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1.
Int J Mol Sci ; 25(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-39000301

RESUMO

PET/CT using radiolabeled fibroblast activation protein inhibitors (FAPIs) is a promising diagnostic tool in oncology, especially when non-increased and/or physiologically high [18F]FDG uptake (as in liver parenchyma) is observed. We aimed to review the role of PET/CT using radiolabeled FAPIs in primary and/or metastatic liver lesions, and to compare their performances with more "conventional" radiopharmaceuticals. A search algorithm based on the terms "FAPI" AND ("hepatic" OR "liver") was applied, with the last update on 1st January 2024. Out of 177 articles retrieved, 76 studies reporting on the diagnostic application of radiolabeled FAPI PET/CT in at least one patient harboring primary or metastatic liver lesion(s) were fully analyzed. Although there was some heterogeneity in clinical conditions and/or study methodology, PET/CT with radiolabeled FAPIs showed an excellent performance in common primary liver malignancies (hepatocarcinoma, intrahepatic cholangiocarcinoma) and liver metastases (mostly from the gastrointestinal tract and lungs). A higher tumor-to-background ratio for FAPIs than for [18F]FDG was found in primary and metastatic liver lesions, due to lower background activity. Despite limited clinical evidence, radiolabeled FAPIs may be used to assess the suitability and effectiveness of FAPI-derived therapeutic agents such as [177Lu]Lu-FAPI. However, future prospective research on a wider population is needed to confirm the excellent performance.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Hepáticas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/metabolismo , Compostos Radiofarmacêuticos/química , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Endopeptidases/metabolismo , Gelatinases/metabolismo , Gelatinases/antagonistas & inibidores
2.
Pancreas ; 53(7): e560-e565, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38986077

RESUMO

OBJECTIVE: We investigated metabolic tumor volume (MTV) and total lesion glycolysis (TLG) on pre-treatment FDG-PET as prognostic markers for survival in patients with metastatic neuroendocrine neoplasms (NENs) receiving peptide receptor radionuclide therapy (PRRT). METHODS: A retrospective review of patients with metastatic NENs receiving PRRT was undertaken. Pre-treatment FDG-PET images were analyzed and variables collected included MTV and TLG (dichotomized by median into high vs low). Main Outcomes were overall survival (OS) and progression-free survival (PFS) by MTV and TLG (high vs low). RESULTS: One hundred five patients were included. Median age was 64 years (50% male). Main primary NEN sites were small bowel (43.8%) and pancreas (40.0%). Median MTV was 3.8 mL and median TLG was 19.9. Dichotomization formed identical cohorts regardless of whether MTV or TLG were used. Median OS was 72 months; OS did not differ based on MTV/TLG high versus low (47.4 months vs not reached; hazard ratio, 0.43; 95% confidence interval [CI], 0.18-1.04; P = 0.0594). Median PFS was 30.4 months; PFS differed based on MTV/TLG high versus low (21.6 months vs 45.7 months; hazard ratio, 0.35; 95% CI, 0.19-0.64; P = 0.007). CONCLUSIONS: Low MTV/TLG on pre-treatment FDG-PET was associated with longer PFS in metastatic NEN patients receiving PRRT.


Assuntos
Fluordesoxiglucose F18 , Tumores Neuroendócrinos , Octreotida , Compostos Organometálicos , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Carga Tumoral , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/radioterapia , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/mortalidade , Estudos Retrospectivos , Idoso , Octreotida/análogos & derivados , Octreotida/uso terapêutico , Tomografia por Emissão de Pósitrons/métodos , Prognóstico , Compostos Organometálicos/uso terapêutico , Adulto , Receptores de Peptídeos/metabolismo , Glicólise , Idoso de 80 Anos ou mais , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/radioterapia , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/mortalidade , Intervalo Livre de Progressão , Resultado do Tratamento
3.
Int J Mol Sci ; 25(13)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-39000586

