44 research outputs found

    The search for the primary tumor in metastasized gastroenteropancreatic neuroendocrine neoplasm.

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    Gastroenteropancreatic neuroendocrine tumors (NETs) often present as liver metastasis from a carcinoma of unknown primary. We recently showed that primary NETs from the pancreas, small intestine and stomach as well as their respective liver metastases differ from each other by the expression profile of the three genes CD302, PPWD1 and ABHB14B. The gene and protein expression of CD302, PPWD1, and ABHB14B was studied in abdominal NET metastases to identify the site of the respective primary tumors. Cryopreserved tissue from NET metastases collected in different institutions (group A: 29, group B: 50, group C: 132 specimens) were examined by comparative genomic hybridization (Agilent 105 K), gene expression analysis (Agilent 44 K) (groups A and B) and immunohistochemistry (group C). The data were blindly evaluated, i.e. without knowing the site of the primary. Gene expression analysis correctly revealed the primary in the ileum in 94 % of the cases of group A and in 58 % of group B. A pancreatic primary was predicted in 83 % (group A) and 20 % (group B), respectively. The combined sensitivity of group A and B was 75 % for ileal NETs and 38 % for pancreatic NETs. Immunohistochemical analysis of group C revealed an overall sensitivity of 80 %. Gene and protein expression analysis of CD302 and PPWD1 in NET metastases correctly identifies the primary in the pancreas or the ileum in 80 % of the cases, provided that the tissue is well preserved. Immunohistochemical profiling revealed CD302 as the best marker for ileal and PPWD1 for pancreatic detection

    Neuroendocrine Tumors of the Bronchopulmonary System (Typical and Atypical Carcinoid Tumors): Current Strategies in Diagnosis and Treatment. Conclusions of an Expert Meeting February 2011 in Weimar, Germany

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    Neuroendocrine tumors (NETs; syn. carcinoid tumors) are highly or moderately differentiated neoplasms. They comprise a large variety of rare and heterogeneous tumors with an estimated incidence of 3-5/100,000/year. They can arise in virtually every internal organ, but mainly occur in the gastroenteropancreatic and bronchopulmonary systems. Around 25% of the NETs are localized in the bronchopulmonary system. Approximately 2% of all lung tumors are NETs. According to the World Health Organization (WHO) classification of lung tumors, bronchopulmonary NETs are subdivided into typical carcinoids (TCs) and atypical carcinoids (ACs). The parameter with the highest impact on NET behavior and prognosis is the histological classification and staging according to the tumor/node/metastasis (TNM) system. The diagnosis of NETs is established by histological examination and the immunohistochemical detection of general neuroendocrine markers, such as chromogranin A (CgA) and synaptophysin. Serum markers and the use of functional imaging techniques are important additive tools to establish the diagnosis of a NET. The only curative option for lung NETs is complete surgical resection. Beyond that, the currently available interdisciplinary therapeutic options are local ablation, biotherapy (somatostatin analogues), or chemotherapy. New therapeutic options such as peptide receptor radionuclide therapy (PRRT) and molecularly targeted therapies achieve promising results and are under further evaluation. This report is a consensus summary of the interdisciplinary symposium ‘Neuroendocrine Tumors of the Lung and of the Gastroenteropancreatic System (GEP NET) - Expert Dialogue' held on February 25-26, 2011 in Weimar, Germany. At this conference, a panel of 23 German experts shared their knowledge and exchanged their thoughts about research, diagnosis, and clinical management of NETs, whereby special attention was paid to NETs of the respiratory trac

    pyam: Analysis and visualisation of integrated assessment and macro-energy scenarios [version 2; peer review: 3 approved]

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    The open-source Python package pyam provides a suite of features and methods for the analysis, validation and visualization of reference data and scenario results generated by integrated assessment models, macro-energy tools and other frameworks in the domain of energy transition, climate change mitigation and sustainable development. It bridges the gap between scenario processing and visualisation solutions that are "hard-wired" to specific modelling frameworks and generic data analysis or plotting packages. The package aims to facilitate reproducibility and reliability of scenario processing, validation and analysis by providing well-tested and documented methods for working with timeseries data in the context of climate policy and energy systems. It supports various data formats, including sub-annual resolution using continuous time representation and "representative timeslices". The pyam package can be useful for modelers generating scenario results using their own tools as well as researchers and analysts working with existing scenario ensembles such as those supporting the IPCC reports or produced in research projects. It is structured in a way that it can be applied irrespective of a user's domain expertise or level of Python knowledge, supporting experts as well as novice users. The code base is implemented following best practices of collaborative scientific-software development. This manuscript describes the design principles of the package and the types of data which can be handled. The usefulness of pyam is illustrated by highlighting several recent applications

    The joint IAEA, EANM, and SNMMI practical guidance on peptide receptor radionuclide therapy (PRRNT) in neuroendocrine tumours

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    Peptide receptor radionuclide therapy (PRRNT) is a molecularly targeted radiation therapy involving the systemic administration of a radiolabelled peptide designed to target with high affinity and specificity receptors overexpressed on tumours. PRRNT employing the radiotagged somatostatin receptor agonists (90)Y-DOTATOC ([(90)Y-DOTA(0),Tyr(3)]-octreotide) or (177)Lu-DOTATATE ([(177)Lu-DOTA(0),Tyr(3),Thr(8)]-octreotide or [(177)Lu-DOTA(0),Tyr(3)]-octreotate) have been successfully used for the past 15 years to target metastatic or inoperable neuroendocrine tumours expressing the somatostatin receptor subtype 2. Accumulated evidence from clinical experience indicates that these tumours can be subjected to a high absorbed dose which leads to partial or complete objective responses in up to 30 % of treated patients. Survival analyses indicate that patients presenting with high tumour receptor expression at study entry and receiving (177)Lu-DOTATATE or (90)Y-DOTATOC treatment show significantly higher objective responses, leading to longer survival and improved quality of life. Side effects of PRRNT are typically seen in the kidneys and bone marrow. These, however, are usually mild provided adequate protective measures are undertaken. Despite the large body of evidence regarding efficacy and clinical safety, PRRNT is still considered an investigational treatment and its implementation must comply with national legislation, and ethical guidelines concerning human therapeutic investigations. This guidance was formulated based on recent literature and leading experts’ opinions. It covers the rationale, indications and contraindications for PRRNT, assessment of treatment response and patient follow-up. This document is aimed at guiding nuclear medicine specialists in selecting likely candidates to receive PRRNT and to deliver the treatment in a safe and effective manner. This document is largely based on the book published through a joint international effort under the auspices of the Nuclear Medicine Section of the International Atomic Energy Agency
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