Poorly Differentiated Adenocarcinoma with Signet-ring Cell Carcinoma of the Extrahepatic Bile Duct in a 42-year-old Japanese Female: A Case Report

Poorly differentiated adenocarcinoma without papilla or tubule formation of the extrahepatic bile duct is rare. Here we present a case (a 42-year-old Japanese woman) without either pancreatobiliary maljunction or liver disease. The patient had obstructive jaundice. Imaging studies revealed a bile duct tumor obstructing the common bile duct and invading the surrounding tissues. Pathologic examination revealed a dense periductal growth of poorly differentiated adenocarcinoma containing signet-ring cells, but without papilla or tubule formation in the extrahepatic bile duct. The tumor cells directly invaded the pancreatic parenchyma and the portal vein. In the extrahepatic bile duct, poorly differentiated adenocarcinoma may be established as a distinct clinicopathologic entity if the tumors are characterized by:1) the absence of papilla or tubule formation, 2) Asian preponderance, 3) occurrence at a younger age than is usual for patients with biliary cancers, and 4) an aggressive mural invasiveness.</p

Membranous and cytoplasmic expression of epidermal growth factor receptor in metastatic pancreatic ductal adenocarcinoma

PublisherRecent studies indicate the clinical significance of the cellular localization of epidermal growth factor receptor (EGFR) in a variety of cancer types. Internalization of activated EGFR is reported to be closely associated with patient prognosis. This study investigated the clinical significance of the immunohistochemical localization of EGFR in patients with metastatic pancreatic cancers compared to those with surgically resected pancreatic cancers. Using 44 surgically resected primary pancreatic cancers and 40 primary or meta-static tumors from 20 autopsied patients with far advanced pancreatic cancers, the incidence of membranous and cytoplasmic EGFR overexpression was compared between primary tumors and far advanced tumors by immunohistochemistry using the Dako EGFR pharmDx™ kit, a global standard kit for EGFR assay. In the 44 surgically resected cancers, 13 (30%) exhibited membranous overexpression of EGFR, comprising 1 case (2%) with score 3+ and 12 cases (27%) with score 2+ and 10 (23%) exhibited cytoplasmic overexpression of EGFR. In the 40 tumors at a far advanced stage, the percentage of samples exhibiting positivity for membranous and cytoplasmic EGFR overexpression was 48% (19 of 40) comprising 7 (18%) with score 2+ and 12 (30%) with score 3+ and 33% (13 of 40), respectively. The far advanced tumors tended to show membranous and cytoplasmic EGFR overexpression more frequently than the surgically resected tumors, although the difference was not significant. These findings suggest that membranous and cytoplasmic overexpression of EGFR may be indicative of the potential aggressiveness of pancreatic cancers