Abstract library

33 results for "Ene".
#3049 Organoid Models of Neuroendocrine Cell Growth and Tumorigenesis
Introduction: A paucity of in vitro and in vivo models has limited the study of Neuroendocrine neoplasms (NENs). Moreover, little is known about normal neuroendocrine (NE) cells and how they contribute to NEN formation.
Conference: 17th Annual ENETS Conference 2020 (2020)
Category: Basic Science - In vitro models, tumor growth, CTCs
Presenting Author: PhD Talya Dayton
#12 Chromogranin A as a predictor of progression, regression or stable disease in ileo-cecal (midgut) carcinoid tumors
Introduction: A general characteristic for NETs is their expression of certain proteins, such as chromogranin A (CgA), which is released from the dense core vesicles of NE cells, occasionally together with cell specific hormones, such as gastrin and serotonin. Plasma CgA seems to be closely related to tumor burden of intestinal carcinoid tumors in humans.
Conference: 7th Annual ENETS Conference (2010)
Category: Clinical
Presenting Author: Kenneth Jensen
#18 Long-acting release octreotide induce complete response in type 1 gastric carcinoid tumors
Introduction: Gastric endocrine tumors (GET) are increasingly recognized due to expanding indications of upper gastrointestinal endoscopy. Often silent and benign, GET may also be aggressive when sporadic and may sometimes mimic the course of gastric adenocarcinoma. Current incidence of GETs is estimated at around 8% of digestive endocrine tumors. Yearly age-adjusted incidence is around 0.2 per population of 100,000. Gastric carcinoids (ECLomas) develop from gastric enterochromaffin-like cells (ECL cells) in response to chronically elevated gastrin. Type 1 tumors (ECLomas in the course of atrophic gastritis) may occur in conditions of achlorhydria secondary to auto-immune atrophic fundic gastritis. It occurs mostly in women and they are non-functioning tumors, typically found during upper GI endoscopy performed for dyspepsia. ECLomas present frequently as multiple polyps, usually < 1 cm in diameter in the gastric fundus. Type 1 tumors are almost exclusively benign lesions with little risk of deep invasion of the gastric parietal wall. The neoplastic ECL cells become progressively dedifferentiated with an increasing number of Ki-67 immunoreactive (IR) cell nuclei. In addition, there is a substantial decrease in argynophil and IR NE cells that can be visualized by conventional methods. ECLomas secondary to hypergastrinemia should be closely followed for signs of clinical and histopathological tumor progression. Such ECLomas deserve early, active, radical surgical treatment.
Traditionally, gastric carcinoid type 1 (GCA1s) are endoscopically or surgically removed, depending on the number, appearance and size of the tumors. Antrectomy, with surgical excision of the majority of the G cells, is thought to facilitate regression of these tumors by removing the source of excessive gastrin secretion; however, the long-term benefits of antrectomy still remain uncertain. Although proton pump inhibitors are effective in reducing hypergastrinemia-induced gastric acid hypersecretion in GCA2, they do not affect ECL-cell hyperplasia, and therefore their role in GCA1 is limited. Moreover, in selected cases, significant reduction of hypergastrinemia does not prevent development of ECL carcinoid, suggesting that, in addition to hypergastrinemia, other pathogenic or genetic factors may be involved. Treatment with somatostatin analogues (SSA) might impede ECL-cell hyperplasia by suppressing gastrin secretion and/or by a direct anti-proliferative effect on ECL cells. Treatment with SSAs in GCA1 leads to a substantial tumor load reduction, with a concomitant decrease of serum gastrin levels. Published data indicate an important anti-proliferative effect of SSA on ECL cells, providing clinical benefit and obviating, at least temporarily, the need for invasive therapies for GCA1. Morphometric studies demonstrated that, while antrectomy specifically decreased the volume of ECL cells versus the total volume of endocrine cells, octreotide reduces the overall endocrine cell volume. Although the number of treated patients is small, it has been suggested that SSA may exert important anti-proliferative effects either directly, by inhibiting ECL-cells proliferation, or indirectly through suppression of gastrin hypersecretion.
Conference: 7th Annual ENETS Conference (2010)
Category: Clinical
Presenting Author: MD Ricardo Caponero
#78 The diagnostic and prognostic value of elevated proGRP levels in well- and moderately differentiated neuroendocrine tumors
Introduction: Chromogranin A (CgA) is the most frequently used marker in well- (grade 1) and moderately (grade 2) differentiated NETs. Although CgA is a more sensitive marker than the 5-HIAA, which was widely used until the last decade, CgA has some limitations. False-positively elevated CgA may occur in renal impairment, atrophic gastritis and during treatment of proton-pump inhibitors. Progastrin-releasing peptide (proGRP) was recently reported as a promising tumor marker for small cell lung cancer. Limited data suggests that ProGRP may be a potential tumor marker in NE tumors.
