invasive adenocarcinoma manifesting as solid nodules. This study aimed to evaluate the recurrence risk for patients with stage I invasive lung adenocarcinoma manifesting as solid nodules based on 18F-FDG PET/CT, CT imaging signs, and clinicopathological parameters. Methods: We retrospectively enrolled 230 patients who underwent 18F-FDG PET/CT examination between January 2013 and July 2019. Metabolic parameters: maximum standard uptake value (SUVmax), mean standard uptake value, tumor metabolic volume (MTV), and total tumor glucose digestion were collected. Kaplan–Meier method was used to evaluate recurrence-free survival (RFS), and the multivariate Cox proportional hazards model was used to determine the independent risk factors associated with RFS. The time-dependent receiver operating characteristic curve (ROC) method was used to calculate the optimal cutoff value of metabolic parameters. Results: The 5-year RFS rate for all patients was 71.7%. Multivariate Cox analysis revealed that the International Association for the Study of Lung Cancer Pathology Committee (IASLC) pathologic grade 3 [Hazard ratio (HR), 3.96; 95% Confidence interval (CI), 1.11–14.09], the presence of cavity sign (HR 5.38; 95% CI 2.23–12.96), SUVmax (HR 1.23; 95% CI 1.13–1.33), and MTV (HR 1.05; 95% CI 1.01–1.08) were potential independent prognostic factors for RFS. Patients with IASLC grade 3, the presence of cavity sign, SUVmax > 3.9, or MTV > 5.4 cm3 were classified as high risk, while others were classified as low risk. There was a significant difference in RFS between the high-risk and low-risk groups (HR 6.04; 95% CI 2.17–16.82, P < 0.001), and the 5-year RFS rate was 94.1% for the low-risk group and 61.3% for the high-risk group. Conclusions: We successfully evaluate the recurrence risk of patients with stage I invasive adenocarcinoma manifesting as solid nodules for the first time. The 5-year RFS rate in the high-risk group was significantly lower than in the low-risk group (61.3% vs. 94.1%). Our study may aid in optimizing therapeutic strategies and improving survival benefits for those patients. [ABSTRACT FROM AUTHOR]

In the last decade, two new radionuclide-based therapies, 223Radichloride and radioligand therapy (RLT) targeting prostate-specific membrane antigen (PSMA), have been approved by the regulatory authorities for the management of castrate-resistant prostate cancer (PCa). The basic principles of PCa molecular imaging are illustrated, with a particular attention to the combined use of diagnosis and therapy in a unique approach (the so-called theranostics) for response prediction and assessment in patients submitted to 223Radichloride or PSMA targeted therapies. In this perspective, the potential of radiomics, an emerging discipline based on the extraction of quantitative features from medical images, is covered. Theranostic metabolic and molecular probes have been successfully applied to predict and monitor response to radionuclide-based therapies. In particular, both 99mTc-MDP and 18F-NaF resulted useful tools for personalized dosimetry and prognostic stratification before 223Ra-therapy, while PSMA-ligands, alone or in combination with 18F-FDG, provided valuable information to select patients who are more likely to benefit from RLT and getting information on PCa grade of differentiation and aggressiveness. In spite of its high potential, PET-radiomics for PCa is still at an embryonic phase and needs further validation. [ABSTRACT FROM AUTHOR]

Despite significant advances in glioma diagnosis and treatment, overall outcomes remain suboptimal. Exploring novel therapeutic avenues show promise in advancing the field. Theranostics, an evolving discipline integrating diagnosis and therapy, emerges as a particularly auspicious approach. However, an unmet need exists for glioma-associated biomarkers as theranostic targets. Immuno-positron emission tomography (Immuno-PET), a pioneering method uniting PET diagnostic precision with antibody specificity, holds potential for identifying cancer-associated biomarkers. This review aims to provide an updated overview of immuno-PET applications in gliomas. Notably, [44Sc]-CHX-A″-DTPA-Cetuximab-Fab targeting Epidermal Growth Factor Receptor (EGFR) has displayed promise in glioma xenografts, enabling potential imaging at 4 h post-injection. Similarly, [89Zr]-bevacizumab targeting vascular endothelial growth factor (VEGF) yielded encouraging results in preclinical models and a pioneering clinical trial for pediatric patients with diffuse intrinsic pontine glioma (DIPG). Several cell differentiation markers, including CD146, indicative of tumor aggressiveness, and CD11b, reflecting tumor-associated myeloid cells (TAMCs), proved effective targets for immuno-PET. Additionally, immuno-PET directed at prostate-specific antigen (PSMA) demonstrated efficacy in imaging glioma-associated neovasculature. While holding promise for precise diagnosis and treatment guidance, challenges persist in achieving target specificity and selecting suitable radionuclides. Further studies are imperative to advance the field and bridge a translational gap from bench to bedside.

