Management of portal annular pancreas during laparoscopic pancreaticoduodenectomy

Portal Annular Pancreas With Common Hepatic Artery Trajectory Abnormality: A Case Report and Review of the Literature

ABSTRACT

Portal annular pancreas (PAP) is a rare congenital pancreatic anomaly, in which the uncinate process of the pancreas fuses to the body of pancreas behind the portal vein. Here, we report a case of PAP with common hepatic arterial anomaly, which was identified during surgery. A 57-year-old man who had branch type intraductal papillary mucinous neoplasm in the head of the pancreas developed a nodule in the cystic lesion. We planned pylorus preserving pancreaticoduodenectomy. The common hepatic artery from the celiac artery passing behind the portal vein was revealed in preoperative examinations. During surgery, we discovered that the uncinate process of the pancreas was fused with the body of the pancreas behind the portal vein. We divided the pancreas at the anterior and posterior of the portal vein. The main pancreatic duct was present in the anterior pancreatic stump. We performed pancreaticojejunostomy in the anterior stump and closed the posterior stump by interrupted suture. Forty-four surgical cases of PAP have been reported in the English medical literature. There are few previous reports of PAP which involved an arterial anomaly. Clinicians should consider PAP preoperatively to ensure that the surgeon can appropriately plan pancreatic resection to avoid postoperative complications.

Portal Annular Pancreas (PAP): an Underestimated Devil in Pancreatic Surgery-Systematic Review of Literature and Case Report

INTRODUCTION

Portal annular pancreas (PAP) is an anatomic variation due to aberrant fusion of the ventral and dorsal pancreatic buds around the portal vein. In this article, we present a case report with a systematic review of literature of patients undergoing major pancreatic surgery with associated PAP. We also intend to discuss and suggest possible surgical strategies to minimise major postoperative complications.

METHODS

A systematic literature search was conducted using the terms "circumportal," "periportal," "pancreas," "annular pancreas," "portal annular pancreas" and "pancreas anomaly." All articles describing portal annular pancreas with surgical resection were included.

RESULTS

We identified a total of 53 patients of PAP from 29 articles, who underwent pancreatic resection with a median age of 65 years. POPF (postoperative pancreatic fistula) was demonstrated in 42.55% of patients and 34% had CR (clinically relevant)-POPF. Following pancreaticoduodenectomy, pancreatic stump was reconstructed in all patients with either pancreaticojejunostomy or pancreaticogastrostomy. Standard line of pancreatic transection, i.e., division of anteportal portion at the pancreatic neck and stapling of the retroportal process, resulted in 71% incidence of CR-POPF, whereas it was only 16% when extended resection was performed to achieve single pancreatic stump and 12.5% when retroportal portion was sutured or ligated. Amongst distal pancreatic resections, 66% had POPF and 33% developed CR-POPF.

CONCLUSION

It is of utmost importance for pancreatic surgeons to diligently look for and identify PAP in the preoperative imaging. Additional imaging in the form of MRCP helps to define abnormal pancreatic ductal anatomy. Surgeons need to be cognisant of pancreatic stump management in patients with PAP to reduce associated higher rates of POPF.