Korean J Gastroenterol.  2012 Jul;60(1):52-55. 10.4166/kjg.2012.60.1.52.

Two Cases of Portal Annular Pancreas

• Jang JY
• Chung YE
• Kang CM
• Choi SH
• Hwang HK
• Lee WJ

• KMID: 1718467
• DOI: http://doi.org/10.4166/kjg.2012.60.1.52

Abstract

Portal annular pancreas is one of the pancreatic fusion anomalies in which the uncinate process of the pancreas extends to fuse with the dorsal pancreas by encircling the portal vein or superior mesenteric vein. We report two consecutive patients with portal annular pancreas. The first case is a 71-year-old male patient who underwent a pancreaticoduodenectomy for intraductal papillary mucinous neoplasm in the head of pancreas. His preoperative computed tomography scan showed the suprasplenic type portal annular pancreas. The second case is a 74-year-old female patient who underwent a laparoscopic anterior radical antegrade modular pancreatosplenectomy (RAMPS) for pancreatic body cancer. In operative finding, portal confluence (superior mesenteric vein-splenic vein-portal vein) was encased with the uncinate process of pancreas in both cases. Therefore, they required pancreatic division at the pancreatic neck portion twice. During the postoperative period, grade B and A, respectively, postoperative pancreatic fistulas occurred and were controlled by conservative management. Surgeons need to know about this rare pancreatic condition prior to surgical intervention to avoid complications, and to provide patients with well-designed, case-specific pancreatic surgery.

Keyword

Pancreas; Annular pancreas; Anomaly

MeSH Terms

Adenocarcinoma, Mucinous/diagnosis/surgery
Aged
Female
Humans
Male
Mesenteric Veins/radiography
Pancreas/abnormalities
Pancreatic Diseases/*diagnosis/therapy
Pancreatic Fistula/etiology
Pancreatic Neoplasms/diagnosis/surgery
Pancreaticoduodenectomy/adverse effects
Portal Vein/radiography
Splenic Vein/radiography
Tomography, X-Ray Computed

Figure

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  Fig. 1 Portal annular pancreas noted in porcine pancreas. The pancreas encased the superior mesenteric vein (SMV) and the portal vein confluence (white arrow).

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  Fig. 2 Case 1 patient with portal annular pancreas for pancreaticoduodenectomy. The uncinate process of the pancreas encased PV (long white arrow) (A). The multilocular cystic lesion in the uncinate process (arrow head of picture in picture) showed suspicious invasive nature with diffuse soft tissue infiltration around superior mesenteric artery and celiac axis (A). The nP area was dissected from the SMV-PV-SV confluence (B). The uncinate process of the pancreas fused with the dP was divided with endo-GIA (C). The operative field after delivery of the surgical specimen, gastroduodenal artery stump (short white arrow), and division line of uncinate process pancreas (long white arrow) (D). nP, pancreatic neck; SMV, superior mesenteric vein; PV, portal vein; dP, dorsal pancreas; CHA, common hepatic arery; BD, bile duct.

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  Fig. 3 Preoperative MRI showed an ill-defined mass with multilocular cystic lesion in the body of the pancreas (arrow), suggesting intraductal papillary mucinous neoplasm (IPMN) accompanied by pancreatic cancer or malignant IPMN of branch duct type.

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  Fig. 4 Case 2 patient with portal annular pancreas for laparoscopic anterior RAMPS. The portal annular pancreas was noted (A). Pancreatic neck dissection for the division. Note the 'pancreatic bridge' between the uncinate process and the doral pancreas (long white arrow) (B). After dividing the pancreatic neck portion, pancreatic fusion was more clearly identified (long white arrow). The SV was also divided at the junction to the SMV (narrow white arrow) (C). Operative field view (D). Besides division of the pancreatic neck portion, an additional pancreatic division line was noted (short white arrow). The origin of the splenic artery (multiple short white arrows) and SV (narrow white arrow) could be observed. SMV, superior mesenteric vein; SV, splenic vein; CHA, common hepatic artery; PV, portal vein; pP, proximal pancreas; P, pancreas; RAMPS, radical antegrade modular pancreatosplenectomy.

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