RESUMO

Visceral adipose tissue (VAT) dysfunction has been recently recognized as a potential contributor to the development of Alzheimer's disease (AD). This study aimed to explore the relationship between VAT metabolism and cerebral glucose metabolism in patients with cognitive impairment. This cross-sectional prospective study included 54 patients who underwent 18F-fluorodeoxyglucose (18F-FDG) brain and torso positron emission tomography/computed tomography (PET/CT), and neuropsychological evaluations. VAT metabolism was measured by 18F-FDG torso PET/CT, and cerebral glucose metabolism was measured using 18F-FDG brain PET/CT. A voxel-based analysis revealed that the high-VAT-metabolism group exhibited a significantly lower cerebral glucose metabolism in AD-signature regions such as the parietal and temporal cortices. In the volume-of-interest analysis, multiple linear regression analyses with adjustment for age, sex, and white matter hyperintensity volume revealed that VAT metabolism was negatively associated with cerebral glucose metabolism in AD-signature regions. In addition, higher VAT metabolism was correlated with poorer outcomes on cognitive assessments, including the Korean Boston Naming Test, Rey Complex Figure Test immediate recall, and the Controlled Oral Word Association Test. In conclusion, our study revealed significant relationships among VAT metabolism, cerebral glucose metabolism, and cognitive function. This suggests that VAT dysfunction actively contributes to the neurodegenerative processes characteristic of AD, making VAT dysfunction targeting a novel AD therapy approach.


Assuntos
Encéfalo , Disfunção Cognitiva , Fluordesoxiglucose F18 , Glucose , Gordura Intra-Abdominal , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Masculino , Feminino , Gordura Intra-Abdominal/metabolismo , Gordura Intra-Abdominal/diagnóstico por imagem , Glucose/metabolismo , Idoso , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Fluordesoxiglucose F18/metabolismo , Estudos Transversais , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Prospectivos , Doença de Alzheimer/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Testes Neuropsicológicos
4.
Phys Med Biol ; 69(15)2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38959909

RESUMO

Objective.Head and neck (H&N) cancers are among the most prevalent types of cancer worldwide, and [18F]F-FDG PET/CT is widely used for H&N cancer management. Recently, the diffusion model has demonstrated remarkable performance in various image-generation tasks. In this work, we proposed a 3D diffusion model to accurately perform H&N tumor segmentation from 3D PET and CT volumes.Approach.The 3D diffusion model was developed considering the 3D nature of PET and CT images acquired. During the reverse process, the model utilized a 3D UNet structure and took the concatenation of 3D PET, CT, and Gaussian noise volumes as the network input to generate the tumor mask. Experiments based on the HECKTOR challenge dataset were conducted to evaluate the effectiveness of the proposed diffusion model. Several state-of-the-art techniques based on U-Net and Transformer structures were adopted as the reference methods. Benefits of employing both PET and CT as the network input, as well as further extending the diffusion model from 2D to 3D, were investigated based on various quantitative metrics and qualitative results.Main results.Results showed that the proposed 3D diffusion model could generate more accurate segmentation results compared with other methods (mean Dice of 0.739 compared to less than 0.726 for other methods). Compared to the diffusion model in 2D form, the proposed 3D model yielded superior results (mean Dice of 0.739 compared to 0.669). Our experiments also highlighted the advantage of utilizing dual-modality PET and CT data over only single-modality data for H&N tumor segmentation (with mean Dice less than 0.570).Significance.This work demonstrated the effectiveness of the proposed 3D diffusion model in generating more accurate H&N tumor segmentation masks compared to the other reference methods.


Assuntos
Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço , Imageamento Tridimensional , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Imageamento Tridimensional/métodos , Difusão
5.
Sci Rep ; 14(1): 16294, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009706

RESUMO

Radiomics analysis of [18F]-fluorodeoxyglucose ([18F]-FDG) PET images could be leveraged for personalised cancer medicine. However, the inherent sensitivity of radiomic features to intensity discretisation and voxel interpolation complicates its clinical translation. In this work, we evaluated the robustness of tumour [18F]-FDG-PET radiomic features to 174 different variations in intensity resolution or voxel size, and determined whether implementing parameter range conditions or dependency corrections could improve their robustness. Using 485 patient images spanning three cancer types: non-small cell lung cancer (NSCLC), melanoma, and lymphoma, we observed features were more sensitive to intensity discretisation than voxel interpolation, especially texture features. In most of our investigations, the majority of non-robust features could be made robust by applying parameter range conditions. Correctable features, which were generally fewer than conditionally robust, showed systematic dependence on bin configuration or voxel size that could be minimised by applying corrections based on simple mathematical equations. Melanoma images exhibited limited robustness and correctability relative to NSCLC and lymphoma. Our study provides an in-depth characterisation of the sensitivity of [18F]-FDG-PET features to image processing variations and reinforces the need for careful selection of imaging biomarkers prior to any clinical application.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Fluordesoxiglucose F18 , Processamento de Imagem Assistida por Computador , Tomografia por Emissão de Pósitrons , Humanos , Tomografia por Emissão de Pósitrons/métodos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Linfoma/diagnóstico por imagem , Linfoma/patologia , Compostos Radiofarmacêuticos , Melanoma/diagnóstico por imagem , Melanoma/patologia , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Radiômica
6.
Sci Rep ; 14(1): 16316, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009884

