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Alkylating agents, such as streptozocin and dacarbazine, have been reported as active in neuroendocrine neoplasms (NENs). Temozolomide (TMZ) is an oral, potentially less toxic derivative of dacarbazine, which has shown activity both as a single agent and in combination with other drugs. Nevertheless, its role in NENs has not been well defined. Several retrospective and prospective phase I-II studies have been published describing its use in a variety of NENs. In a retrospective series, the combination of capecitabine and TMZ was reported to be associated with a particularly high tumour response in pancreatic NENs as a first-line treatment. Although in NENs, determination of the O6-methylguanine-DNA methyltransferase (MGMT) status has been suggested as a predictive biomarker of response, its role still remains investigational, awaiting validation along with the establishment of the optimal detection method. Metronomic schedules have been reported to potentially overcome MGMT-related drug resistance. Toxicity is manageable if well monitored. We reviewed the literature regarding pharmacological and clinical aspects of TMZ, focusing on specific settings of NENs, different schedules, toxicity and safety profiles, and potential predictive biomarkers of response. © 2015 S. Karger AG, Basel.

Background: Pulmonary carcinoids (PCs) are rare tumors. As there is a paucity of randomized studies, this expert consensus document represents an initiative by the European Neuroendocrine Tumor Society to provide guidance on their management. Patients and methods: Bibliographical searches were carried out in PubMed for the terms 'pulmonary neuroendocrine tumors', 'bronchial neuroendocrine tumors', 'bronchial carcinoid tumors', 'pulmonary carcinoid', 'pulmonary typical/atypical carcinoid', and 'pulmonary carcinoid and diagnosis/treatment/epidemiology/prognosis'. A systematic review of the relevant literature was carried out, followed by expert review. Results: PCs are well-differentiated neuroendocrine tumors and include low- and intermediate-grade malignant tumors, i.e. typical (TC) and atypical carcinoid (AC), respectively. Contrast CT scan is the diagnostic gold standard for PCs, but pathology examination is mandatory for their correct classification. Somatostatin receptor imaging may visualize nearly 80% of the primary tumors and is most sensitive for metastatic disease. Plasma chromogranin A can be increased in PCs. Surgery is the treatment of choice for PCs with the aim of removing the tumor and preserving as much lung tissue as possible. Resection of metastases should be considered whenever possible with curative intent. Somatostatin analogs are the first-line treatment of carcinoid syndrome and may be considered as first-line systemic antiproliferative treatment in unresectable PCs, particularly of low-grade TC and AC. Locoregional or radiotargeted therapies should be considered for metastatic disease. Systemic chemotherapy is used for progressive PCs, although cytotoxic regimens have demonstrated limited effects with etoposide and platinum combination the most commonly used, however, temozolomide has shown most clinical benefit. Conclusions: PCs are complex tumors which require a multidisciplinary approach and long-term follow-up. © The Author 2015. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved.

ENETS consensus guidelines for the management of bone and lung metastases from neuroendocrine tumors

ENETS Consensus Guidelines for the Standards of Care in Neuroendocrine Tumors : towards a standardized approach to the diagnosis of gastroenteropancreatic neuroendocrine tumors and their prognostic stratification

ENETS Consensus Guidelines for the Standards of Care in Neuroendocrine Tumors : Chemotherapy in Patients with Neuroendocrine Tumors

The ECL cell is the most common cell type in the oxyntic mucosa of the stomach. It is producing a number of peptides and amines where histamine and chromogranin A seems to be the most important and abundant products. Recent data indicate a direct correlation between ECL-cell mass and circulating chromogranin A levels. Chromogranin A and its splice products might serve as growth promoting agents in ECL-cell hyperplasia or gastric carcinoids.

