Duodenal Duplication Cyst in adult male; An Extremely Rare Entity and a Diagnostic Pitfall leading to Whipple procedure

Abstract

Abstract Introduction/Objective Whipple procedure is a complex, invasive operation and has high morbidity and mortality. It is the most commonly indicated treatment for treating malignant tumors, however, it can be also used for benign entities as well including biliary stricture, chronic pancreatitis, choledochal cyst, inflammatory pseudotumour, and duodenal angiodysplasia. Methods/Case Report We report a case of a 50-year-old man who presented with symptoms of gastric outlet obstruction. Esophagogastroduodenoscopy and CT scan showed an obstruction at the level of the second part of the duodenum with proximal dilation. Subsequently, a Whipple procedure was performed based on high clinical suspicion of duodenal cancer. Gross examination revealed a unilocular thick walled cyst (4.2 cm) in the duodenum. Histopathologic examination showed a cyst lined by duodenal mucosa with thick smooth muscle wall and focal ectopic gastric tissue. This was finally diagnosed as a duodenal cyst consistent with duplication cyst. Results (if a Case Study enter NA) NA Conclusion Duplication cysts are rare congenital abnormality predominantly diagnosed in infancy and childhood. They are most commonly located in the distal ileum, followed by the esophagus and ileocecal region, and are extremely rare in duodenum. Differential diagnosis includes choledochocele, pancreatic pseudocyst, and cystic tumors of the pancreas, mesenteric cysts, and duodenal diverticulums. Treatment options include total excision, cystojejunostomy, and endoscopic marsupialization but occasionally may lead to more invasive measures such as the Whipple procedure. Although duodenal duplication cysts can have variable clinical presentation and radiological findings, making preoperative diagnosis very challenging, it is still pertinent to be aware of this entity for the optimal patient care.