Pancreatic tumors ductal adenocarcinoma

Mesothelin is a 40-kD glycoprotein of unknown function that is strongly expressed in mesothelial cells, ovarian serous cells, and pancreatic-bile duct cells. Using monoclonal antibody 5B2, Ordonez found it to immu-nostain normal mesothelial cells, mesotheliomas, non-mucinous ovarian carcinomas, and occasionally other neoplasms. Ordonez concluded that mesothelin staining could be used to diagnose mesotheliomas, although it was expressed in 14 of 14 ovarian carcinomas, 12 of 14 pancreatic ductal adenocarcinomas, 7 of 12 desmoplastic small round cell tumors, and 9 of 9 synovial sarcomas. Therefore, this antibody should be interpreted carefully. 

Abraham SC, Klimstra DS, Wilentz RE, et al. Solid-pseudo-papillary tumors of the pancreas are genetically distinct from pancreatic ductal adenocarcinomas and almost always harbor beta-catenin mutations. Am J Pathol. 2002 160 1361-1369. 

In the pediatric population, pancreatic tumors are very unusual entities. They account for less than 5% of all malignancies in children. These tumors may arise from the exocrine or endocrine pancreas. Exocrine neoplasias include ductal adenocarcinoma, acinar adenocarcinoma, pancreaticoblastoma, or infantile adenocarcinoma. Endocrine tumors or islet cell tumors are named after the hormone produced, with insulinoma being the most common in children (Walker 1996). 

The pancreatic phase of contrast enhancement optimizes our ability to detect pancreatic adenocarcinoma and differentiate it from normal pancreatic tissue. Studies have shown that because pancreatic ductal adenocarcinoma often has a marked desmoplastic response associated with it, it will be hypo-attenuating relative to the normal pancreas after contrast enhancement during the pancreatic phase (Lu et al. 1997). The degree of tumor conspi-cuity is enhanced during the pancreatic phase and decreases during the portal venous phase. This... 

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