Incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP‐NENs): An updated systematic review of population‐based reports from 2010 to 2023

Abstract There is a general perception that the incidence of neuroendocrine neoplasms (NENs) has been increasing. Nevertheless, reports of actual population‐based studies are scarce, and pertinent data from some geographical regions still need to be available. In this systematic literature review of population‐based studies, we aimed to evaluate the available data to provide updated figures on the incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP‐NENs). Guided by the PRISMA 2020 statement reporting items for systematic reviews, this study conducted a systematic search using Ovid in the bibliographic databases Embase, Medline, and Web of Science Core Collection. Only incidence‐reporting studies were included. In total, 847 articles were identified, and through a strict evaluation process using predefined inclusion and exclusion criteria, we found 19 papers that reported the general incidence of GEP‐NENs from all sites. In addition, we considered another 15 papers that focused on the epidemiologic aspects of single‐organ studies. While the incidence rates of GEP‐NEN vary across similar countries, the general incidence of GEP‐NEN has been increasing worldwide in recent decades. The incidence of GEP‐NENs has increased worldwide over the last two decades, and reliable figures from new regions add to this pattern. Nevertheless, variations in the classification, grading, and reporting of GEP‐NENs in various studies make direct comparisons difficult.