RESUMO

The objective of this study was to evaluate semi-quantitatively the diagnostic performance of PET/CT metabolic parameters in differentiating benign or malignant cardiac or pericardial masses. A total of forty-one patients with newly diagnosed cardiac/pericardial masses who underwent 18F-FDG PET/CT were recruited. PET/CT metabolic parameters including the maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), total lesion glycolysis (TLG), tumor metabolic volume (MTV), the maximum tumor-to-mediastinal background ratio (TMR) and the maximum tumor-to-liver background ratio (TLR) is measured or calculated to evaluate the benign or malignant nature of cardiac/pericardial masses. Compared with benign cardiac/pericardial lesions, cardiac/pericardial malignancies had higher SUVmax, SUVmean, TLG, MTV, TMR, and TLR. All these PET/CT metabolic parameters showed high diagnostic performance in semi-quantitative evaluation of benign or malignant cardiac or pericardial masses, and SUVmean and MTV had the highest diagnostic accuracy. Therefore, PET/CT metabolic parameters can semi-quantitatively evaluate the benign or malignant cardiac/pericardial masses.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Cardíacas , Pericárdio , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/metabolismo , Idoso , Pericárdio/diagnóstico por imagem , Pericárdio/metabolismo , Pericárdio/patologia , Adulto , Compostos Radiofarmacêuticos , Idoso de 80 Anos ou mais
7.
Clin Nucl Med ; 49(8): e410-e411, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38967512

RESUMO

ABSTRACT: We report a rare case of intramedullary spinal cord malakoplakia mimicking malignancy on 18F-FDG PET/CT. A 61-year-old man underwent a contrast-enhanced spinal cord MRI to evaluate 1 week of progressive left-sided weakness. Spinal cord MRI showed a 1.3-cm enhancing intramedullary cervical spinal cord mass at C5 level with cord edema. Subsequently, 18F-FDG PET/CT was performed for evaluation. The images showed a well-circumscribed hypermetabolic mass in the spinal cord; no lesions were suggestive of malignancy or metastasis. A subtotal tumor excision was performed; histopathological examination revealed malakoplakia. This emphasizes the significance of histopathological evaluation and the importance of diagnostic confirmation.


Assuntos
Fluordesoxiglucose F18 , Malacoplasia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Medula Espinal , Humanos , Masculino , Pessoa de Meia-Idade , Diagnóstico Diferencial , Neoplasias da Medula Espinal/diagnóstico por imagem , Malacoplasia/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Imagem Multimodal , Tomografia por Emissão de Pósitrons
8.
Clin Nucl Med ; 49(8): e406-e407, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38967511

RESUMO

ABSTRACT: FDG PET/CT is a well-documented imaging investigation to evaluate fever of unknown origin (FUO). Brucellosis is one of the causes of FUO, which can be missed as it requires a longer incubation period for growth on culture media. Rarely, it can involve the prostate. Here, we present a case of FUO with initial negative blood and urine cultures and no localizing signs or symptoms. 18F-FDG PET/CT revealed hypermetabolism in the prostate and seminal vesicles. A repeat blood and urine culture showed the growth of Brucella species after 5 days of incubation, and the patient responded to Brucella-directed antibiotic therapy.


Assuntos
Brucelose , Febre de Causa Desconhecida , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prostatite , Humanos , Masculino , Febre de Causa Desconhecida/diagnóstico por imagem , Prostatite/diagnóstico por imagem , Prostatite/microbiologia , Brucelose/diagnóstico por imagem , Brucelose/complicações , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
9.
Sci Rep ; 14(1): 15264, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961124

RESUMO

This study evaluated the use of F-18 fluorodeoxyglucose (FDG) PET/CT imaging to differentiate between scrub typhus and systemic lupus erythematosus (SLE) in patients presenting with lymphadenopathy. We carried out a retrospective analysis of 18 scrub typhus patients and seven SLE patients, using various imaging parameters, including lymph node size, spleen and liver lengths, the distance between the two farthest lesions (Dmax), and assessments of glucose metabolism. On FDG PET images, we measured the maximum standardized uptake value (SUVmax) of the lymph nodes, spleen, and liver and the mean standardized uptake value (SUVmean) of the liver and spleen. The Dmax values of scrub typhus patients were significantly longer than those of SLE patients, indicating that lymphadenopathy is more generalized in the patients with scrub typhus. The SUVmax values for the lymph node, spleen, and liver were also higher in patients with scrub typhus, while the SUVmean of the liver and spleen did not differ between the two groups. This study is the first to compare FDG PET/CT images between these two conditions, suggesting the potential of this imaging modality to provide critical diagnostic distinctions.


