Clinicopathological features of superficial non-ampurally duodenal epithelial tumor; gastric phenotype of histology correlates to higher malignant potency

Background Superficial non-ampullary duodenal epithelial tumors (SNADETs) are relatively rare, but they are now being detected more frequently due to advances in endoscopic technology. Nevertheless, the pathological nature of SNADETs remains unclear and a management strategy for these tumors has not been established. Methods To elucidate the clinicopathological features, we conducted a retrospective analysis of 138 endoscopically resected SNADETs. Lesions were classified into two groups by histological grade according to the Vienna classification: category 3 (71 lesions, 51.4%) and category 4/5 (67 lesions, 48.6%). Results Compared with category 3 lesions, category 4/5 lesions were significantly more common in elderly patients ( p