Annular pancreas associated with duodenal carcinoma

Abstract

Annular pancreas (AP) is a rare congenital anomaly. Coexisting malignancy has been reported only in a few cases. We report what is, to the best of our knowledge, the first case in the English literature of duodenal adenocarcinoma in a patient with AP. In a 55-year old woman with duodenal outlet stenosis magnetic resonance cholangiopancreatography showed an aberrant pancreatic duct encircling the duodenum. Duodenojejunostomy was performed. Eight weeks later she presented with painless jaundice. Duodenopancreatectomy revealed a duodenal adenocarcinoma, surrounded by an incomplete AP. Thus, co-existent malignancy with AP can be present without obstructive jaundice and without being visible through preoperative diagnostics.

Figure 1

Multislice computed tomography. A fluid filled stomach and enlargement of the pancreatic head (arrow) are detected, which encircles the second segment of the duodenum (dotted arrow).

Figure 2

T2 weighted magnetic resonance cholangiopancreatography images depict the aberrant pancreatic duct, which encircles the duodenum and connects with the main pancreatic duct (arrows).

Figure 3

During surgery, a massively distended and elongated first segment (left arrow) and a conic stenosis of the second segment of the duodenum were observed due to the annular pancreas (right arrow).

Figure 4

Eight weeks later, T1 w post contrast axial MR shows dilatation of the common bile duct.

Figure 5

Cross sectional view showing the tumor within the duodenum (asterisk). The duodenum is surrounded by the incomplete annular pancreas (arrows).