Assuntos
Fluordesoxiglucose F18 , Lúpus Eritematoso Sistêmico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tifo por Ácaros , Humanos , Tifo por Ácaros/diagnóstico por imagem , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Lúpus Eritematoso Sistêmico/complicações , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Estudos Retrospectivos , Idoso , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Baço/diagnóstico por imagem , Baço/patologia , Fígado/diagnóstico por imagem , Fígado/patologia , Fígado/metabolismo , Diagnóstico Diferencial , Compostos Radiofarmacêuticos , Adulto Jovem
10.
CNS Neurosci Ther ; 30(7): e14821, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38948940

RESUMO

AIMS: To investigate the diagnostic and predictive role of 18F-FDG PET/CT in patients with autoimmune encephalitis (AE) as a whole group. METHODS: Thrty-five patients (20 females and 15 males) with AE were recruited. A voxel-to-voxel semi-quantitative analysis based on SPM12 was used to analyze 18F-FDG PET/CT imaging data compared to healthy controls. Further comparison was made in different prognostic groups categorized by modified Rankin Scale (mRS). RESULTS: In total, 24 patients (68.6%) were tested positive neuronal antibodies in serum and/or CSF. Psychiatric symptoms and seizure attacks were major clinical symptoms. In the acute stage, 13 patients (37.1%) demonstrated abnormal brain MRI results, while 33 (94.3%) presented abnormal metabolism patterns. 18F-FDG PET/CT was more sensitive than MRI (p < 0.05). Patients with AE mainly presented mixed metabolism patterns compared to the matched controls, demonstrating hypermetabolism mainly in the cerebellum, BG, MTL, brainstem, insula, middle frontal gyrus, and relatively hypometabolism in the frontal cortex, occipital cortex, temporal gyrus, right parietal gyrus, left cingulate gyrus (p < 0.05, FWE corrected). After a median follow-up of 26 months, the multivariable analysis identified a decreased level of consciousness as an independent risk factor associated with poor outcome of AE (HR = 3.591, p = 0.016). Meanwhile, decreased metabolism of right superior frontal gyrus along with increased metabolism of the middle and upper brainstem was more evident in patients with poor outcome (p < 0.001, uncorrected). CONCLUSION: 18F-FDG PET/CT was more sensitive than MRI to detect neuroimaging abnormalities of AE. A mixed metabolic pattern, characterized by large areas of cortical hypometabolism with focal hypermetabolism was a general metabolic pattern. Decreased metabolism of right superior frontal gyrus with increased metabolism of the middle and upper brainstem may predict poor long-term prognosis of AE.


Assuntos
Encefalite , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Feminino , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Adulto , Pessoa de Meia-Idade , Encefalite/diagnóstico por imagem , Encefalite/metabolismo , Adulto Jovem , Estudos de Coortes , Valor Preditivo dos Testes , Doença de Hashimoto/diagnóstico por imagem , Doença de Hashimoto/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Adolescente , China , Compostos Radiofarmacêuticos , Idoso , Imageamento por Ressonância Magnética , População do Leste Asiático
11.
Cancer Imaging ; 24(1): 87, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970050

RESUMO

Over the past decade, several strategies have revolutionized the clinical management of patients with cutaneous melanoma (CM), including immunotherapy and targeted tyrosine kinase inhibitor (TKI)-based therapies. Indeed, immune checkpoint inhibitors (ICIs), alone or in combination, represent the standard of care for patients with advanced disease without an actionable mutation. Notably BRAF combined with MEK inhibitors represent the therapeutic standard for disease disclosing BRAF mutation. At the same time, FDG PET/CT has become part of the routine staging and evaluation of patients with cutaneous melanoma. There is growing interest in using FDG PET/CT measurements to predict response to ICI therapy and/or target therapy. While semiquantitative values such as standardized uptake value (SUV) are limited for predicting outcome, new measures including tumor metabolic volume, total lesion glycolysis and radiomics seem promising as potential imaging biomarkers for nuclear medicine. The aim of this review, prepared by an interdisciplinary group of experts, is to take stock of the current literature on radiomics approaches that could improve outcomes in CM.


