JNETS clinical practice guidelines for gastroenteropancreatic neuroendocrine neoplasms: diagnosis, treatment, and follow-up: a synopsis

Abstract

Neuroendocrine neoplasms (NENs) are rare neoplasms that occur in various organs and present with diverse clinical manifestations. Pathological classification is important in the diagnosis of NENs. Treatment strategies must be selected according to the status of differentiation and malignancy by accurately determining whether the neoplasm is functioning or nonfunctioning, degree of disease progression, and presence of metastasis. The newly revised Clinical Practice Guidelines for Gastroenteropancreatic Neuroendocrine Neoplasms (GEP-NENs) comprises 5 chapters—diagnosis, pathology, surgical treatment, medical and multidisciplinary treatment, and multiple endocrine neoplasia type 1 (MEN1)/von Hippel–Lindau (VHL) disease—and includes 51 clinical questions and 19 columns. These guidelines aim to provide direction and practical clinical content for the management of GEP-NEN preferentially based on clinically useful reports. These revised guidelines also refer to the new concept of “neuroendocrine tumor” (NET) grade 3, which is based on the 2017 and 2019 WHO criteria; this includes health insurance coverage of somatostatin receptor scintigraphy for NEN, everolimus for lung and gastrointestinal NET, and lanreotide for GEP-NET. The guidelines also newly refer to the diagnosis, treatment, and surveillance of NEN associated with VHL disease and MEN1. The accuracy of these guidelines has been improved by examining and adopting new evidence obtained after the first edition was published.

Ampullary Large-Cell Neuroendocrine Carcinoma, a Diagnostic Challenge of a Rare Aggressive Neoplasm: A Case Report and Literature Review

“…Further imaging is necessary to rule out distant metastases [ 46 ]. Although GEP-NETs are slow-growing and have low glycolytic activity, FDG-PET scan might aid in revealing distant metastases and recurrent lesions of highly proliferative tumors, such as NECs [ 4 , 47 ].…”

“…Since NETs of the Vater’s ampulla and their metastases often express somatostatin receptors, somatostatin receptor scan (SRS) can detect them with an 86% sensitivity [ 8 , 43 ]. However, although somatostatin receptors are often expressed in NET G3, SRS cannot detect the usually somatostatin-receptor-negative NECs [ 46 ]. In addition, mutations in the P53 tumor-suppressor gene and deletion of the Rb gene are often present in NECs, indicating an extremely malignant tumor, thus making those markers useful for the differential diagnosis between NET G3 and NECs [ 16 ].…”

Case reports: chemoradiotherapy for locally advanced neuroendocrine carcinoma of the gallbladder

“…According to a European clinical guideline, cisplatin/etoposide or carboplatin/etoposide is recommended as the standard first-line systemic chemotherapy [10]. In addition, a Japanese clinical guideline recommended platinum-doublet chemotherapy for unresectable and metastatic gastroenteropancreatic (GEP)-NEC [11]. However, there is no established second-line therapy for GEP-NEC.…”

New insights in diagnosis and treatment of gastroenteropancreatic neuroendocrine neoplasms

“…GEN-NENs are relatively rare (1.0%-1.5% of all GEP neoplasms, 6.98 and 0.4 new cases per year per 100000 individuals in the United States for GEP-NETs and GEP-NECs, respectively)[ 4 - 7 ], although their incidence has significantly increased in the past 3 decades, largely due to the improved awareness and detection rate. The majority (> 95%) of GEP-NENs are sporadic, although some (approximately 5%) could be part of syndromic presentations, including multiple endocrine neoplasm type 1 (MEN1), neurofibromatosis type 1 (NF1), and von Hippel–Lindau syndrome (VHL)[ 1 - 4 ].…”