LAUSR

Gangliocytic paraganglioma (GP), biologically similar to pheochromocytoma, is a rare tumor predominant in the second portion of the duodenum. GP is histologically composed of 3 types of cells: epithelioid endocrine cells, ganglion-like cells, and spindle-shaped cells. Although EUS-guided FNA is useful for preoperative diagnosis, small biopsy specimens make diagnosis difficult. In some cases, surgery has been performed for diagnosis. Here, we report a case in which endoscopic papillectomy (EP) was used as a diagnostic modality. Informed consent was obtained from the patient to publish his case. An asymptomatic 37-year-old man presented with a subepithelial tumor with ampullary involvement, expressing his desire to undergo endoscopic treatment. Histologic examination of a specimen from tunnel biopsy performed in the previous hospital revealed signs of neuroendocrine tumor. CT findings showed uneven contrast material within the tumor (Fig. 1A). Moreover, EUS revealed no infiltration of the duodenal muscle, bile duct, or pancreatic duct by the tumor (Fig. 1B). Thus, we presumed that the tumor was resectable by EP and could aid in establishing the histologic diagnosis and definitive treatment (Video 1, available online at www.VideoGIE.org).