Assuntos
Fluordesoxiglucose F18 , Melanoma , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Humanos , Melanoma/diagnóstico por imagem , Melanoma/tratamento farmacológico , Melanoma/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/tratamento farmacológico , Radiômica
12.
PLoS One ; 19(7): e0301919, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38968191

RESUMO

INTRODUCTION: Brain positron emission tomography/computed tomography (PET/CT) scans are useful for identifying the cause of dementia by evaluating glucose metabolism in the brain with F-18-fluorodeoxyglucose or Aß deposition with F-18-florbetaben. However, since imaging time ranges from 10 to 30 minutes, movements during the examination might result in image artifacts, which interfere with diagnosis. To solve this problem, data-driven brain motion correction (DDBMC) techniques are capable of performing motion corrected reconstruction using highly accurate motion estimates with high temporal resolution. In this study, we investigated the effectiveness of DDBMC techniques on PET/CT images using a Hoffman phantom, involving continuous rotational and tilting motion, each expanded up to approximately 20 degrees. MATERIALS AND METHODS: Listmode imaging was performed using a Hoffman phantom that reproduced rotational and tilting motions of the head. Brain motion correction processing was performed on the obtained data. Reconstructed images with and without brain motion correction processing were compared. Visual evaluations by a nuclear medicine specialist and quantitative parameters of images with correction and reference still images were compared. RESULTS: Normalized Mean Squared Error (NMSE) results demonstrated the effectiveness of DDBMC in compensating for rotational and tilting motions during PET imaging. In Cases 1 and 2 involving rotational motion, NMSE decreased from 0.15-0.2 to approximately 0.01 with DDBMC, indicating a substantial reduction in differences from the reference image across various brain regions. In the Structural Similarity Index (SSIM), DDBMC improved it to above 0.96 Contrast assessment revealed notable improvements with DDBMC. In continuous rotational motion, % contrast increased from 42.4% to 73.5%, In tilting motion, % contrast increased from 52.3% to 64.5%, eliminating significant differences from the static reference image. These findings underscore the efficacy of DDBMC in enhancing image contrast and minimizing motion induced variations across different motion scenarios. CONCLUSIONS: DDBMC processing can effectively compensate for continuous rotational and tilting motion of the head during PET, with motion angles of approximately 20 degrees. However, a significant limitation of this study is the exclusive validation of the proposed method using a Hoffman phantom; its applicability to the human brain has not been investigated. Further research involving human subjects is necessary to assess the generalizability and reliability of the presented motion correction technique in real clinical scenarios.


Assuntos
Encéfalo , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Humanos , Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Artefatos , Tomografia por Emissão de Pósitrons/métodos , Movimento (Física) , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18
13.
Cancer Imaging ; 24(1): 93, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992707

RESUMO

BACKGROUND: Dynamic contrast-enhanced-MRI (DCE-MRI) is able to study bone marrow angiogenesis in patients with multiple myeloma (MM) and asymptomatic precursor diseases but its role in the management of MM has not yet been established. The aims of this prospective study was to compare DCE-MRI-based parameters between all monoclonal plasma cell disease stages in order to find out discriminatory parameters and to seek correlations with other diffusion-weighted MRI and positron emission tomography (PET)-based biomarkers in a hybrid simultaneous whole-body-2-[18F]fluorodeoxyglucose (FDG)-PET/MRI (WB-2-[18F]FDG-PET/MRI) imaging approach. METHODS: Patients with newly diagnosed Monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM) or symptomatic MM according to international myeloma working group and underwent WB-2-[18F]FDG-PET/MRI imaging including bone marrow DCE sequences at the Nantes University Hospital were prospectively enrolled in this study before receiving treatment. RESULTS: One hundred and sixty-seven patients (N = 167, mean age: 64 years ± 11 [Standard deviation], 66 males) were considered for the analysis. DCE-MRI-based Peak Enhancement Intensity (PEI), Time to PEI (TPEI) and their maximum intensity time ratio (MITR: PEI/TPEI) values were significantly different between the different monoclonal plasma cell disease stages, PEI values increasing and TPEI values decreasing progressively along the spectrum of plasma cell disorders, from MGUS stage to symptomatic multiple myeloma. PEI values were significantly higher in patients with diffuse bone marrow involvement (either in PET or in MRI images) than in those without diffuse bone marrow involvement, unlike TPEI values. PEI and TPEI values were not significantly different between patients with or without focal bone lesions. CONCLUSION: Different DCE-MRI-based parameters (PEI, TPEI, MITR) could significantly differentiate all monoclonal plasma cell disease stages and complemented conventional MRI and PET-based biomarkers.


