Duodenal duplication cyst: a rare cause of recurrent pancreatitis.

We report the case of a 54-year-old man with a medical history of recurrent pancreatitis who was referred to our department for a novel episode of epigastric pain. A blood test confirmed the diagnosis of acute pancreatitis, and a biliary origin was suspected because of abnormal liver test results and dilatation of the biliary ducts as shown by US. A CT scan confirmed the bile duct dilatation and showed a voluminous cystic lesion of 40 × 30 mm developed from the duodenal wall (Fig. 1). Upper GI endoscopy identified a submucosal pedunculated lesion likely originating from the papilla area and completely obstructing its lumen. The cystic characteristics of the lesion were confirmed by EUS, but neither the typical double-wall sign nor the communication sign between the cyst and the main bile duct were observed. These findings were compatible with 2 hypotheses: a duodenal duplication cyst (DDC) or a type III choledochocele. Abdominal MRI with 3-dimensional construction was not able to discriminate between the 2 diagnoses. Because the patient was symptomatic and these lesions are associated with malignant potential, an endoscopic resection was proposed (Video 1, available online at www.VideoGIE.org).1, 2

Figure 1

Multimodal morphologic evaluation. A, Contrast-enhanced CT coronal image showing dilatation of main duct and cystic lesion obstructing the duodenum (white arrows show main duct and cystic lesion). B, MRCP coronal image showing cystic lesion obstructing the lumen (white arrows show main duct and cystic lesion). C, EUS view of lesion measuring 38 (D1) × 32 (D2) mm. The cyst contains a heterogeneous material compatible with sludge. D, MRCP 3-dimensional construction showing a regular cholangiopancreatogram without direct connection to the cyst.

A progressive debulking piecemeal resection was initially proposed. After several resections, the cyst was clearly identified as arising from the papilla. Consequently, a papillectomy with biliopancreatic stent placement also was performed. No adverse events occurred. Endoscopic evaluation 1 month after the procedure showed a completely re-epithelialized papilla. Histologic analysis confirmed the diagnosis of benign DDC with typical features such as intestinal mucosal layer on both sides of the lesion, separated by a submucosal layer containing 2 muscularis mucosae (Fig. 2).

Figure 2

Endoscopic and histologic results after resection. A, Macroscopic view of first resection showing digestive mucosa covering both sides of the lesion. B, Endoscopic view at 1 month identifying complete re-epithelialization of the resected area. Both pancreatic and biliary orifices are easily identified. C, D, Histologic analysis of duodenal duplication cyst after hematoxylin-eosin-saffron staining, at different levels of magnification, showing typical duodenal mucosa lining both lumina, separated by a submucosal layer and containing smooth muscle.

Duodenal duplication cysts are a rare congenital abnormality that can cause digestive symptoms. It has an estimated prevalence of less than 1 per 100,000 persons. Usually diagnosed during childhood, it can remain asymptomatic until adulthood. The clinical manifestations of a DDC are numerous, including abdominal pain, nausea and vomiting, pancreatitis, cholestasis or hepatitis, and GI bleeding. In adults, the most frequent presentation is acute pancreatitis.

The diagnosis of duodenal duplication cysts can be challenging. The main differential diagnosis of a DDC is the type III choledochal cyst (choledochocele), according to the classification by Todani et al. The DDCs represent 5% of all GI duplications and have a cystic structure bulging into the duodenal lumen and developed distally from the ampulla of Vater. A cyst–pancreaticobiliary duct connection is identified in almost 29% of cases. Therefore, the cyst can be filled with duodenal secretions, biliary secretions, or both. By contrast, choledochoceles have a cystic structure originating from the main bile duct and protruding proximally from the papilla. The principal distinguishing feature between these 2 entities is their histologic characteristic: DDCs are covered both inside and out with duodenal mucosa containing a distinct layer of smooth muscle.

Both duodenal duplication cysts and choledochoceles are associated with an evolution to malignancy,1, 2 justifying their resection. Endoscopic resection is minimally invasive and has been proposed as an alternative in selected patients. Antaki et al reported a series of 7 successful endoscopic resections for benign symptomatic DDCs. The basic principle in all cases was a marsupialization of the cyst to allow free drainage into the duodenal lumen. There were no major events and no local recurrence after 7 months of follow-up. Several case reports have also demonstrated the success of this innovative approach, indicating that endoscopic resection is a safe and effective technique in selected cases.8, 9

Disclosure

All authors disclosed no financial relationships relevant to this publication.