Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Endosc. May 16, 2022; 14(5): 267-290
Published online May 16, 2022. doi: 10.4253/wjge.v14.i5.267
Current updates and future directions in diagnosis and management of gastroenteropancreatic neuroendocrine neoplasms
Andrew Canakis, Linda S Lee
Andrew Canakis, Division of Gastroenterology and Hepatology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
Linda S Lee, Division of Gastroenterology Hepatology and Endoscopy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, United States
Author contributions: Canakis A drafted the manuscript and approved the final version of the manuscript; Lee LS drafted, revised, and approved the final version of the manuscript.
Conflict-of-interest statement: Each author listed has no potential conflicts (financial, professional, or personal) that are relevant to the content presented in this manuscript.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Linda S Lee, MD, Associate Professor, Director, Division of Gastroenterology Hepatology and Endoscopy, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St, Boston, MA 02115, United States.
Received: December 31, 2021
Peer-review started: December 31, 2021
First decision: January 23, 2022
Revised: February 14, 2022
Accepted: April 21, 2022
Article in press: April 21, 2022
Published online: May 16, 2022
Processing time: 136 Days and 9.6 Hours

Gastroenteropancreatic neuroendocrine neoplasms are a heterogenous group of rare neoplasms that are increasingly being discovered, often incidentally, throughout the gastrointestinal tract with varying degrees of activity and malignant potential. Confusing nomenclature has added to the complexity of managing these lesions. The term carcinoid tumor and embryonic classification have been replaced with gastroenteropancreatic neuroendocrine neoplasm, which includes gastrointestinal neuroendocrine and pancreatic neuroendocrine neoplasms. A comprehensive multidisciplinary approach is important for clinicians to diagnose, stage and manage these lesions. While histological diagnosis is the gold standard, recent advancements in endoscopy, conventional imaging, functional imaging, and serum biomarkers complement histology for tailoring specific treatment options. In light of developing technology, our review sets out to characterize diagnostic and therapeutic advancements for managing gastroenteropancreatic neuroendocrine tumors, including innovations in radiolabeled peptide imaging, circulating biomarkers, and endoscopic treatment approaches adapted to different locations throughout the gastrointestinal system.

Keywords: Gastroenteropancreatic neuroendocrine neoplasms, Neuroendocrine tumors, Neuroendocrine carcinoma, Gastrointestinal, Pancreas, Small intestine

Core Tip: Diagnostic technology for neuroendocrine tumors continues to advance. Radiomics promises to enhance morphologic imaging. Gallium-68 DOTA-peptide positron emission tomography/computed tomography has replaced Octreoscan as the preferred functional imaging modality. Newer radiolabeled peptides may further improve detection. A novel liquid biopsy biomarker (NETest) has proven more accurate than chromogranin A in monitoring treatment response and predicting disease activity. Therapy has also progressed with treatment adapted based on the predicted behavior of the tumor. Advanced endoscopic resection techniques have revolutionized treatment. Preliminary evidence suggests endoscopic ultrasound guided radiofrequency ablation may prove useful in treating pancreatic lesions. Multimodality therapy continues to evolve for metastatic pancreatic tumors.