Current status of endoscopic diagnosis and treatment for superficial non-ampullary duodenal epithelial tumors.

Though superficial non-ampullary duodenal epithelial tumors (SNADETs) have been traditionally considered rare, there is a growing detection under the development and widespread of endoscopic techniques in recent times. Many case studies have revealed early manifestations of lesions through advanced endoscopic technology, however, because of the low incidence of duodenal tumors and challenges in diagnosing, the preoperative diagnosis criteria have not been established so far. In spite of this, recently the increasing detection rate of early duodenal epithelial lesions enhances the demand for minimally invasive treatment as well. The most suitable therapeutic endoscopic modality to remove duodenal lesions should be selected according to the size, location and histological invasive depth of duodenal lesions. Nevertheless, due to the special anatomical structure of the duodenum, the incidence of complications is much higher than in any other part of the digestive tract. To prevent these adverse events prophylactically, a few novel strategies have been applied effectively after resection. This review describes the current status of preoperative endoscopic diagnosis and endoscopic resection approaches, as well as countermeasures for avoiding procedure-related complications.