Pancreaticobiliary maljunction without biliary dilatation in pediatric patients.

PURPOSE: Pancreaticobiliary maljunction (PBM) without biliary dilatation is a condition in which dilatation of the bile duct is not seen in patients with PBM. Recently, the Japanese Study Group on Pancreaticobiliary Maljunction (JSGPM) published new diagnostic criteria for PBM. In these criteria, biliary dilatation is defined according to the standard diameter at each age. We reviewed cases of pediatric patients with PBM without biliary dilatation. METHODS: From 1992 to 2019, 134 patients with PBM were treated in our institution. Among these, 7 patients were retrospectively diagnosed with PBM without biliary dilatation. The clinical information was retrospectively assessed in these patients. RESULTS: Of the seven patients, six were female. All patients had symptoms similar to those of patients with congenital biliary dilatation. In all seven patients, the diagnosis of PBM was made before definitive surgery. Six patients had type B PBM, and one had type D PBM. All patients underwent extrahepatic bile duct resection and hepaticojejunostomy, and their symptoms resolved. One patient experienced postoperative complications of anastomotic leakage followed by anastomotic stricture. CONCLUSION: The present report revealed important clinical features of this entity. However, there are still some issues that need to be discussed, and further research is needed.

Mechanism of pancreatic juice reflux in pancreaticobiliary maljunction: A fluid dynamics model experiment.

BACKGROUND: Pancreatic juice reflux to the common bile duct and gallbladder is observed in the pancreaticobiliary maljunction (PBM), and various pathological conditions occur in the biliary tract. However, the mechanism of pancreatic juice reflux has not been discussed yet. This study aimed to investigate the mechanism of this phenomenon from the perspective of the fluid dynamics theory. METHODS: A fluid dynamics model of PBM without biliary dilatation having gallbladder function and of the pressure of sphincter of Oddi was developed. Water (as bile juice and pancreatic juice) was flowed to these models with a flow rate similar to that in humans. Pancreatic and bile juice flow and bile duct pressure were observed in three phases of gallbladder function. Moreover, the same experiment was performed in the PBM without biliary dilatation model without gallbladder. RESULTS: Pancreatic juice reflux could be observed when the gallbladder was passively expanded with the pressure in the bile duct lower than that in the sphincter of Oddi. However, pancreatic juice reflux was not observed in the model without gallbladder. CONCLUSIONS: Gallbladder function may be strongly involved in pancreatic juice reflux in PBM without biliary dilatation. Cholecystectomy may be able to stop the reflux of pancreatic juice.

Classification of pancreaticobiliary maljunction and its clinical features in adults.

BACKGROUND: In pancreaticobiliary maljunction (PBM), reflux of pancreatic juice and bile produces various pathological conditions in the biliary tract and pancreas. Clinical features according to the classification of PBM by confluence between the distal bile duct and the main pancreatic duct proposed in 2015 were evaluated in children. METHODS: Clinical features and complicating diseases according to the PBM classification were evaluated in 168 adult PBM patients. Patency of Santorini duct and associated biliary carcinomas were evaluated in 123 patients. RESULTS: Similar to children, there were significant differences in age (P < 0.01) and type of common bile duct (P < 0.01) between the groups of the classification. Unlike in children, there was no significant difference in the incidence of abdominal pain and hyperamylasemia. There were 87 associated biliary carcinomas (79 gallbladder carcinomas and eight cholangiocarcinomas). PBM patients with a cudgel-type Santorini duct, which is greater than 2 mm in diameter, did not develop biliary carcinomas, compared to 61.1% of those with other types of Santorini duct (P < 0.01). CONCLUSIONS: Clinical features according to the PBM classification in adults were different from those in children. Although biliary carcinomas were frequently seen in adult PBM patients, none of those with a cudgel-type Santorini duct developed biliary carcinoma.

A Large Carcinosarcoma of the Gallbladder Accompanied by Pancreaticobiliary Maljunction: A Case with a Six-year Survival.

Pancreatobiliary maljunction (PBM) is a rare congenital malformation, often associated with adenocarcinoma. However, PBM accompanying gallbladder carcinosarcoma has rarely been reported. A 72-year-old woman was referred to our hospital, complaining of abdominal pain. Computed tomography showed a polypoid mass in the gallbladder. Endoscopic retrograde cholangiopancreatography showed PBM, and aspirated bile demonstrated elevated levels of pancreatic-type amylase (26,780 U/L) and cancer cells. Extended cholecystectomy was performed. Histologically, the tumor had adenocarcinoma, squamous cell carcinoma and sarcoma components. Despite the large tumor size (84 mm) and intra-vessel cancer permeations, this patient has been healthy for 73 months since the surgery.