Assuntos
Imagem de Difusão por Ressonância Magnética , Fluordesoxiglucose F18 , Mieloma Múltiplo , Tomografia por Emissão de Pósitrons , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Mieloma Múltiplo/diagnóstico por imagem , Estudos Prospectivos , Imagem de Difusão por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Imageamento por Ressonância Magnética/métodos , Gamopatia Monoclonal de Significância Indeterminada/diagnóstico por imagem , Meios de Contraste , Imagem Multimodal/métodos , Compostos Radiofarmacêuticos , Imagem Corporal Total/métodos , Idoso de 80 Anos ou mais , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia
14.
Cancer Imaging ; 24(1): 90, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982546

RESUMO

BACKGROUND: Exploring the value of baseline and early 18F-FDG PET/CT evaluations in prediction PFS in ER+/HER2- metastatic breast cancer patients treated with a cyclin-dependent kinase inhibitor in combination with an endocrine therapy. METHODS: Sixty-six consecutive breast cancer patients who underwent a pre-therapeutic 18F-FDG PET/CT and a second PET/CT within the first 6 months of treatment were retrospectively included. Metabolic tumour volume (MTV) and total lesion glycolysis (TLG) and Dmax, which represents tumour dissemination and is defined as the distance between the two most distant lesions, were computed. The variation in these parameters between baseline and early evaluation PET as well as therapeutic evaluation using PERCIST were assessed as prognosticators of PFS at 18 months. RESULTS: The median follow-up was equal to 22.5 months. Thirty progressions occurred (45.4%). The average time to event was 17.8 ± 10.4 months. At baseline, Dmax was the only predictive metabolic parameter. Patients with a baseline Dmax ≤ 18.10 cm had a significantly better 18 m-PFS survival than the others: 69.2% (7.7%) versus 36.7% (8.8%), p = 0.017. There was no association between PERCIST evaluation and 18 m-PFS status (p = 0.149) and there was no difference in 18 m-PFS status between patients classified as complete, partial metabolic responders or having stable metabolic disease. CONCLUSION: Disease spread at baseline PET, as assessed by Dmax, is predictive of an event occurring within 18 months. In the absence of early metabolic progression, which occurs in 15% of patients, treatment should be continued regardless of the quality of the initial response to treatment.


Assuntos
Neoplasias da Mama , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Humanos , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Adulto , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/uso terapêutico , Quinases Ciclina-Dependentes/antagonistas & inibidores , Metástase Neoplásica , Prognóstico
15.
Mol Imaging ; 23: 15353508241257924, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952399

RESUMO

Chimeric antigen receptor (CAR)-T cell-based immunotherapy has emerged as a path-breaking strategy for certain hematological malignancies. Assessment of the response to CAR-T therapy using quantitative imaging techniques such as positron emission tomography/computed tomography (PET/CT) has been broadly investigated. However, the definitive role of PET/CT in CAR-T therapy remains to be established. [18F]FDG PET/CT has demonstrated high sensitivity and specificity for differentiating patients with a partial and complete response after CAR-T therapy in lymphoma. The early therapeutic response and immune-related adverse effects such as cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome can also be detected on [18F]FDG PET images. In otherwise asymptomatic lymphoma patients with partial response following CAR-T therapy, the only positive findings could be abnormal PET/CT results. In multiple myeloma, a negative [18F]FDG PET/CT after receiving B-cell maturation antigen-directed CAR-T therapy has been associated with a favorable prognosis. In leukemia, [18F]FDG PET/CT can detect extramedullary metastases and treatment responses after therapy. Hence, PET/CT is a valuable imaging tool for patients undergoing CAR-T therapy for pretreatment evaluation, monitoring treatment response, assessing safety, and guiding therapeutic strategies. Developing guidelines with standardized cutoff values for various PET parameters and tumor cell-specific tracers may improve the efficacy and safety of CAR-T therapy.


