Abstract library

22 results for "Osmar Martins Cruz Jr.".
#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
#2965 Molecular Signature of Rectal Neuroendocrine Neoplasia
Introduction: Rectal neuroendocrine tumors are rare neuroendocrine neoplasias (NEN). Little is known about prevalence and type of somatostatin receptor subtypes (sstr) expression and somatic mutations in relation to long-term clinical outcome.
Conference: 17th Annual ENETS Conference 2020 (2020)
Category: Basic Science - Genetics, epigenetics, miRNAs, Omics
Presenting Author: Dr. Nicole Unger
Authors: Unger N, Theurer S, Herold T, Weber F, ...
#271 A Novel Missense Mutation of the TMEM127 Gene that Leads to Pheochromocytoma Phenotype
Introduction: Recently, truncating germline mutations in TMEM127 gene have been identified in 30% of familial cases of adrenal pheochromocytoma (PHEO) and in 3% of apparently sporadic cases.
Conference: 8th Annual ENETS Conference (2011)
Category: Basic
Presenting Author: Rita Domingues
#273 The Succinate Dehydrogenase Genetic Testing in Patients with Extra-adrenal Paragangliomas: The Portuguese Cancer Center (Lisboa) Experience
Introduction: Extra-adrenal paragangliomas (PGLs) occur as sporadic or familial entities, the latter mostly in association with germline mutations of the SDHB, SDHC or SDHD genes.
Conference: 8th Annual ENETS Conference (2011)
Category: Basic
Presenting Author: Rita Domingues
#324 Well-differentiated Pancreatic Neuroendocrine Tumor of Uncertain Behavior: A Case Report
Introduction: A small number of Pancreatic Endocrine Tumors (PET) are well-differentiated tumors(WDET) showing benign or uncertain behavior. Prognosis mainly depends on the presence/absence of liver/bone metastasis.
Conference: 8th Annual ENETS Conference (2011)
Category: Clinical
Presenting Author: Dr. Joana Couto
#338 Pancreatic Endocrine Tumors: TNM staging and WHO Grading Relation with Prognosis
Introduction: Pancreatic endocrine tumors (PETs) are heterogeneous, rare neoplasms (large experience is unlikely). Prognostic stratification based on TNM staging and WHO grading is still under debate.
Conference: 8th Annual ENETS Conference (2011)
Category: Clinical
Presenting Author: Dra. Raquel G. Martins
#406 YF476, a Gastrin Receptor Antagonist, Causes Regression of Tumors and Normalizes Serum Chromogranin A in Patients with Type 1 Gastric Carcinoids
Introduction: Chronic atrophic gastritis (CAG) results in achlorhydria, hypergastrinemia and, in some patients, gastric carcinoids (type 1 GCs). Type 1 GCs may become malignant and metastasize. Current treatments of type 1 GCs, such as polypectomy, somatostatin analogues and antrectomy, have their disadvantages. YF476 – a potent, selective, orally active and well-tolerated gastrin receptor antagonist in pre-clinical studies – prevented, as well as reduced, the number and size of gastric carcinoids and carcinomas in rodent models.
Conference: 9th Annual ENETS Conference (2012)
Category: Clinical
Presenting Author: Reidar Fossmark
#410 Pancreatic Neuroendocrine Tumors: Retrospective Analysis Of 44 Cases
Introduction: Neuroendocrine tumors (NETs) are heterogeneous neoplasms. Pancreatic NETs (pNETs) have a broad spectrum of features. Bioamines and peptides production distinguish functional from nonfunctional tumors.
Conference: 9th Annual ENETS Conference (2012)
Category: Clinical
Presenting Author: Mr. Pedro Marques
#612 Serotonin in Blood: Assessment of its Origin by Concomitant Determination of β-Thromboglobulin (platelets) and Chromogranin A (enterochromaffin cells)
Introduction: Serotonin is produced in enterochromaffin (EC) cells, taken up and stored in platelets and released during platelet activation. Measurement of platelet-poor plasma serotonin is difficult, mainly due to platelet activation during blood sampling.
Conference: 10th Annual ENETS Conference 2013 (2013)
Category: Biomarkers
Presenting Author: Øyvind Hauso
#734 Non-Functioning Neuroendocrine Pancreatic Neoplasia as an Incidental Finding–Surgery?
Introduction: The incidence of pancreatic non-functioning neuroendocrine neoplasms (PNF-NENs) has been increasing, mainly due to small incidentalomas. Pancreatic surgery complications are still responsible for significant morbidity.
Conference: 10th Annual ENETS Conference 2013 (2013)
Category: Surgical treatment
Presenting Author: Dr. Joana Couto