Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Somatostatin is a neuropeptide that confers a wide range of pharmacological properties. Indium-111-tagged pentetreotide ((111)In-P) is a radiolabeled analogue of somatostatin indicated for the in vivo scintigraphic localization of neuroendocrine tumors (NET). In cases of NET of the gastro-intestinal tract we describe the sensitivity compared to conventional anatomical imaging modalities and especially the possibility that (111)In-P may change therapeutic management into up one fourth of the patients. In cases of small cell lung carcinoma it has been used for the evaluation of somatostatin receptor status and a substantial tool for differentiation between limited and extensive disease, especially when combined with anatomical imaging methods. We also describe the radiolabeled with yttrium-90 or lutetium-177 somatostatin analogue peptides in the treatment of NET and also the use of (111)In-P for the selection of patients for targeted treatment.
Hell J Nucl Med
PMID:Somatostatin receptor imaging with (111)In-pentetreotide in gastro-intestinal tract and lung neuroendocrine tumors-Impact on targeted treatment. 2080 90

Previous reports suggested the accumulation of technetium-99m-depreotide trifluoroacetate ((99m)Tc-D) at the sites of active infection or inflammation. Binding of depreotide to over-expressed somatostatin receptors in activated lymphocytes and macrophages probably accounts for the depiction of inflammation. We speculated that myocardial inflammation could also be illustrated by (99m)Tc-D scintigraphy. We report on 3 patients with the clinical diagnosis of myocarditis of various etiologies, in which (99m)Tc-D SPET/CT demonstrated obvious tracer uptake in the myocardium of the left ventricle. In conclusion, we suggest that depreotide imaging can depict myocardial inflammation, thus supporting clinical diagnosis.
Hell J Nucl Med
PMID:Imaging myocardial inflammation of various etiologies with 99mTc-depreotide SPET/CT. 2208 46

Our aim was to evaluate the different clinical value of (111)In-pentetreotide hybrid SPET/CT versus SPET alone in detecting carcinoid tumours located in the thoracic and abdominal region. Twenty-four patients with carcinoid tumours histologically proven (13 of abdominal origin, 11 of thoracic origin) underwent (111)In-pentetreotide SPET/CT with hybrid system (Millennium VG with Hawkeye, G.E.M.S., USA) composed of a dual head gamma camera equipped with a low dose X-ray tube. Single photon emission tomography images were performed 4h and 24h after (111)In-pentetreotide intravenous administration, while SPET/CT co-registered images were performed at 4h. Scintigraphic images were first evaluated alone and then re-interpreted by adding transmission fused data. Nine of the 13 patients with tumours of abdominal origin showed pathological SPET images, while 4/13 were negative. Seven out of the 11 patients with tumour of thoracic origin had pathological SPET findings, while 4/11 were negative. In all, 11/24 subjects disclosed abdominal pathological uptake and 10/24 thoracic. In 6/11 abdominal cases SPET/CT allowed anatomical localization of lesions, while in 2/10 in thoracic cases. Additional data were provided by SPET/CT in 8/24 cases (6 abdominal, 2 thoracic), by transmission images characterized as lesions not expressing somatostatin receptors. Sensitivity of SPET alone in all carcinoids was 72%, negative predictive value (NPV) was 50% and accuracy was 78%. Considering abdominal lesions (independently of the origin) sensitivity of SPET alone was 64.7%, NPV was 40%, accuracy was 71.4%. For thoracic lesions sensitivity of SPET alone was 83.3%, NPV was 66.7% and accuracy was 87.5%. For SPET/CT considering together all carcinoids and also separately lesions of abdominal and of thoracic origin, sensitivity, NPV and accuracy were always 100%. In conclusion, SPET/CT imaging was more useful to anatomically detect carcinoids either in abdomen or in thorax and specifically lesions not expressing somatostatin receptors, as compared to SPET alone.
Hell J Nucl Med
PMID:(111)In-pentetreotide SPET/CT in carcinoid tumours: is the role of hybrid systems advantageous in abdominal or thoracic lesions? 2208 49

Somatostatin analogues (SSA), both radiolabeled and unlabeled play an important role in the management of carcinoid tumors. They are often administered in parallel, the unlabeled analogue for treating the carcinoid tumors' symptoms and the radiolabeled one for imaging tumors foci. There is a debate about when is the optimum time for a somatostatin receptor scintigraphy during treatment. Opinions are divided, with some authors suggesting stopping SSA treatment, while others do not. Our aim was to try to explore pharmacokinetics behind the radiolabeled peptide administration in the presence of circulating in blood unlabeled SSA, by using a model of "law of mass". Applying the pharmacokinetic data from the manufacturers' Prescription Information Sheet in a formula describing competitive binding, led to a reduced uptake for the radiolabeled peptide in the presence of the unlabeled peptide, in comparison with standalone radiolabeled peptide administration, regardless of the total number of available receptors. We provide data that unlabeled somatostatin should be withdrawn for no less than 14 days before the labeled SSA is administered, because biotherapy agents interfere with both diagnostic and therepeutic nuclear medicine procedures. Further research is needed to reach secure conclusions on patient medication management before diagnostic scans or therapeutic administrations in nuclear medicine. In conclusion, by waiting at least 6 half-lives (14 days), after the unlabeled SSA administration, the radiolabeled receptor uptake increased two-fold to three-fold, as compared to simultaneous administration of radiolabeled and unlabeled peptides depending on which SSA was used.
Hell J Nucl Med
PMID:A chemical model suggesting the maximum radiolabeled somatostatin analogue tumor uptake, in the presence of unlabeled somatostatin. 2241 13

