Pancreaticobiliary maljunction (PBM) was first reported in the Japanese literature by Kozumi et al. in 1916 . In the English literature, Babbitt first reported three patients with an anomalous arrangement of the pancreaticobiliary ductal system in 1969 . PBM is a congenital anomaly in which the pancreatic and bile ducts join anatomically outside the duodenal wall. According to the Japanese clinical practice guidelines for pancreaticobiliary maljunction, PBM includes one type that is associated with bile duct dilatation (congenital biliary dilatation), and another without biliary dilatation . When the sphincter of Oddi contracts, pancreatic juice flows back into the common bile duct, causing chronic inflammation of the biliary tract. Both types of PBM are associated with a high incidence of biliary tract cancer. PBM without biliary dilatation often remains asymptomatic, even in adults. However, the reciprocal reflux of pancreatic juice and bile are remain persistent. Pancreatic enzymes, particularly phospholipase A2, are occasionally activated by contaminated bile, causing acute pancreatitis and chronic pancreatitis [5, 6]. Unlike biliary tract cancer, the relationship between PBM and pancreatic cancer remains unclear. Recently, Sato K et al. published a case report containing literature review of PBM and pancreatic cancer . In this report, pancreatic cancer associated with congenital biliary dilatation revealed that biliary tract cancer preceded the pancreatic cancer in all metachronous multiple cancer cases. Since there are few reports of distal pancreatectomy (DP) for patients with PBM [8, 9], postoperative course after DP is largely unknown. The risk of postoperative pancreatic fistula (POPF) appears to be considerably high in patients with PBM due to constantly activated pancreatic enzymes. In addition, endoscopic sphincterotomy was performed for common bile duct stones in this patient. Pancreatic trypsinogens are also activated by refluxed duodenal juice containing enterokinase .
PF is a frequent complication after DP and occurs in 5–40% of resected cases . Although few studies have evaluated risk factors for the development of clinically relevant POPF (CR-POPF) after DP, a recent meta-analysis reported that smoking and open DP were risk factors and that diabetes was protective factor of CR-POPF . Although linear stapler is usually used in laparoscopic DP, the impact of the pancreatic stump closure technique (staple vs. direct suture) on CR-POPF was similar. Recently, pancreatic thickness to main pancreatic duct diameter ratio greater than 8 (a wide pancreas with a narrow duct) was reported to be a significant predictable factor for CR-POPF after stapled DP. In the patient in this case, no well-known risk factors were identified.
Various technical and medical ingenuities have been used to reduce the incidence rate of CR-POPF. During laparoscopic DP, division of the pancreas at the neck significantly reduced CR-POPF compared to division at the body . Although simple biodegradable stapler reinforcement at the transection line did not reduce CR-POPF , application of fibrin glue followed by wrapping the polyglycolic acid (PGA) mesh around the remnant pancreatic stump significantly reduced the rate of CR-POPF . In medical intervention, a recent systematic review with meta-analysis of randomized controlled trials elucidated the usefulness of somatostatin analog in decreasing the risk for POPF after DP . However, applying the above-mentioned ingenuities could not prevent the incidence of POPF in our case.
Unfortunately, CR-POPF occurs after drain removal or drain migration away from the pancreatic stump, safety and efficacy of endoscopic transpapillary pancreatic duct stent placement have been reported . In our case, an intraoperatively placed drain remained near the pancreatic stump. The drainage fluid changed to yellowish in color with bile contamination on POD9, so we decided to perform additional internal drainage and separation of bile and pancreatic juice. Although endoscopic naso-pancreatic drainage (ENPD) is more effective than ERPD in achieving complete drainage of pancreatic juice, the remnant length of the pancreatic duct was not sufficient for stable placement. Unfortunately, recurrent PA rupture occurred after drainage and separation of bile and pancreatic juice. Reconsidering our postoperative management, we should have resected the remnant pancreas at this timepoint rather than choose conservative treatment. According to the uneventful postoperative course in the previous report of DP for patients with PBM , we do not believe simultaneous diversion surgery and total pancreatectomy is always necessary. Anastomotic failure after pancreaticoduodenectomy (PD) causes a similar situation of a mixture of pancreatic juice, bile, and intestinal juice. CR-POPF after PD is usually well controlled under optimal drain management. In this case, we placed two drains around the pancreatic stump in the first operation. Additional drain such as Winslow drain might be effective. However, PA rupture from the GDA occurred even after the second operation with additional drains and omental filling. External drainage after DP might not be sufficient for patients with PBM and sphincterotomized papilla. Although prophylactic pancreatic stenting did not reduce CR-POPF and is not usually recommended , ENPD may be effective for patients with PBM and sufficient length of the remnant pancreatic duct.
POPF sometimes causes post-pancreatectomy hemorrhage, which is primarily associated with PA bleeding. In our case, we experienced PA bleeding three times. Recently, endovascular treatment has been recognized as an effective bleeding control technique with a significantly lower mortality rate than relaparotomy . Stent graft placement (SGP) is superior to embolization for bleeding control and helps preserve organ perfusion. However, SGP is challenging when very fragile vessels with unsafe anchoring zones. Selective embolization with metal coils is also an effective and widely used treatment for patients with intact portal flow or collateral arterial flow .
Finally, the patient died of hemorrhagic shock from the portal vein (PV). Bleeding from the PV is a rare morbidity after hepatobiliary and pancreatic surgery . As surgical repair of the PV is technically challenging, endovascular intervention could be considered as an alternative treatment. SGP is preferred over simple embolization to maintain portal blood flow . Although we attempted percutaneous transhepatic approach, we failed to insert a guidewire due to poor intrahepatic portal blood flow.