Assess the diagnostic value of 18-F FDG PET/CT in cardiac implantable electronic devices (CIED) infections in facilitating diagnostic process and optimizing decision-making process.Study group (n = 21) patients with initial suspected diagnosis of CIED-related infection or fever of unknown origin and patients referred for device removal due to infection. Control group (n = 13) patients with implanted CIED, who underwent PET/CT due to other non-infectious indications and had no data for infectious process in follow-up.PET/CT scan showed pocket infection in 12 patients (including 1 in whom infection was not finally diagnosed-the examination was performed early after the implantation procedure-1.5 months), increased tracer uptake in intravascular lead part in 3 patients, and increased uptake in intracardiac part in 5 patients.We found that sensitivity, specificity, positive predictive value, and negative predictive value of the diagnosis made by PET/CT in generator pocket infection was 91.7%, 70%, 78.6%, 87.5% and in lead-dependent intracardiac infection 100%, 47.1%, 35.7%, 100% respectively. PET/CT scan enabled reclassification of diagnosis from possible to definite CIED-related infection in 6 out of 9 patients, and to excluded in 3 out of 9.Establishing diagnosis of device related infections may be challenging due to non-specific symptoms. Incorporation of PET/CT scan in the diagnostic schema can improve accuracy and timing of the diagnosis and help to assess the extent of infection. PET/CT is more useful in local than systemic infectious process related to cardiac implanted electrotherapy device.Trial registration Consent of the bioethics committee nr IK-NP.-0021-85/1465/14. Registration in the www.clinicaltrials.gov database: NCT02196753. [ABSTRACT FROM AUTHOR]

Prostate-specific membrane antigen (PSMA) has emerged as a highly relevant target for prostate cancer (PC) diagnosis and therapy. PSMA inhibitors targeting PSMA-enzymatic domain have been successfully labeled with radionuclides emitting positrons or gamma-photons, thus obtaining tracers suitable for imaging with positron emission computed tomography (PET/CT) or single-photon emission tomography (SPECT). The different approaches for obtaining PSMA-ligands labeled with gamma-emitting nuclides (99mTc or111In) are reviewed. Furthermore, the applications of 99mTc/111In-PSMA SPECT for the imaging of PC patients in different clinical settings (staging or biochemical recurrence) are covered. Lastly, the employment of PSMA-targeted SPECT tracers for radioguided surgery (RGS) during primary or salvage lymphadenectomy is discussed. RGS provided satisfying preliminary results in both primary and salvage lymphadenectomy, allowing to discriminate between pathological and non-pathological nodes with high accuracy, although prospective studies with larger cohorts are needed to further validate this surgical approach. The potential of PSMA-targeted SPECT/CT has not been fully explored yet, but it might represent a relatively cost-effective alternative to PSMA PET/CT in limited resource environments. In this perspective, the implementation of novel SPECT technologies or algorithms, such as semiconductor-ionization detectors or resolution recovery reconstruction, will be topic of future investigation. [ABSTRACT FROM AUTHOR]

Neurodegenerative diseases (NDs), including chronic disease such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis, and acute diseases like traumatic brain injury and ischemic stroke are characterized by progressive degeneration, brain tissue damage and loss of neurons, accompanied by behavioral and cognitive dysfunctions. So far, there are no complete cures for NDs; thus, early and timely diagnoses are essential and beneficial to patients' treatment. Magnetic resonance imaging (MRI) has become one of the advanced medical imaging techniques widely used in the clinical examination of NDs due to its non-invasive diagnostic value. In this review, research published in English in current decade from PubMed electronic database on the use of MRI to detect specific biomarkers of NDs was collected, summarized, and discussed, which provides valuable suggestions for the early diagnosis, prevention, and treatment of NDs in the clinic. [ABSTRACT FROM AUTHOR]

