Dorsal pancreatic duct dominance in pancreaticobiliary maljunction.

OBJECTIVES

In patients with pancreaticobiliary maljunction (PBM), reflux of pancreatic juice to the bile duct may contribute to carcinogenesis of the biliary tract. This study aimed to investigate the pancreatographic findings in patients with PBM and the relationship to their clinical findings in view of pancreatic juice flow.

METHODS

Seventy-eight cholangiopancreatograms were reviewed. When the maximum diameter of the Santorini duct was almost equal to or greater than that of the ventral pancreatic duct, the relationship between the 2 ducts was defined as dorsal pancreatic duct (DPD) dominance.

RESULTS

Pancreatographic findings were divided into 2 groups: a normal duct group (69 patients) and a DPD dominant group (9 patients). Although 40 patients (58%) with biliary carcinoma were identified in the normal duct group of PBM, only 1 gallbladder carcinoma (11%) occurred in DPD-dominant patients (P < 0.01). A large-caliber Santorini duct was noted to flow straight from the upstream DPD in all patients with DPD dominance. Concentration of amylase in the bile of DPD dominance was significantly lower than that of normal pancreatic duct system (P < 0.01).

CONCLUSIONS

In PMB with DPD dominance, most pancreatic juice in the upper DPD is drained into the duodenum through the minor duodenal papilla, and reflux of pancreatic juice to the biliary tract might be reduced, resulting in reduced frequency of associated biliary carcinogenesis.