Chronic obstructive pancreatitis due to tiny (0.6 to 8 mm) benign tumors obstructing pancreatic ducts: report of three cases.

Three cases of obstructive pancreatitis are described in nonalcoholic women aged 56 to 58 years with a 2-month to 5-year history of recurrent attacks of pancreatic pain associated with intermittent raised serum pancreatic enzymes. The diagnosis was made by sonography showing an enlarged hyperechogenic tail of the pancreas, with a dilated duct, the rest of the pancreas being normal, and by ERCP showing a partial stenosis of the main pancreatic duct with regular dilatation of collateral branches distally to it. Surgical resection of the pancreatic tail cured all three patients. In the obstructed part of the pancreas, the lesions are typical of obstructive pancreatitis with perilobular and sometimes intralobular fibrosis of the same degree in the different lobules of the diseased area and not patchy as in chronic calcifying pancreatitis. The changes in collateral ducts are not marked, and there is an absence of intraductal plugs. Fat necrosis and pseudocysts may be found. Tumors responsible for the obstruction were the smallest islet cell tumors (0.6 and 8 mm) and serous cystadenoma (5 mm) responsible for symptoms ever published. Cephalad to the stricture, the pancreas was normal. When the etiology of chronic pancreatitis is atypical, especially when it occurs in nonalcoholic women aged greater than 50 years, a careful sonography (or computed tomographic scan) and ERCP must be done. Serial sections of the resected pancreas at the level of the obstruction and distal to it are often necessary to demonstrate the tumor.