Portal annular pancreas in chronic pancreatitis: technical challenges in surgical management

Introduction Portal annular pancreas (PAP) is a rare anatomical variant characterized by abnormal fusion of pancreatic tissue between the uncinate process and the body of the pancreas encircling the portal vein. Although the technique of resection in pancreaticoduodenectomy has been described previously, in chronic pancreatitis, drainage procedures may also be required, rendering access to the retroportal segment of the portal annular pancreas technically challenging. In this study, we outline various management strategies based on the type of PAP and the involvement of the retroportal pancreatic duct. Methods This is a retrospective review of all patients diagnosed with chronic pancreatitis and PAP between January 2006 and September 2025. Information on patient demographics, the type of PAP, and treatment approaches was collected from electronic medical records and also by reviewing the cross-sectional imaging results of patients. Results Five patients were identified with both chronic pancreatitis and PAP and were classified under three categories: one with type 1, one with type 2, and three with type 3 PAP. Three patients underwent surgery: one patient presented with obstructive jaundice and therefore underwent an extended pancreaticoduodenectomy beyond the splenic artery to excise the retroportal pancreas; one patient underwent a Frey's procedure, as the duct of the retroportal pancreas was not involved; and one patient required a duodenum-preserving extended resection, including subtotal excision of the head of pancreas with PAP and pancreatojejunostomy, due to the retroportal course of the main pancreatic duct. Conclusions This study presents the first reported single-center limited case series describing the management of chronic pancreatitis associated with PAP. A tailored surgical approach was shown to be safe and effective, resulting in minimal postoperative morbidity and satisfactory pain relief.