Concurrent Invasive Ductal Carcinoma and Pancreatic Intraepithelial Neoplasia in Duodenal Heterotopic Pancreas: A Case Report

Abstract

Heterotopic pancreatic (HP) tissue is defined as the presence of pancreatic tissue outside of its usual site with no vascular or anatomic association with the normal pancreas. This is most commonly found in the stomach, duodenum, and proximal jejunum. Most HP findings are incidental. Yet, they can occasionally produce symptoms such as bleeding, abdominal pain, and gastrointestinal obstruction symptoms. HP tissues can also become malignant. The following report details a rare case of a 77-year-old man with concurrent invasive ductal carcinoma and low-grade pancreatic intraepithelial neoplasia involving an HP tissue located at the duodenum.

Keywords: Adenocarcinoma; Ductal Carcinoma; Duodenum; Neoplasms; Oman; Pancreas.

Figure 1

A gross image of the excised submucosal ectopic pancreatic foci. The red arrow indicates where it was attached to the duodenal wall. The cut surface displays a well-defined homogenous solid lesion.

Figure 2

(a) A microscopic image of the ectopic submucosal pancreatic tissue composed of acini and ducts (black arrow) with a low-grade pancreatic intraepithelial neoplasia (LG-PanIN) lesion (red arrow) and overlying unremarkable duodenal mucosa (green arrow), hematoxylin and eosin (H&E) stain, magnification = 4 ×. (b) A higher magnification of the ectopic foci exhibiting LG-PanIN lesion (red arrow), H&E stain, magnification = 10 ×.

Figure 3

(a) The pancreatic ductal adenocarcinoma in the native pancreas expressing p53 immunohistochemistry stain with variable nuclear expression (stained brown), hematoxylin and eosin (H&E) stain, magnification = 10 ×. (b) The pancreatic intraepithelial neoplasia involving the ectopic pancreas shows complete loss of p53 nuclear stain (red arrow), H&E stain, magnification = 10 ×.