In the present study, we aimed to investigate the relationship between metabolic parameters of 18F-fluorodeoxyglucose positron emission computed tomography (18F-FDG PET/CT) and the expression of programmed death ligand-1 (PD-L1), as well as the prognostic value of PD-L1, in patients with surgically resected non-small-cell lung cancer (NSCLC). A total of 169 NSCLC patients who received preoperative 18F-FDG PET were retrospectively enrolled in the present study. The correlation between PD-L1 and patient characteristics was evaluated. Based on the expression of PD-L1 and metabolic parameters, patients were classified into low-, medium-, or high-risk groups. The maximum standardized uptake value (SUV max) and total lesion glycolysis (TLG) were significantly higher in NSCLC patients with high PD-L1 expression compared with the low expression group (P < 0.001 for all). Multivariate analysis revealed that pleural invasion (P < 0.001) and SUV max (P < 0.001) were independent predictors of PD-L1 expression. Survival analysis showed that tumor stage (P = 0.004) and pleural invasion (P = 0.007) were independent prognostic indicators of progression-free survival (PFS). Tumor stage (P = 0.001), TLG (P = 0.039), and PD-L1 expression (P = 0.001) were independent prognostic indicators of overall survival (OS). Patients of the high-risk group with high PD-L1 expression and high TLG had a poor prognosis compared with the low-risk group (P < 0.05) and medium-risk group (P < 0.05). In NSCLC patients, the SUV max of 18F-FDG PET/CT was a predictor of PD-L1 expression. The expression of PD-L1 and TLG were independent prognostic factors of OS. The risk stratification standard based on the PD-L1 expression and TLG provided valuable insights into the development of personalized treatment and follow-up. Registration number:ChiCTR2100051554. • SUV max was a predictor of PD-L1 expression in NSCLC patients. • PD-L1 expression and TLG were associated with prognosis. • Risk stratification standard provided valuable insights into the development of personalized treatment. [ABSTRACT FROM AUTHOR]

The differentiation of giant perivascular spaces is the complicated task due to its rare occurrence and multiple differential series. Cystic neoplasms, parasitic cysts, and lacunar strokes are need to be excluded. Knowing and ability to recognize pathognomonic radiological features can help to prevent excessive diagnostics and make the correct diagnose quickly. The article presents a clinical case of a rare and difficulty diagnosing variant of giant perivascular spaces.

The purpose is to present a modern data on the possibilities of positron emission computed tomography combined with computed tomography (PET/CT) in the diagnosis, staging and monitoring of prostate cancer (PC).Material and Methods. A search and analysis of the largest domestic and English-language databases (Elibrary, PubMed, Elsevier, etc.) on this problem was carried out. 37 sources were found devoted to studying the results of clinical trials of the diagnostic capabilities of PET/CT with various radiopharmaceuticals.Results. The presented data on the possibilities of PET/CT with various radiopharmaceuticals in the diagnosis of primary prostate cancer, imaging of lymphogenous and distant metastases, as well as in assessing the effectiveness of treatment.Conclusion. This review of the literature showed that the use of PET/CT in prostate cancer largely depends on the chosen radiopharmaceutical. Moreover, it is PET/CT with PSMA-based radiopharmaceuticals that is the most promising method for examining patients with prostate cancer and can be recommended as an additional study in cases where other methods of radiation diagnostics do not give an unambiguous answer. The development of new and improving the already used radiopharmaceuticals, which will increase the sensitivity, specificity and accuracy of the diagnosis, staging, monitoring and prognosis of treatment of prostate cancer, remains relevant.

Background. The treatment outcomes for non-small cell lung cancer (NSCLC) depend on the tumor stage and treatment strategy. The imaging techniques play a significant role in the diagnosis, staging and choice of appropriate treatment for NSCLC.Purpose of the study: сomparison of the diagnostic capabilities of magnetic resonance imaging (MR) and positron emission computed tomography to select the optimal approaches to early detection of spinal and pelvic bone metastases.Material and Methods. The treatment outcomes were analyzed in 71 patients with NSCLC. Spinal and pelvic bone metastases were detected in 24 patients using magnetic resonance imaging (MRI) and positron emission computed tomography (PET/CT). Multiple bone lesions were the most common. A total of 69 metastatic lesions were identified. To compare the capabilities of diagnostic techniques, all patients underwent PET/CT with 18F-FDG, and MRI of the spine and pelvic bones using diffused-weighted images (DWI). Statistical data processing included the calculation of the sensitivity, specificity and diagnostic accuracy of the above techniques.Conclusion. The comparative analysis of the capabilities of modern high-tech diagnostic techniques (PET/CT with 18F-FDG and MRI of the spine and pelvic bones with DWI) in early detection of bone metastases in patients with NSCLC, PET/CT with 18F-FDG showed the greatest diagnostic value. However, taking into account the high sensitivity and specificity of MRI with DVI in detection of bone metastases and limited availability of PET/CT for patients, MRI with DVI is recommended to exclude bone metastases.