Conference: 7th Annual ENETS Conference (2010)
Category: Basic
Presenting Author: Msc Catharina M Korse
#138 The use of F-18-FDG-PET for patients with neuroendocrine tumors
Introduction: Neoplastic tissue exhibits high glucose utilization, which can be imaged by 18F-Fluorodeoxyglucose-positron emission tomography (FDG-PET). Whether FDG-PET is useful for neuroendocrine (NE) tumors, however, is questionable, due to the slow growth rate often observed in these tumors.
Conference: 7th Annual ENETS Conference (2010)
Category: Clinical
Presenting Author: M.Sc. Tina Binderup
#140 Serotonin expression in gastric neuroendocrine tumors and in foci of endocrine cell hyperplasia
Introduction: The most abundant neuroendocrine (NE) cell population of the human oxyntic mucosa is the enterochromaffin-like (ECL) cells, followed by ghrelin, somatostatin and serotonin cells, respectively. All types of ECL cell carcinoids (ECL-CCs) contain serotonin cells but in a varying frequency. Hitherto, only foci of ECL and ghrelin cell hyperplasia have been described in the peritumorous mucosa of types I and II ECL-CCs. It is established that hypergastrinaemia can cause ECL cell hyperplasia but it does not affect serotonin cells. The vesicular monoamine transporter 2 (VMAT 2) is used as an immunohistochemical marker for ECL cells.
Conference: 7th Annual ENETS Conference (2010)
Category: Basic
Presenting Author: MD, PhD Apostolos Tsolakis
Authors: Tsolakis A, Falkmer S, Grimelius L, ...
#141 Incidence of second primary tumors in patients with neuroendocrine tumors
Introduction: Based on epidemiological data from SEER 1950-1999, 22.4% cases of non-carcinoid second primary tumors have been described in patients diagnosed with neuroendocrine tumors. The incidence of this type of tumors varies, depending on the series assessed.
Conference: 7th Annual ENETS Conference (2010)
Category: Clinical
Presenting Author: MD Juan Manuel OConnor
Authors: Pesce V, OConnor J, Mendez G, Bestani C, ...
#362 Succinate Dehydrogenase (SDH) Complex Expression in Pancreatic Endocrine Tumours (PETs)
Introduction: Absence of SDH subunit D (SDHD) mutations were reported by Perren et al (Oncogene 2002) but loss of heterozigosity (LOH) was described in 29% of the PETs. Since SDHD gene may depict a form of genomic imprinting in neuroendocrine (NE) tissue, the reported LOH may drive activation of the hypoxia pathway. Taking advantage from the immunohistochemical (IHC) method for genetic triage we may deduce the mutational status of SDH subunits (A, B, C and D) based on IHC SDHB expression. These subunits are striking candidates as they are mutated in other NE neoplasias.
Conference:
Category: Basic
Presenting Author: Mr João Vinagre
Authors: Vinagre J, Preto J, Soares P, Lopes J M, ...
Keywords: PETs SDH LOH
#407 Co-existing Type-1 Gastric Neuroendocrine Tumors (NETs) and Adenocarcinoma in Autoimmune Associated Atrophic Gastritis
Introduction: Autoimmune gastritis (AIG) causes oxyntic gland atrophy. This condition is often associated with Type-1 gastric NET secondary to achlorhydria and hypergastrinemia. Similar to atrophic gastritis in non-autoimmune conditions, AIG is associated with intestinal metaplasia that could progress to glandular dysplasia.
Conference: 9th Annual ENETS Conference (2012)
Category: Clinical
Presenting Author: Laura Tang
Authors: Tang L, ...
#443 Neuroendocrine Carcinoma (NEC) and Composite Exocrine-Neuroendocrine Carcinoma (CENEC) of the Stomach: A Clinicopathological Review of 58 Cases
Introduction: NEC of the stomach is an uncommon tumor accounting for 0.5% of all gastric carcinomas and about 6% of gastric NETs. CENEC contain both areas of NEC and conventional carcinoma. The histological diagnosis is difficult.
Conference: 9th Annual ENETS Conference (2012)
Category: Clinical
Presenting Author: Vladimir Khomyakov