Abstract Library

#3796 The effect of pseudohypoxia on the immune microenvironment of pancreatic neuroendocrine neoplasms (PanNEN)

Introduction: Pancreatic neuroendocrine tumors may develop sporadically or as part of an inherited disease, such as von Hippel-Lindau (VHL). VHL disease is caused by a germline pathogenic variant in the VHL gene encoding VHL protein (pVHL). Hypoxia inducible factor (HIF) is responsible for cellular oxygen supply. Its degradation is mediated in normoxic states via ubiquitination and inhibited by pVHL. Hence, pVHL deficiency leads to pseudohypoxia due to HIF overexpression. Several studies suggested immunomodulatory role for HIF in kidney cancer.

Conference:

Presenting Author:

Authors: Solomon Chmelnik A, Telerman A, Tirosh A,

Keywords: Pancreatic neuroendocrine tumor, VHL, DNA methylation, Immune cells, PD-L1,

#3790 Pancreatic neuroendocrine tumors (pNETs) in French VHL mutation carriers – A nationwide retrospective study with genotype-phenotype correlations

Introduction: Von Hippel-Lindau disease (VHL) is a rare inheritable syndrome predisposing to pancreatic neuroendocrine tumors (pNETs). The natural history of VHL-related pNETs is ill-known.

Conference:

Presenting Author:

Authors: Muller M, Hammel P, Sauvanet A, Couvelard A, Vullierme M,

Keywords: hereditary neoplastic syndrome, von Hippel-Lindau disease, VHL gene, pancreatic neuroendocrine tumor,

#1854 VHL Genotype Is Associated with Pancreatic Neuroendocrine Tumors (PNETs) Phenotype in Patients with Von Hippel-Lindau Disease (VHLD)

Introduction: 8-20% of patients with VHLD develop PNETs. However, there are no markers for PNETs progression in VHLD patients. The type of mutation in VHL gene is associated with clinical phenotype of VHLD.

Conference: 14th Annual ENETSConcerence (2017)

Presenting Author: Tirosh A

Authors: Tirosh A, Shell J, Keutgen X, Sadowski S, Green P,

Keywords: VHL, mutation, prognosis,

#22 A Case Illustrative of Phenotypic Heterogeneity and Challenges in the Management of Paraganglioma

Introduction: Paragangliomas (PGLs) are extra-adrenal, usually benign, highly vascularized tumors that originate from neural-crest-derived chromaffin cells. These tumors are subdivided as either sympathetic or parasympathetic, depending on their location and catecholamine production. Sympathetic PGLs are situated along the abdominal sympathetic trunk and usually produce catecholamines, whereas parasympathetic PGLs are located in the head and neck, and these usually do not produce catecholamines. PGLs may present as sporadic or inherited tumor syndrome, including MEN 2, with RET germline mutations, von Hippel-Lindau (VHL) disease due to germline mutations in VHL gene, and pheochromocytoma-PGL syndrome. The latter is frequently a hereditary condition and is caused by germline mutations in the SDHB, SDHC, or SDHC genes. Patients with familial PGLs may present at a younger age, often as multifocal tumors, with an increased risk of recurrence and a higher frequency of malignancy in those with SDHB mutations. SDH mutations induce angiogenesis and tumorogenesis through the inhibition of hypoxia-inducible factors (HIF)-propyl hyroxylase. A younger age at onset, malignancy, and a positive family history are clinical parameters of high specificity, but low sensitivity for diagnosis. Genetic analysis for mutations in SDH genes for the patient and family members, and surveillance for the affected patient and family members, are necessary where there are no clear clinical or family indicators for the syndrome. We present a case of a large abdominal malignant PGL in a 20-year-old pt. that went on without clinical detection for at least three years.

Conference: 7th Annual ENETSConcerence (2010)

Presenting Author: Ahmed D

Authors: Ahmed D, Amin D, Al Faraj D, Al Qahtani D,

Keywords: paraganglioma, succinate dehydrogenase B mutation, abdominal tumor, malignant/metastatic paraganglioma, serum urinary, catecholamines,