Assuntos
Neoplasias Hematológicas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/diagnóstico por imagem , Neoplasias Hematológicas/imunologia , Imunoterapia Adotiva/métodos , Imunoterapia/métodos , Receptores de Antígenos Quiméricos/uso terapêutico , Fluordesoxiglucose F18
16.
J Vis Exp ; (208)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38912787

RESUMO

The authors have developed a paradigm using positron emission tomography (PET) with multiple radiopharmaceutical tracers that combines measurements of cerebral metabolic rate of glucose (CMRGlc), cerebral metabolic rate of oxygen (CMRO2), cerebral blood flow (CBF), and cerebral blood volume (CBV), culminating in estimates of brain aerobic glycolysis (AG). These in vivo estimates of oxidative and non-oxidative glucose metabolism are pertinent to the study of the human brain in health and disease. The latest positron emission tomography-computed tomography (PET-CT) scanners provide time-of-flight (TOF) imaging and critical improvements in spatial resolution and reduction of artifacts. This has led to significantly improved imaging with lower radiotracer doses. Optimized methods for the latest PET-CT scanners involve administering a sequence of inhaled 15O-labeled carbon monoxide (CO) and oxygen (O2), intravenous 15O-labeled water (H2O), and 18F-deoxyglucose (FDG)-all within 2-h or 3-h scan sessions that yield high-resolution, quantitative measurements of CMRGlc, CMRO2, CBF, CBV, and AG. This methods paper describes practical aspects of scanning designed for quantifying brain metabolism with tracer kinetic models and arterial blood samples and provides examples of imaging measurements of human brain metabolism.


Assuntos
Encéfalo , Glucose , Oxigênio , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Humanos , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Glucose/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/química , Oxigênio/metabolismo , Fluordesoxiglucose F18/farmacocinética , Radioisótopos de Oxigênio/farmacocinética , Radioisótopos de Oxigênio/metabolismo , Circulação Cerebrovascular/fisiologia
17.
J Pediatr Hematol Oncol ; 46(5): e272-e276, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38912835

RESUMO

BACKGROUND/AIM: 18F-fluoro-2-deoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is a diagnostic tool widely used in adult oncology and some pediatric oncological settings. There are no established recommendations for the use of this imaging modality in pediatric malignant germ cell tumors (mGCT), however. Our aim is to evaluate the role of 18F-FDG PET/CT in the restaging of mGCT after chemotherapy in children and adolescents. METHODS: We retrospectively reviewed patients with mGCT treated in Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) centers who underwent 18F-FDG PET/CT between 2011 and 2021. RESULTS: Seventeen patients (median age 13 y) were included in the study. In 14 patients, 18F-FDG PET/CT was performed at diagnosis; 12 showed pathologic uptake. The 2 18F-FDG PET/CT negative cases were histologically defined as yolk sac tumor (YST) and mixed (chorioncarcinoma, YST). Nine of the 12 patients who had pathologic 18F-FDG PET/CT at diagnosis repeated the examination after neoadjuvant chemotherapy, before, second look surgery. In 5 cases, no pathologic uptake was evident. Histology showed necrosis alone in 4 cases and necrosis and mature teratoma in 1. In 3 of the 6 cases with pathologic uptake (2 of 6 patients did not perform the examination at diagnosis), histology showed persistence of malignant component, whereas in the remaining 3 cases, necrosis and mature teratoma were present. CONCLUSION: In our review of a series of children with mGCT, 18F-FDG PET/CT after neoadjuvant chemotherapy showed 1 of 5 false negatives and was unable to discriminate between residual malignant component and mature teratoma.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Embrionárias de Células Germinativas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Adolescente , Criança , Masculino , Neoplasias Embrionárias de Células Germinativas/diagnóstico por imagem , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/patologia , Estudos Retrospectivos , Feminino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Pré-Escolar , Compostos Radiofarmacêuticos
18.
Niger J Clin Pract ; 27(6): 748-753, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38943299

