1.
Total-body PET Imaging: A New Frontier for the Assessment of Metabolic Disease and Obesity.
Chondronikola, M, Sarkar, S
PET clinics. 2021;(1):75-87
Abstract
Obesity and associated metabolic syndrome are a global public health issue. Understanding the pathophysiology of this systemic disease is of critical importance for the development of future therapeutic interventions to improve clinical outcomes. The multiorgan nature of the pathophysiology of obesity presents a unique challenge. Total-body PET imaging, either static or dynamic, provides a vital set of tools to study organ crosstalk. The visualization and quantification of tissue metabolic kinetics with total-body PET in health and disease provides essential information to better understand disease physiology and potentially develop diagnostic and therapeutic modalities.
2.
Role of positron emission tomography in thyroid and neuroendocrine tumors.
Treglia, G, Kroiss, AS, Piccardo, A, Lococo, F, Santhanam, P, Imperiale, A
Minerva endocrinologica. 2018;(3):341-355
Abstract
Positron emission tomography (PET) is an established imaging method in oncology. PET/computed tomography (PET/CT) and PET/magnetic resonance imaging (PET/MRI) are hybrid techniques which combine morphological information obtained by CT and MRI with functional data provided by PET. Several PET radiotracers evaluating different metabolic pathways or receptor status can be used to assess endocrine tumors such as thyroid tumors or neuroendocrine neoplasms (NENs). This review is focused to describe the role of PET imaging using different radiotracers in patients with thyroid tumors and NENs. The role of PET imaging with different radiotracers in several endocrine tumors including thyroid tumors, gastroenteropancreatic neoplasms, lung neuroendocrine neoplasms, pheochromocytomas and paragangliomas, and multiple endocrine neoplasia syndromes has been described. Fluorine-18 fluorodeoxyglucose (18F-FDG) PET evaluating the glucose metabolism provides useful diagnostic and prognostic information in patients with thyroid tumors. Iodine-124 (124I) assessing the iodine metabolism may be used for dosimetry and diagnostic purposes in thyroid tumors. In patients with NENs specific radiotracers can be used for diagnostic purposes such as somatostatin analogues labeled with gallium-68 (68Ga-DOTA-peptides) evaluating somatostatin receptor expression and fluorine-18 fluorodihydroxyphenylalanine (18F-FDOPA) assessing the uptake, decarboxylation and storage of amine precursors. One advantage of 68Ga-DOTA-peptides PET is to select patients with well-differentiated and inoperable NENs for peptide receptor radionuclide therapy. 18F-FDG PET may provide useful prognostic information in patients with high-grade NENs. PET imaging with different radiotracers is a useful functional imaging technique in the work-up of several endocrine tumors.
3.
Neuroimaging Applications in Restless Legs Syndrome.
Rizzo, G, Plazzi, G
International review of neurobiology. 2018;:31-64
Abstract
Neuroimaging studies provide information useful to understand the pathophysiology of restless legs syndrome. Molecular PET and SPECT imaging findings mainly supported dysfunction of dopaminergic pathways involving not only the nigrostriatal but also mesolimbic pathways. Magnetic resonance imaging (MRI) studies have used different techniques. Studies using iron-sensitive sequences supported the presence of a regionally variable low brain iron content, mainly at the level of substantia nigra and thalamus. The search for brain structural or microstructural abnormalities by voxel-based morphometry, diffusion tensor imaging or cortical thickness analysis has reported none or variable findings in restless legs syndrome patients, most of them in regions belonging to sensorimotor and limbic/nociceptive networks. Functional MRI studies have substantially demonstrated activation or connectivity changes in the same networks. Magnetic resonance spectroscopy studies showed metabolic changes in the thalamus, which is a hub of these networks. In summary, neuroimaging findings in restless legs syndrome support the presence of reduction of brain iron content, of dysfunction of mesolimbic and nigrostriatal dopaminergic pathways, and of abnormalities at level of limbic/nociceptive and sensorimotor networks.
4.
Phase II trial evaluating the efficacy of sorafenib (BAY 43-9006) and correlating early fluorodeoxyglucose positron emission tomography-CT response to outcome in patients with recurrent and/or metastatic head and neck cancer.