Objective: We aimed to evaluate the feasibility of resting myocardial blood flow (rMBF), quantified with dynamic 13 N-Ammonia (NH3) PET, for identifying myocardial viability and predicting improvement of left ventricular ejection fraction (LVEF) after coronary artery bypass grafting (CABG). Methods: Ninety-three patients with coronary artery disease (CAD) and chronic LVEF < 45%, scheduled for CABG, had dynamic 13NH3 PET and 18F-FDG PET imaging. The perfusion/metabolism polar maps were categorized in four patterns: normal (N), mismatch (M1), match (M2) and reverse mismatch (RM). The value of rMBF for identifying viable myocardium (M1, RM) and post CABG improvement of LVEF≥8% was analyzed by receiver operating characteristic (ROC) curves. Correlations of rMBF in segments to ΔLVEF post CABG were verified. Results: Mean rMBFs were significantly different (N=0.60±0.14; M1=0.44±0.07, M2=0.34±0.08, RM=0.53±0.09 ml/min/g, P<0.001). The optimal rMBF cutoff to identify viable myocardium was 0.42 ml/min/g (sensitivity=88.3%, specificity=82.0%) and 0.43 ml/min/g for predicting improvement of LVEF ≥8% (74.6%, 80.0%). The extent and rMBF of combined M1/RM demonstrated a moderate to high correlation to improved LVEF (r=0.78, 0.71, P<0.001). Conclusion: Resting MBF, derived by dynamic 13NH3 PET, may be positioned as a supplement to 18F-FDG PET imaging for assessing the presence of viable myocardium and predicting potential improvement of LVEF after CABG. [ABSTRACT FROM AUTHOR]

Introduction: Head and neck squamous cell carcinoma is the seventh most common malignant tumor. The advances in treatment have improved the global survival rates in the past years, although the prognosis is still grave. Objective: The aim of the present study is to evaluate the correlation between positron emission computed tomography and computed tomography at the time of staging a previously untreated head and neck squamous cell carcinoma, and to determine which of the two imaging techniques gives us more information at the time of initial diagnosis. Methods: Data from all patients diagnosed in our hospital of head and neck squamous cell carcinoma by a biopsy of any location or unknown primary tumor was collected, between January 2012 and July 2017. In all cases, computed tomography and positron emission computed tomography were performed with a maximum of 30 days difference between them and patients had not received any prior treatment to staging. The stage given to each case was compared based solely on the physical examination, only on the computed tomography/positron emission computed tomography, with respect to the stage given by the tumor board, observing the concordance obtained through Cramer's V statistical test. Results: We performed a comparative analysis obtaining a correlation of 0.729 between the stage given by the tumor board and the one assigned based on the physical examination without imaging techniques. When only using computed tomography as an imaging method, the correlation was 0.848, whereas with only the use of positron emission computed tomography it was estimated at 0.957. When comparing the statistical association between staging using exclusively one of the two imaging techniques, correlation was 0.855. Conclusion: Positron emission computed tomography is useful for the diagnosis of head and neck squamous cell carcinoma, improving the patient's staging especially when detecting cervical and distant metastases. Therefore, we consider that the use of positron emission computed tomography for the staging of patients with head and neck squamous cell carcinoma is a diagnostic test to be considered.

