Duodenal Adenocarcinoma Arising from Brunner’s Glands, A Rare Case Report

Abstract Introduction/Objective Malignancies arising from the Brunner’s glands in duodenum are exceedingly rare with very few cases reported in the literature. Here, we reported a case of duodenal adenocarcinoma of Brunner’s gland origin that obstructed duodenum and extended to involve the pancreatic head. Methods/Case Report A 48-year-old woman came to the Emergency Department of our hospital with epigastric and right upper quadrant abdominal pain. CT imaging demonstrated a heterogeneously enhancing 8.4 x 5.4 x 6 cm mass involving the duodenal lumen, wall, and pancreatic head. An endoscopic ultrasound showed a large fungating, infiltrative, and ulcerative mass in the second portion of the duodenum distal to the ampulla but not involving it. The pancreatic and common bile ducts were uninvolved. Her endoscopic ultrasound biopsy was positive for adenocarcinoma. CA19-9 levels were normal. The patient received chemotherapy with subsequent Whipple procedure. Gross examination revealed an exophytic, tan-white mass with the epicenter in the duodenal wall obstructing the duodenal lumen and extending to involve the pancreatic head inferiorly. The mass was predominantly solid with a few small mucus cysts. Light microscopy demonstrated moderately differentiated adenocarcinoma with prominent necrosis and inflammation. There are intestinal-type, gastric-type and indeterminate types of epithelia in the carcinoma. There are areas in the duodenal wall where a continuous transition from benign Brunner’s glands to dysplastic glands and then to adenocarcinoma is present. Neither adenoma in the overlying duodenal mucosa nor abnormalities in the pancreatic parenchyma is observed. Immunohistochemical stains showed that the neoplastic cells are positive for CAM 5.2, AE1/AE3, and CK7, while only patchy positivity with CK20 and CDX2. Taken together, a diagnosis of duodenal adenocarcinoma arising from Brunner’s glands was rendered. Results (if a Case Study enter NA) N/A Conclusion More cases are needed in order to establish standard treatment guidelines and determine prognostic factors.