This ESGE Guideline provides a clear summary of the evidence base regarding endoscopic treatment of superficial nonampullary duodenal tumors, with recommendations for routine practice. A companion Guideline has provided guidance on ampullary tumors.

In 2016, ESGE published a set of research priorities for gastrointestinal endoscopy, but endoscopic practice is rapidly changing owing to new endoscopic innovations and research. In this article, ESGE detail their latest review of the literature and identify the areas for which recent research publications have already provided answers and those that have questions still to answer.