Myxofibrosarcoma (MFS) is a rare soft tissue sarcoma that originates in the mesenchymal tissue and occurs mainly in the limbs of elderly patients. Herein, we present the case of a 64-year-old woman who underwent extensive left vulvar resection and bilateral lymphadenectomy for vulvar squamous cell carcinoma 6 months previously. A mass was found again at the original surgical site of the left groin 3 months prior, and its size had increased significantly in the past 1 month, with ulceration and pus. Magnetic resonance imaging (MRI) showed a 10-cm mass in the left groin area; fluoro18-labeled deoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) showed a marked increase in mass metabolism in the left groin area, which was highly suspected to be a recurrence of squamous cell carcinoma. Subsequently, the patient underwent surgery and the postoperative pathology and immunohistochemistry confirmed MFS. In conclusion, MFS has rarely been reported to arise from the surgical site of squamous cell carcinoma. Our case study demonstrates that MFS should be included in the differential diagnosis of superficial masses in patients with a prior surgical history who present with a soft tissue mass at the surgical site, especially for recently developed rapidly increasing masses. This study aimed to systematically review the clinical features, diagnosis, differential diagnosis, treatment, and prognosis of this disease based on our case and related published literature and to provide clinicians with a broader perspective on the differential diagnosis of soft tissue tumors. [ABSTRACT FROM AUTHOR]

Primary epithelioid hemangioendothelioma of the spine is the extremely rare malignant vascular neoplasm with an unpredictable outcome. A case of epithelioid hemangioendothelioma with multiple lytic lesions of thoracolumbar spine and other bones in a 29-year-old male patient is reported. A review of the published data regarding this rare neoplasm is also presented. The features of epithelioid hemangioendothelioma include the occurrence in the young male patient, multiple osteolytic lesions with thin sclerotic rim and hypermetabolic activities. However, its imaging features are not specific. Positron emission tomography/computed tomography is essential for identification of the lesions and subsequent follow-up for treatment.

Myxofibrosarcoma (MFS) is a rare soft tissue sarcoma that originates in the mesenchymal tissue and occurs mainly in the limbs of elderly patients. Herein, we present the case of a 64-year-old woman who underwent extensive left vulvar resection and bilateral lymphadenectomy for vulvar squamous cell carcinoma 6 months previously. A mass was found again at the original surgical site of the left groin 3 months prior, and its size had increased significantly in the past 1 month, with ulceration and pus. Magnetic resonance imaging (MRI) showed a 10-cm mass in the left groin area; fluoro18-labeled deoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) showed a marked increase in mass metabolism in the left groin area, which was highly suspected to be a recurrence of squamous cell carcinoma. Subsequently, the patient underwent surgery and the postoperative pathology and immunohistochemistry confirmed MFS. In conclusion, MFS has rarely been reported to arise from the surgical site of squamous cell carcinoma. Our case study demonstrates that MFS should be included in the differential diagnosis of superficial masses in patients with a prior surgical history who present with a soft tissue mass at the surgical site, especially for recently developed rapidly increasing masses. This study aimed to systematically review the clinical features, diagnosis, differential diagnosis, treatment, and prognosis of this disease based on our case and related published literature and to provide clinicians with a broader perspective on the differential diagnosis of soft tissue tumors.

The aim of this study was to evaluate the preclinical efficacy of [ 89 Zr]Zr-DFO-Ab253 as a novel positron emission tomography (PET) tracer for CD146-positive malignant melanoma imaging. Considering the high expression of CD146 in malignant melanoma, this study investigated the effect of different CD146 expression levels on the tumor uptake of [ 89 Zr]Zr-DFO-Ab253. CD146 selectivity was investigated by using the CD146-positive human melanoma cell A375 and the CD146-negative human alveolar epithelial cell A549. The cell uptake of [ 89 Zr]Zr-DFO-Ab253 tracers was investigated, and receptor-binding affinities were measured by radioactive enzyme-linked immunosorbent assay. Biodistribution studies and micro-PET imaging of the radiotracers were performed on mice bearing A375 and A549 xenografts under baseline and blocking conditions. An immunohistochemical test was performed using A375 and A549 tissue sections for CD146 expression level analysis. [ 89 Zr]Zr-DFO-Ab253 was obtained with a high radiochemical yield (87.86 ± 4.66%) and a satisfactory radiochemical purity (>98.0%). The specificity and affinity of [ 89 Zr]Zr-DFO-Ab253 were confirmed in melanoma A375 cells and in vivo PET imaging of A375 tumor models. [ 89 Zr]Zr-DFO-IgG and A549 lung tumors were prepared as control radiotracers and negative models to verify the specificity of [ 89 Zr]Zr-DFO-Ab253 on CD146. [ 89 Zr]Zr-DFO-Ab253 has a K d of 4.01 ± 0.50 nM. PET imaging and biodistribution showed a higher uptake of [ 89 Zr]Zr-DFO-Ab253 in A375 melanomas than that in A549 tumors (42.1 ± 4.04% vs 7.87 ± 1.30% ID/g at 120 h, P < 0.05). A low tumor uptake of [ 89 Zr]Zr-DFO-IgG was observed with uptakes of 1.91 ± 0.41 and 2.80 ± 0.14 ID%/g when blocked at 120 h. The radiation-absorbed dose was calculated to be 0.13 mSv/MBq. This study demonstrates the synthesis and preclinical evaluation of [ 89 Zr]Zr-DFO-Ab253 and indicates that the novel tracer has promising applications in malignant melanoma-specific PET imaging because of its high uptake and long-time retention in malignant melanoma. It also provides feasibility for the development of integrated molecular probes for diagnosis and treatment based on the CD146 target.

