Groove pancreatitis masquerading as pancreatic carcinoma.

The clinicopathologic and radiologic features of groove pancreatitis masquerading as pancreatic carcinoma in eight Japanese patients were reviewed. All patients were men with a mean age of 58 years. Three patients complained of abdominal pain whereas others had jaundice. The jaundice fluctuated in one patient. Four patients had several episodes of pancreatitis, and four patients were alcoholics. Radiologically, a duodenal stricture was evident in five patients, biliary stenosis in six, pancreatic duct stenosis in four, and a mass in the pancreatic head in six. The biliary stenosis was characterized by smooth tapering, which improved after biliary drainage in three cases. Of the four patients who underwent angiography, two showed an encasement of vessels, one a hypervascular mass, and the other no abnormality. All patients underwent a pancreatoduodenectomy for suspected pancreatic carcinoma. However, the histopathologic diagnosis was chronic pancreatitis confined to the groove between the distal common bile duct, duodenum, and pancreas. The duodenum showed scarring and hyperplasia of the Brunner's gland. The biliary stenosis was produced by fibrosis and chronic inflammation around the distal common bile duct. Groove pancreatitis presents various clinical features, such as biliary obstruction, duodenal stenosis, and pancreatic mass, and often masquerades as pancreatic head carcinoma. This condition should be kept in mind when making a diagnosis of pancreatic head carcinoma to avoid an unnecessary radical operation.