This case shows a lesion of the ampulla of Vater however the double duct sign is not displayed. This sign, seen in the majority of tumors of the ampulla of Vater, consists of a dilated pancreatic duct and common bile duct at the same time.  A normal-sized pancreatic duct does not however exclude the diagnosis of ampullary neoplasm because the ductal caliber will be normal in up to 50% in patients with bile duct obstruction caused by an ampullary tumor.