Nasopharyngeal carcinoma (NPC) is a malignant tumor of the head and neck. The primary clinical manifestations are nasal congestion, blood-stained nasal discharge, headache, and hearing loss. It occurs frequently in Southeast Asia, North Africa, and especially in southern China. Radiotherapy is the main treatment, and currently, imaging examinations used for the diagnosis, treatment, and prognosis of NPC include computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET)-CT, and PET-MRI. These methods play an important role in target delineation, radiotherapy planning design, dose evaluation, and outcome prediction. However, the anatomical and metabolic information obtained at the macro level of images may not meet the increasing accuracy required for radiotherapy. As a technology used for mining deep image information, radiomics can provide further information for the diagnosis and treatment of NPC and promote individualized precision radiotherapy in the future. This paper reviews the application of radiomics in the diagnosis and treatment of nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is a malignant tumor of the head and neck. The primary clinical manifestations are nasal congestion, blood-stained nasal discharge, headache, and hearing loss. It occurs frequently in Southeast Asia, North Africa, and especially in southern China. Radiotherapy is the main treatment, and currently, imaging examinations used for the diagnosis, treatment, and prognosis of NPC include computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET)-CT, and PET-MRI. These methods play an important role in target delineation, radiotherapy planning design, dose evaluation, and outcome prediction. However, the anatomical and metabolic information obtained at the macro level of images may not meet the increasing accuracy required for radiotherapy. As a technology used for mining deep image information, radiomics can provide further information for the diagnosis and treatment of NPC and promote individualized precision radiotherapy in the future. This paper reviews the application of radiomics in the diagnosis and treatment of nasopharyngeal carcinoma. [ABSTRACT FROM AUTHOR]

PD-1/PD-L1 immune checkpoint therapy has become another important treatment for several refractory and recurrent tumors besides radiotherapy and chemotherapy; however, only some patients can benefit from it. PD-1/PD-L1 targeted radionuclide molecular probe imaging can detect the PD-1/PD-L1 expression in whole body including tumors and other tissues noninvasively, timely and repeatedly, which will be more convenient for screening the patients benefiting from the immune-therapy, the efficacy evaluation and dynamic monitoring of the changes of PD-1/PD-L1 expression during treatment, providing a strong basis for the adjustment of treatment plan. This paper will review the recent progress of PD-1/PD-L1 targeted molecular probes, in order to provide reference for clinical application and further research of tumor immunotherapy.

Objective To evaluate the relation between the expression of programmed cell death protein receptor-1 (PD-L1) and 18F-deoxyglucose (18F-FDG) uptake in lung adenocarcinoma. Methods We retrospectively analyzed the clinical data of 102 patients with pathologically-confirmed lung adenocarcinoma who underwent 18F-FDG PET/CT examinations before treatment and immunohistochemical examination after treatment to detect the expression of PD-L1. The relation between the maximum standard uptake of 18F-FDG(SUVmax) and the expression of PD-L1 was analyzed. Results PD-L1 positive were detected in 50 patients (49%), the SUVmax was significantly higher in PD-L1 positive patients than that in the negative patients (6.59±5.03 vs. 2.89±4.65, P=0.0001). For the prediction of PD-L1 expression by SUVmax, the area under the ROC curve was 0.801, P=0.0001; when the cut off value was 1.70, the maximum value of Jordan index was 0.522. Conclusion 18F-FDG uptake is associated with PD-L1 expression in primary lung adenocarcinoma, and the patients with high SUVmax are more likely to harbor PD-L1 expression.

