Controversies in NEN: An ENETS position statement on the endoscopic management of localised gastric, duodenal and rectal neuroendocrine neoplasms.

Gastric, duodenal and rectal neuroendocrine tumours (NETs) are increasingly detected due to advances in endoscopic imaging. While international guidelines provide criteria for endoscopic management, several aspects remain controversial due to limited high-quality evidence. This position paper, developed by an expert panel, aims to clarify these unresolved issues and provide consensus-based recommendations. The primary objective of this position paper is to critically analyse and address key controversies in the endoscopic management of gastro-duodenal-rectal NETs. These include the optimal selection of endoscopic resection techniques, the significance of R1 resections, pathological assessment and surveillance strategies. Special attention is given to site-specific challenges, including the role of Ki-67 in type 1 gastric NETs, the management of multiple gastric lesions, the feasibility of endoscopic resection for type 3 gastric NETs and the limitations of advanced endoscopic techniques in the duodenum. This position paper was developed using an Expert Panel Consensus methodology. Topics were identified during the 2024 ENETS Advisory Board meeting and addressed through a structured literature review. Evidence was critically appraised, and expert discussions were conducted to identify key points. By reviewing controversial aspects of endoscopic management, this position paper will provide practical guidance to optimise decision-making and improve outcomes for patients with gastro-duodenal-rectal NETs. Multidisciplinary evaluation remains crucial to tailoring treatment strategies based on tumour characteristics, patient factors and procedural risks.