Neuroendocrine gut and pancreatic tumors are known to contain and secret different peptide hormones and amines. During the last two decades, many radioimmunoassays and Elizas have been developed to analyze these substances in blood and urine, which has enabled clinicians to improve the diagnosis and monitoring of patients with various neuroendocrine tumors. Due to cost constraints in medical care, it is important to try to define the most useful biochemical markers from the clinical point of view. The glycoprotein chromogranin A has been shown to be a useful marker for diagnosing various neuroendocrine tumors, both by histopathology and circulating tumor markers. In patients with demonstrable endocrine tumors, about 90 percent of the patients present high circulating levels of chromogranin A. A hundred-fold increase of plasma chromogranin is seen in patients with midgut carcinoid tumors and liver metastases. The plasma levels of chromogranin A reflect the tumor mass and can be used for monitoring the patient during treatment and follow-up, although the day-to-day variation might be 30-40 percent. High circulating levels of the chromogranin A might be an indicator of bad prognosis in patients with malignant carcinoid tumors. Besides analyzing plasma chromogranin A, specific analyses such as urinary 5-HIAA in midgut carcinoid patients, serum gastrin in patients with Zollinger-Ellison syndrome and insulin/proinsulin in patients with hypoglycemia should be performed. In patients with small tumor masses or intermittent symptoms, provocative tests such as a meal stimulation test, secretin test or pentagastrin stimulation of tachykinin release can supplement the basal measurements of peptides and amines. To fully evaluate the growth potential in neuroendocrine tumors, traditional biochemical markers should be supplemented with indicators of growth proliferation (Ki-67, PCNA) and immunohistochemical staining for the adhesion molecule CD44 and the PDGF-alpha receptor. Finally, analysis of somatostatin receptor subtypes and induction of the enzymes 2-5A syntethase and PKR are of clinical value.

Context: Hypersecretion of PTHrP is a relatively common cause of malignancy-related hypercalcemia but has only been described in a few cases of neuroendocrine tumors (NET). Objective: The aim of this case report is to describe the clinical syndrome, complex therapeutic interventions, and unusual complications caused by persistent PTHrP hypersecretion in a patient with a pancreatic NET. Case Illustration: A 58-yr-old male patient presented with nonspecific abdominal pain and was found to have severe hypercalcemia secondary to a well-differentiated NET of the pancreas associated with extensive liver metastases. Elevated ionized calcium levels accompanied by low serum PTH and remarkably elevated PTHrP concentrations were consistent with PTHrP-related hypercalcemia that proved to be resistant to various chemotherapeutic regimens and supportive therapy. Partial control of the humoral syndrome was obtained only after the application of cytoreductive interventions and the introduction of various molecular targeted therapies. Due to persistent PTHrP action, bone disease emerged in the form of brown tumors. Discussion: The manifestation of paraneoplastic syndrome due to PTHrP hypersecretion, despite its rareness in NET, should be considered in the differential diagnosis of hypercalcemia in such tumors. Moreover, the appearance of bone lesions in this setting may be in the context of metabolic bone disease and could be misdiagnosed as bone metastases. (J Clin Endocrinol Metab 97: E627-E631, 2012)

ENETS consensus guidelines for the management of brain, cardiac and ovarian metastases from neuroendocrine tumors

The purpose of this guideline is to assist physicians caring for patients with neuroendocrine tumors in considering eligibility criteria for peptide receptor radionuclide therapy (PRRT), and in defining the minimum requirements for PRRT. This guideline also makes recommendations on what minimal patient, tumor, and treatment outcome characteristics should be reported for PRRT in order to make comparisons between studies possible. It is not this guideline's aim to give specific recommendations on the use of specific radiolabeled somatostatin analogs for PRRT because different analogs are being used, and their availability depends on national law and local permissions. Copyright (C) 2009 S. Karger AG, Basel

Recent progress in ultra high vacuum surface experiments allows detailed investigations of the physical and chemical parameters governing astronomically relevant solid state processes on icy dust grains. In this proceeding four questions are shortly addressed that are related to the infrared signature, the thermal and photodesorption behavior and the chemical reactivity of interstellar ice analogues.