Objective To investigate the relation between 18F-FDG PET/CT metabolic parameters and the clinicopathological characteristics of colorectal cancer (CRC) patients. Methods We included 358 CRC patients who met the admission criteria. 18F-FDG PET/CT scans were performed before any treatment. Maximum standard uptake, average standard uptake, tumor metabolic volume (MTV) and total glycolysis (TLG) of the primary lesion of CRC were measured and calculated. The correlation of metabolic parameters with lesion location, pathological profile and TNM staging were investigated through Mann-Whitney U test and Kruskal-Wallis test. Results The MTV and TLG values in the primary foci of colon cancer were the highest, followed by sigmoid cancer and the lowest in rectal cancer, with statistically significant differences between the groups (P < 0.001). SUVmax values of poorly/poorly-moderately differentiated colorectal cancer were higher than those of moderately/well differentiated colorectal cancer (P=0.028). MTV values of primary mucinous adenocarcinoma were higher than those of primary adenocarcinoma (P=0.023). MTV and TLG values were higher in T4 lesions than those in T2-3 lesions (P=0.0001, P=0.007); SUVmax and SUVmean values of sigmoid carcinoma with distant metastasis were lower than those without distant metastasis(P=0.015, P=0.011). Conclusion The metabolic parameters of CRC are correlated with the lesion location, pathological features and TNM staging, which could partly reflect the pathological characteristics and heterogeneity of CRC.

The purpose of the study was to provide up-to-date data on the efficacy of positron emission computed tomography (PET) for the diagnosis, assessment of tumor extension and monitoring of colorectal cancer.Material and Methods. The Medline and Pubmed databases were used for searching for publications devoted to clinical trials of diagnostic value of PET with 18F-Ftordesoxyglucose (PET with 18F-FDG).Results. Data on the value of PET with 18F-FDG in visualization of the primary tumor, detection of lymph node and distant metastases and assessment of the treatment response in patients with colorectal cancer were presented.Conclusion. PET with 18F-FDG was shown to be a promising imaging method for colorectal cancer. It is the most sensitive method in the detection of liver metastases. 18F-FDG PET is particularly superior to CT and MET in the ability to assess tumor response to treatment and predict early tumor response to therapy. The development of new radiopharmaceuticals for the diagnosis, staging, monitoring and prediction of colorectal cancer is of great importance.

It was to study the adoption of positron emission computed tomography (PET-CT) based on the convolutional neural networks (CNN) model in the monitoring of postoperative pneumonia virus infection in patients with non-small cell lung cancer (NSCLC). 120 patients with NSCLC were set as the research object. CNN model was constructed and applied to PET-CT images to identify lesions and screen tumor markers for detection. Then, the patients were randomly divided into group A (CT), group B (PET-CT), group C (PET-CT based on artificial neural network model), and group D (PET-CT diagnosis based on CNN model), 30 cases in each group, and infection surveillance was conducted. The result showed that the accuracy (Acc), sensitivity (Sen), and specificity (Spe) of PET-CT image recognition based on the CNN model were 99.31%, 100%, and 98.31%, respectively. The proportion of serum neutrophils, white blood cell count, and PCT content in group D three days after operation were significantly lower than those in groups B, C, and A (P

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Only a few effective methods can detect internal defects and monitor the internal state of complex structural parts. On the basis of the principle of PET (positron emission computed tomography), a new measurement method, using γ photon to detect defects of an inner surface, is proposed. This method has the characteristics of strong penetration, anti-corrosion and anti-interference. With the aim of improving detection accuracy and imaging speed, this study also proposes image reconstruction algorithms, combining the classic FBP (filtered back projection) with MLEM (maximum likelihood expectation Maximization) algorithm. The proposed scheme can reduce the number of iterations required, when imaging, to achieve the same image quality. According to the operational demands of FPGAs (field-programmable gate array), a BPML (back projection maximum likelihood) algorithm is adapted to the structural characteristics of an FPGA, which makes it feasible to test the proposed algorithms therein. Furthermore, edge detection and defect recognition are conducted after reconstructing the inner image. The effectiveness and superiority of the algorithm are verified, and the performance of the FPGA is evaluated by the experiments.

