Portal Annular Pancreas: Case Report of a Rare Anomaly

Portal annular pancreas is a rare congenital anomaly in which the portal vein and/or the splenoportal confluence are completely encircled by aberrant pancreatic parenchyma. It is an asymptomatic condition and is usually an incidental finding. It is, however, important to a surgeon because the postoperative pancreatic fistula (POPF) rates following pancreatic resection are higher in patients with this anomaly. A 47-year-old male presented with features of obstructive jaundice. He was diagnosed to have periampullary carcinoma, and pancreatoduodenectomy was planned. During surgery, uncinate process was seen extending posterior to the portal vein and was communicating with the body of pancreas to the left of the portal vein. After transection, there were two pancreatic stumps. The pancreatic duct was identified in the stump anterior to the portal vein. No duct was present in the posterior pancreatic stump. We closed the posterior pancreatic stump with interrupted polypropylene sutures and performed a duct to mucosa pancreaticojejunostomy in the anterior stump. On reviewing the preoperative computed tomography (CT) scan, we were able to identify the pancreatic tissue encasing the portal vein superior to the splenic vein. Circumportal pancreas is classified based on the orientation of pancreatic duct to the portal vein and the relationship of the aberrant pancreatic tissue with the splenoportal confluence. Following pancreatoduodenectomy, the surgeon has to manage two pancreatic stumps, one anterior and the other posterior to the portal vein. No standardised technique has been described for management of the pancreatic stumps. Every surgeon planning pancreatic surgery should be aware of this rare anomaly, and look for the same in the preoperative CT scan so that appropriate plan can be made regarding the type of pancreatic anastomosis.