A case report of papilla Vater carcinoma showing positive expression of thymidine phosphorylase.

Recently, we experienced an interesting case of papilla Vater carcinoma. The patient was a 61-year-old woman, who was referred to our department from a private hospital with a chief complaint of high fever. Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography revealed an anomalous arrangement of the pancreaticobiliary duct without a common channel and a tumor, which was detected on the papilla Vater and diagnosed as well-differentiated adenocarcinoma. Pylorus-preserving pancreaticoduodenectomy with lymph node dissection was performed. The immunohistochemical stain showed the strong expression of thymidine phosphorylase in the tumor tissue and also in the normal biliary tract, despite positive p53 cells being undetected in either tumor tissue or epithelium of biliary tract. These findings may suggest important indications to consider some mechanisms of carcinogenesis in the biliary tract.