Duodenal polyps are a relatively rare entity with a reported incidence of 0.3%-4.6%.1 There are three major types of duodenal adenomas: sporadic, nonampullary duodenal adenomas (SNDAs), adenomas in familial adenomatous polyposis syndrome, and ampullary adenomas. It is important to distinguish between the different types of duodenal polyps as the management may differ depending on the etiology.
SNDAs constitute <10% of all duodenal polyps, most commonly located in the second portion of the duodenum, and up to 85% have been shown to have malignant transformation over time.2 Most of the studies of SNDAs are small series, and there are no consensus guidelines for management. Villous features increase malignancy risk, thus resection of SNDAs is advised.3-7 It has also been shown that 72% of patients with SNDAs also have colon polyps,8 and therefore these patients should be up to date on colonoscopy screening.
Ampullary adenomas are less common, but up to half may be associated with familial adenomatous polyposis (FAP), and some may be surveyed.9 However, those that are larger than 10 mm or have villous features may raise concern for malignancy with up to half harboring small foci of adenocarcinoma.10,11 These require ERCP with ampullectomy. For the purposes of this paper, we will focus on endoscopic resection of SNDAs and ampullary adenomas.
Endoscopic mucosal resection (EMR) of duodenal polyps can be technically challenging. There are considerations specific to the duodenum: thin muscle layer, increased motility, and significant vascular supply including two major arterial supplies – the gastroduodenal artery from the celiac branch and the inferior pancreaticoduodenal artery from the superior mesenteric artery. These factors may explain higher reported rates of perforation and bleeding compared to colon EMR.