Myocarditis may present clinically with a wide range of manifestations and often remains unrecognized. The diagnosis of myocarditis traditionally has been based on histological findings, but endomyocardial biopsy has a low sensitivity and clinicians are reluctant to proceed with an invasive diagnostic technique. Among newer diagnostic approaches, cardiac magnetic resonance imaging has gained acceptance as an efficient noninvasive tool to determine myocardial inflammation. In this context, imaging with radiolabeled somatostatin analogues could also be relevant because of their ability to delineate inflammatory sites. In conclusion, a case is presented in which somatostatin receptor imaging of the myocardium with (99m)Tc-depreotide tomography was used in the assessment of viral myocarditis.
Hell J Nucl Med
PMID:Somatostatin analogue scintigraphy in a patient with viral myocarditis. 2274 Nov 49

Bronchial carcinoids (BC) are rare well-differentiated neuroendocrine tumours (NET) sub-classified into typical (TC) and atypical carcinoids (AC). A correct pathological identification in the pre-operative setting is a key element for planning the best strategy of care, considering the different biological behavior of TC and AC. Controversial results have been reported on the diagnostic accuracy of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) in BC. On the other hand, there is increasing evidence supporting the use of PET with somatostatin analogues (dotanoc, dotatoc or dotatate) labeled with gallium-68 ((68)Ga) in pulmonary NET. Based on information obtained by using different radiopharmaceuticals and different (68)Ga labeled somatostatin analogues in PET and PET/CT studies, we are able to diagnose BC. In conclusion, by using somatostatin receptor imaging and (18)F-FDG PET/CT scan, we can differentiate BC from benign pulmonary lesions and TC from AC by specific diagnostic patterns. Clinical trials on larger groups of patient would allow for a better and "tailored" therapeutic strategy in NET patients using dual-tracer PET/CT to identify BC and distinguish between TC and AC.
Hell J Nucl Med
PMID:Which is the best strategy for diagnosing bronchial carcinoid tumours? The role of dual tracer PET/CT scan. 2456 74

Neuroendocrine tumors (neuroendocrine tumors-NET) are a heterogeneous group of neoplasms with a common embryological origin and diverse biological behavior, derived from cells of the neuroendocrine system, the system APUD (amine precursor uptake and decarboxylation). They are characterized by overexpression of all five somatostatin receptors (SSTR1-SSTR5), particularly type 2 (SST2). Surgical resection of the tumor is the treatment option, with a possibility of complete remission in patients with limited disease. Somatostatin analogs (octreotide and lanreotide) are the treatment of choice in patients with residual disease, particularly when it comes to NET non-pancreatic origin. Systemic chemotherapy is administered primarily to patients with poorly differentiated carcinomas. PRRT treatment is recommended in case of non-responsiveness of the disease. The ideal candidates for PRRT are patients with unresectable disease of high and intermediate differentiation. Somatostatine analogs radiolabelled with Indium-111 ((111)In), Yttrium-90 ((90)Y), Lutetium-177 ((177)Lu) and Bismuth-213 ((213)Bi), are selectively concentrated in the tumor cells, causing maximum tissue damage to tumors and with fewer effects on healthy tissue and the immune system. In the current review, it was demonstrated that patients with unresectable grade 1 or 2 disease showed increased PFS (progression free survival) and OS (overall survival), while quality of life was improved after PRRT treatment as compared to somatostatin analogs, chemotherapy and other targeted therapies.
Hell J Nucl Med
PMID:[Neuroendocrine tumors: Peptide receptors radionuclide therapy (PRRT)]. 2733 Dec 18

Dear Editor, In this journal, a few years ago, we presented a Bayesian (critical) appraisal of the-then recent-American Endocrine Society's guidelines regarding the diagnosis and management of pheochromocytoma/paraganglioma (PPG). This year, the European Society of Nuclear Medicine and the Society of Nuclear Medicine and Molecular Imaging have introduced new guidelines regarding functional imaging (i.e. by means of Nuclear Medicine modalities) of PPG. In light of this, we believe that it is appropriate to present a new relevant Bayesian assessment. In the new guidelines the following functional imaging modalities are covered: iodine-123-metaiodobenzylguanidine (123I-MIBG) single photon emission tomography (SPET), indium-111-diethylenetriamine pentaacetic acid (111In-DTPA)-pentetreotide (111In-pentetreotide) SPET, fluorine-18-fluorodihydroxyphenylalanine (18F-FDOPA) positron emission tomography (PET), 18F-fluorodeoxyglucose (18F-FDG) PET and PET with various gallium-68-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (168Ga-DOTA)-coupled somatostatin agonists (68Ga-SSTa). Based on a pretest probability of 15% for extra-adrenal disease and the reported sensitivity and specificity for each modality, we calculated likelihood ratios (LR) for a positive and a negative test (LR+ and LR-, respectively). In the absence of a given specificity in the guidelines we used levels of 55% for 18F-FDG and 85% for 68Ga-SSTa (the latter is a level that we used in our previous assessment), which have been validated in a recent meta-analysis. Using LR+ and LR- with Fagan's nomograms we calculated the post-test probability of extra-adrenal PPG. Only the LR+ for 18F-FDOPA was over 10 and no LR- was lower than 0.1, shifting to an important degree the probability of a diagnosis (clinicians have to bear in mind that an LR- may not be useful, since absence of radionuclide uptake does not imply absence of PPG if biochemistry is positive). It is evident that functional imaging of PPG has become more diversified and tailored according to each patient's history and genetic background. Nevertheless, the diagnostic characteristics of all methods (biochemical and imaging) are still not perfect; they are rather complimentary to each other. Biochemical evaluation should be done first, since functional imaging of PPG is advised to be performed in patients with biochemically-proven disease.
Hell J Nucl Med
PMID:A Bayesian look at the new 2019 guidelines for imaging of pheochromocytoma/paraganglioma with emphasis on extra-adrenal disease. 3127 58


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