Lalami, Y, Garcia, C, Flamen, P, Ameye, L, Paesmans, M, Awada, A
Head & neck. 2016;(3):347-54
Abstract
BACKGROUND The purpose of this study was to assess the efficacy and safety of sorafenib in patients with recurrent/metastatic squamous cell carcinoma of the head and neck (SCCHN) and to explore the predictive value of early metabolic responses. METHODS Sorafenib was administered orally at 400 mg bid on a continuous basis. The primary endpoint was the response rate. Correlation of early (18)fluorodeoxyglucose (FDG) positron emission tomography (PET)-CT response to time-to-event outcomes was a secondary objective. RESULTS Twenty-three patients were included in this study. Grade 3 to 4 toxicities included fatigue (22%), hand-foot syndrome (9%), lymphopenia (17%), hyponatremia (39%), and hypophosphatemia (48%). One patient (5%) had a partial response (PR) and 12 patients (55%) had stable disease. Early metabolic response rate was 38%. Median progression-free survival (PFS) was 2.2 months in early metabolic nonresponders (13 of 21 patients) in comparison to 7.4 months in the 8 patients with class I early metabolic response (pā=ā.006). CONCLUSION Sorafenib showed a modest antitumor activity. Data suggest a possible role of (18)FDG PET metabolic response as an early predictor of a prolonged PFS.
5.
Systemic vascular inflammation in abdominal aortic aneurysm patients: a contrast-enhanced PET/CT study.
Morbelli, S, Ghigliotti, G, Spinella, G, Marini, C, Bossert, I, Cimmino, M, Pane, B, Rousas, N, Cittadini, G, Massollo, M, et al
The quarterly journal of nuclear medicine and molecular imaging : official publication of the Italian Association of Nuclear Medicine (AIMN) [and] the International Association of Radiopharmacology (IAR), [and] Section of the Society of.... 2014;(3):299-309
Abstract
AIM: The aim of this paper was to investigate the presence of systemic vascular inflammation and its relationship with risk factors and biomarkers of systemic inflammation related to atherosclerosis in asymptomatic abdominal aortic aneurysm (AAA) patients. METHODS Thirty AAA patients and 30 age-matched controls underwent contrast-enhanced 2-deoxy-2-[18F]fluoro-D-glucose (FDG) PET/CT. C-reactive protein, erythrocyte sedimentation rate, white blood cell count and differential, serum fibrinogen, D-dimer and full lipid panel were also evaluated. Region of interest analyses were performed to obtain target-to-background (TBR) metabolism of aorta, subclavian, carotid, iliac arteries and AAA. CT-based arterial calcium load (CL) was evaluated. Arterial Metabolism and CL intergroup differences were tested (unpaired t-test). Linear regression analysis was performed only between blood biomarkers on one side and both TBR and ACL of the arterial districts that resulted significantly different between patients and controls on the other. In all the analyses P values <0.05 were considered significant. RESULT FDG-uptake was higher with respect to controls in aorta, carotid and iliac arteries (P<0.01, P<0.007, P<0.04 respectively). AAA and aorta metabolism showed an inverse correlation with HDL-chol (P<0.02 and P<0.01, respectively) while only aorta showed a direct correlation with lymphocytes' count (P<0.02). Carotid metabolism was directly correlated with monocytes' count and C-reactive protein concentration (P<0.02 and P<0.004, respectively). CONCLUSION The present findings support the relevance of systemic vascular inflammation in all phases of atherosclerosis-related disorders. Moreover they confirm the concept that acute ischemic syndromes might represent the local result of a systemic inflammation rather than the focal involvement of a single arterial lesion.
6.
PET/CT imaging in inflammatory myopathies.
Al-Nahhas, A, Jawad, AS
Annals of the New York Academy of Sciences. 2011;:39-45
Abstract
Inflammatory muscle diseases are a group of muscle disorders characterized by muscle weakness, fatigue, and an association with malignancy and paraneoplastic syndrome. A diagnosis of idiopathic inflammatory myopathy is suggested by abnormal myometry and rising creatine kinase, but tissue diagnosis is also needed. Magnetic resonance imaging (MRI) helps localize the appropriate site of biopsy, demonstrate the extent of muscle involvement, and monitor the response to therapy. However, the sensitivity of magnetic resonance (MR) is limited, and whole-body imaging is still far from routine. [(18) F]Fluoro-desoxy-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) is currently the ultimate metabolic imaging technique for the management of cancer. It has also been shown to detect inflammatory conditions and to monitor their response to treatment. The use of FDG PET in screening for underlying malignancies is widely reported and recommended in patients with paraneoplastic syndrome. Unfortunately, only a few reports have been published to show the value of FDG PET in inflammatory muscle diseases, which as we show herein, deserve further pursuit.