[Villous tumors of the Wirsung's duct and pancreatic intraductal adenocarcinoma: interrelation or accidental association?].

Villous neoplasms of the main pancreatic duct are uncommon. Two cases of neoplasm of the main cephalic pancreatic duct in 61- and 42-year-old patients presenting with long standing (10 and 12 years) history of abdominal pain are reported. In both cases, duodenal fistula was present and mucus was observed by endoscopy at the fistula and major papilla levels. Endoscopic retrograde pancreatography showed a stricture of the main pancreatic duct in the pancreatic head. In one case, with incomplete stricture, pancreatic ducts disclosed typical features of chronic obstructive pancreatitis and contained mucus casts. Histologic examination of total and proximal duodenopancreatectomy showed a villous neoplastic pattern with focal malignant changes within the main pancreatic duct. The adjacent pancreatic tissue showed signs of stromal invasion without lymph node or nervous infiltration. Glandular parenchyma was atrophic in the pancreatic body and tail, with extensive fibrosis, and the pancreatic duct depicted signs of nonpapillary hyperplasia. Histochemical study disclosed a predominant sialomucin secretion by villous adenoma and sulfomucin secretion by epithelial cells lining the accessory or main caudal pancreatic ducts. These results lead us to suggest a possible relationship between villous adenoma of ducts and pancreatic adenocarcinoma.