Pancreatic intraepithelial neoplasia in heterotopic pancreas: incidentally diagnosed on endoscopic mucosal resection of a duodenal polyp.

Heterotopic pancreas is the presence of pancreatic tissue outside its normal location. It can develop similar pathological conditions that develop in the normal pancreas, including adenocarcinoma and its precursor lesions. Due to the rarity of the condition, the diagnosis can be challenging, and treatment is not well established. ​We present a 47-year-old female patient referred for endoscopic resection of a 2 cm polyp in the second part of her duodenum. Complete endoscopic mucosal resection (EMR) was performed, with pathology revealing low-grade pancreatic intraepithelial neoplasia (PanIN) in heterotopic pancreatic tissue. To the best of our knowledge, this is the first case of heterotopic pancreas with low-grade PanIN in the duodenum to be incidentally diagnosed and treated with EMR. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.