Pancreatic diseases associated with pancreas divisum.

AIM To clarify the features of acute or chronic pancreatitis and pancreatic tumors associated with complete and incomplete pancreas divisum. METHODS Clinical features of pancreatic diseases associated with complete (n = 54) and incomplete (n = 50) pancreas divisum were examined. RESULTS Acute and chronic pancreatitis occurred more frequently in patients with complete pancreas divisum (22.2%: 12/54, and 18.5%: 10/54, respectively) than in controls (5.6%: 183/3,246, and 4.9%: 159/3,246, respectively; p < 0.01). In 8 patients with chronic pancreatitis, the dorsal pancreatic duct was irregularly dilated from the orifice to the tail, whereas the ventral pancreatic duct was not dilated (isolated dorsal pancreatitis). None of the 12 complete pancreas divisum patients with acute pancreatitis consumed heavy or moderate amounts of alcohol. Although 6 of 10 patients with chronic pancreatitis consumed heavy or moderate amounts of alcohol, 31 of 32 patients with this malformation who did not exhibit pancreatitis consumed little or no alcohol. Chronic pancreatitis occurred more frequently in patients with incomplete pancreas divisum (18.0%: 9/50) than in controls (4.9%: 159/3,246; p < 0.01). Of 54 patients with complete pancreas divisum, 6 patients (11.1%) were associated with pancreatic tumor. All tumors developed from the dorsal pancreas of pancreas divisum. CONCLUSIONS Complete pancreas divisum can be the sole etiology of acute or chronic pancreatitis. The presence of another factor, such as alcohol abuse, may be required for chronic pancreatitis to develop in some patients with complete or incomplete pancreas divisum. In complete pancreas divisum, the dorsal pancreatic duct might be a factor that promotes oncogenesis.