Abstract Radical resection is the most effective method for malignant tumor treatments. However, conventional imaging cannot fully satisfy the clinical needs of surgical navigation. This study presents a novel triple‐modality positron emission tomography (PET)–Cerenkov radiation energy transfer (CRET)–confocal laser endomicroscopy (CLE) imaging strategy for intraoperative tumor imaging and surgical navigation. Using clinical radiopharmaceuticals and fluorescein sodium (FS), this strategy can accurately detect the tumor and guide the tumor surgery. The FS emission property under Cerenkov radiation excitation is investigated using 2‐deoxy‐2‐18F‐fluoroglucose and 11C‐choline. Performances of the PET–CRET–CLE imaging and the CRET–CLE image‐guided surgery are evaluated on mouse models. The CRET signal at 8 mm depth is stronger than the Cerenkov luminescence at 1 mm depth in phantoms. In vivo experiments indicate that 0.5 mL kg−1 of 10% FS generates the strongest CRET signal, which can be observed immediately after FS injection. A surgical navigation study shows that the tumors are precisely detected and resected using intraoperative CRET–CLE. In summary, a PET–CRET–CLE triple‐modality imaging strategy is developed. This strategy can detect the tumors and precisely guide the tumor resection using clinical pharmaceuticals. This triple‐modality imaging shows high potential in surgical navigation research and clinical translation.

Background: our aim was to assess the diagnostic performance and clinical impact of 18F-FDG PET/CT in patients with differentiated thyroid carcinoma (DTC), previously treated with surgery and radioiodine therapy (RAI). Methods: patients subjected to 18F-FDG PET/CT for suspected DTC recurrence in three Italian nuclear medicine units were evaluated. Two different clinical settings were identified: clinical setting 1 included patients (n = 40) that were enrolled according to the American Thyroid Association guidelines (i.e., negative 1311-WBS and Tg level > 10 ng/mL); and clinical setting 2, that encompassed subjects (n = 26) with serum Tg ≤ 10 ng/mL but morphological findings suspected of relapse. PET/CT’s impact was scored as significant if it provided an indication for surgery, or led to a novel therapeutic decision. Results: In total, 51/66 patients (77.3%) were 18F-FDG positive, while 15 (22.7%) were negative. PET/CT showed an overall sensitivity and specificity of 84.4% and 75%, respectively. Sensitivity was higher in clinical setting 1 (89.1%) as compared to clinical setting 2 (76.1%), although this difference was not statistically significant (p = 0.83). PET/CT influenced clinical management in 28 cases (42.4%), without a significant difference between the 2 groups of patients (p = 0.6). Conclusions: our preliminary data, although limited by the retrospective nature of the study and possible selection bias, suggest that 18F-FDG PET/CT may be utilized for the detection of DTC recurrence in different clinical settings, with a meaningful impact on clinical management.

Objective To assess the value of 18F-fluoromisonidazole (FMISO) positron emission tomography (PET) for detecting liver metastasis from human colorectal cancer in mice. Methods Wound healing assays were performed to examine the ability of cell migration in vitro. I8F-FM1S0 uptake in CRC cell lines was measured by cellular uptake assay. I8F-FMIS0 micro-PET imaging of liver metastasis in mice with human colorectal cancer was performed. The tumor-to-liver ratio of maximum standard uptake values (SUVmax)was calculated. The correlation between the 18F-FMISO SLVmax ratio, number of liver metastases, hypoxia-induced HIF-la, and serum starvation-induced GLUT-1 was evaluated using Pearson correlation analysis. Results Compared with IIT29 and HCT116, LoVo -CLM mice had significantly higher liver metastasis ratio and shorter median survival time. LoVo cells exhibited stronger migration capacity and higher radiotracer uptake compared with HT29 and HCT116 in in vitro. Moreover, 18F-FMISO SUVmax0 ratio was significantly higher in both LoVo-CLM model and LoVo-bearing tumor model compared to models established using HT29 and HCT116. Linear regression analysis showed significant correlation between 18F-FMISO SUVmax ratio of CLM-mice and number of liver metastases larger than 0.5 cm (r=0.6408, P=0.0013), as well as between 18F-FMISO SUVmix ratio and HIF-la (r=0.8145, P= 0.0075) or GLUT-1 (r=0.8252, P=0.0062) expression in tumor-bearing tissues. Conclusion 18F-FMISO PET imaging parameter of SUVma ratio provides tumor biological information and may be a marker for predicting liver metastasis from colorectal cancer. [ABSTRACT FROM AUTHOR]