A Case of Acinar Cell Carcinoma with Broad Intraductal Extension

mono-clonal anti-BCL10 antibody（clone 331.1）is a sensitive and specific marker of pancreatic acinar cell carcinoma and pancreatic metaplasia. Virchows Arch 454 : 133-142, 2009 A 56-year-old woman with epigastralgia and elevation of the hepatobiliary enzyme levels was referred to our hospital. Abdominal contrast-enhanced computed tomography and magnetic resonance imaging showed a tumor in the pancreatic head with broad extension into the main pancreatic duct. Fur-thermore, the tumor extension into the pancreatic duct reached up to the tail of the pancreas. Upper gastrointestinal endoscopy revealed a tumor protruding from the duodenal papilla, and an endoscopic biopsy suggested the diagnosis of tubular adenocarcinoma. Surgery was performed based on the suspected diagnosis of tubular adenocarcinoma arising primarily from the main pancreatic duct. Total pancreatectomy and splenectomy with lymph node dis-section were performed. Histopathologically, the resected specimens revealed broad intraductal growth and extraductal invasion over a small area. It was difficult to determine whether the tumor was an intraductal tubulopapillary neoplasm or an acinar cell carcinoma on the basis of the routine microscopic findings. However, immunohistochemistry confirmed the diagnosis of acinar cell carcinoma. The patient was discharged without serious complications, and no evidence of recurrence has been seen until now, 18 months since the surgery. We report this case of acinar cell carcinoma that primarily arose from the pancreatic duct, with a review of the literature.