RESUMO

BACKGROUND: Some parameters of 18F-2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) can predict tumor chemosensitivity and survival in patients with head and neck squamous cell carcinoma (HNSCC). AIM: The aim of the study was to investigate the prognostic value of pre- and post-treatment maximum standardized uptake values (SUVmax) in 18F-FDG PET/CT imaging for predicting mortality in patients with HNSCC, as well as its prognostic value in terms of disease progression, overall survival (OS), and progression-free survival (PFS). METHODS: This retrospective study included 37 patients with a histopathological diagnosis of HNSCCs between 2015 and 2018. In patients with HNSCC, the first 18F-FDG PET/CT imaging was performed for pre-treatment staging, and the second imaging was performed to evaluate post-treatment response. In these imaging studies, SUVmax values of the primary tumor before and after treatment were determined. After the second imaging, patients were re-evaluated and followed up. ROC analysis was used to determine the predictive value of 18F-FDG PET/CT SUVmax parameters in terms of death and progression, and Cox regression analysis was used to investigate the prognostic value in terms of OS and PFS. RESULTS: Cut-off value 15 for SUVmax1 (pre-treatment) had a significant predictive value for mortality (P = 0.02). Cut-off value 3.1 for SUVmax2 (post-treatment) had a significant predictive value for progression (P = 0.024). In univariate analysis, both SUVmax1 and SUVmax2 values were significant prognostic factors for OS (P = 0.047, P = 0.004). However, for PFS, only the SUVmax2 value was a significant prognostic factor (P = 0.001). CONCLUSION: SUVmax1 value of the primary tumor at diagnosis in HNSCC patients has a predictive value for mortality and a prognostic value for OS. However, the SUVmax2 value in the primary tumor after treatment is a predictive factor for progression and a prognostic factor for both OS and PFS.


Assuntos
Quimiorradioterapia , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Prognóstico , Neoplasias de Cabeça e Pescoço/terapia , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Idoso , Quimiorradioterapia/métodos , Adulto , Valor Preditivo dos Testes , Progressão da Doença
19.
J Nucl Med Technol ; 52(2): 115-120, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839114

RESUMO

Brown fat can present challenges in patients with cancer who undergo 18F-FDG PET scans. Uptake of 18F-FDG by brown fat can obscure or appear similar to active oncologic lesions, causing clinical challenges in PET interpretation. Small, retrospective studies have reported environmental and pharmacologic interventions for suppressing brown fat uptake on PET; however, there is no clear consensus on best practices. We sought to characterize practice patterns for strategies to mitigate brown fat uptake of 18F-FDG during PET scanning. Methods: A survey was developed and distributed via e-mail LISTSERV to members of the Children's Oncology Group diagnostic imaging committee, the Society for Nuclear Medicine and Molecular Imaging pediatric imaging council, and the Society of Chiefs of Radiology at Children's Hospitals between April 2022 and February 2023. Responses were stored anonymously in REDCap, aggregated, and summarized using descriptive statistics. Results: Fifty-five complete responses were submitted: 51 (93%) faculty and fellow-level physicians, 2 (4%) technologists, and 2 (4%) respondents not reporting their rank. There were 43 unique institutions represented, including 5 (12%) outside the United States. Thirty-eight of 41 (93%) institutions that responded on environmental interventions reported using warm blankets in the infusion and scanning rooms. Less than a third (n = 13, 30%) of institutions reported use of a pharmacologic intervention, with propranolol (n = 5, 38%) being most common, followed by fentanyl (n = 4, 31%), diazepam (n = 2, 15%), and diazepam plus propranolol (n = 2, 15%). Selection criteria for pharmacologic intervention varied, with the most common criterion being brown fat uptake on a prior scan (n = 6, 45%). Conclusion: Clinical practices to mitigate brown fat uptake on pediatric 18F-FDG PET vary widely. Simple environmental interventions including warm blankets or increasing the temperature of the injection and scanning rooms were not universally reported. Less than a third of institutions use pharmacologic agents for brown fat mitigation.


Assuntos
Tecido Adiposo Marrom , Fluordesoxiglucose F18 , Hospitais Pediátricos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Marrom/metabolismo , Inquéritos e Questionários , Internacionalidade , Transporte Biológico , Criança
20.
J Nucl Med Technol ; 52(2): 173-174, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839116

RESUMO

In a 32-y-old man with neurofibromatosis type 1, 18F-FDG PET/CT incidentally revealed a vesicourachal diverticulum, a rare anatomic variant. The PET/CT, performed for staging a malignant peripheral nerve sheath tumor, highlighted a distinctive 18F-FDG-avid pattern crucial for accurate diagnosis. Recognizing such features enhances disease assessment and clarifies distinctions between benign urogenital anomalies and malignancies in 18F-FDG PET/CT staging.


Assuntos
Divertículo , Fluordesoxiglucose F18 , Achados Incidentais , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Masculino , Adulto , Divertículo/diagnóstico por imagem , Transformação Celular Neoplásica , Estadiamento de Neoplasias , Neurofibromatose 1/diagnóstico por imagem , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/patologia , Bexiga Urinária/anormalidades
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