Ampullary (AM-poo-la-ree) cancer is a rare cancer that forms in an area of your digestive system called the ampulla of Vater. The ampulla of Vater is located where your bile duct and pancreatic duct join and empty into your small intestine.
https://www.mayoclinic.org/diseases-conditions/ampullary-cancer/symptoms-causes/syc-20355066