The pancreas can also be thought of as having different functional components, the endocrine and exocrine parts. Tumors can arise in either part. However, the vast majority arise in the exocrine (also called non-endocrine) part. Since the parts have different normal functions, when tumors interfere with these functions, different kinds of symptoms will occur.
|Islets of Langerhans||These are the endocrine (endo= within) cells of the pancreas that produce and secrete hormones into the bloodstream. The pancreatic hormones, insulin and glucagon, work together to maintain the proper level of sugar in the blood. The sugar, glucose, is used by the body for energy.|
|Acinar cells||These are the exocrine (exo= outward) cells of the pancreas that produce and transport chemicals that will exit the body through the digestive system. The chemicals that the exocrine cells produce are called enzymes. They are secreted in the duodenum where they assist in the digestion of food.|
The pancreas is an integral part of the digestive system. The flow of the digestive system is often altered during the surgical treatment of pancreatic cancer. Therefore it is helpful to review the normal flow of food before reading about surgical treatment.
Food is carried from the mouth to the stomach by the esophagus. This tube descends from the mouth and through an opening in the diaphragm. (The diaphragm is a dome shaped muscle that separates the lungs and heart from the abdomen and assists in breathing.)
Immediately after passing through the diaphragm's opening, the esophagus empties into the stomach where acids that break down the food are produced. From the stomach, the food flows directly into the first part of the small intestine, called the duodenum. It is here in the duodenum that bile and pancreatic fluids enter the digestive system.
Bile is a greenish-yellow fluid that aids in the digestion of fats. After being produced by cells in the liver, the bile travels down through the bile ducts which merge with the cystic duct to form the common bile duct. The cystic duct runs to the gallbladder, a small pouch nestled underneath the liver. The gallbladder stores extra bile until needed. The common bile duct actually enters the head of the pancreas and joins the pancreatic duct to form the ampulla of Vater which then empties into the duodenum. Flow of bile indicated by green arrows.
Instead of carrying bile, the pancreatic duct carries the pancreatic fluid produced by the acinar cells (exocrine) of the pancreas. The pancreatic duct runs the length of the pancreas and joins the common bile duct in the head of the pancreas. These ducts join to form the ampulla of Vater which then empties into the duodenum. Flow of pancreatic fluid indicated by dark yellow arrow.
The food, bile and pancreatic fluid travels through many more feet of continuous intestine including the rest of the duodenum, jejunum and ileum which comprise the small intestine, then through the cecum, large intestine, rectum, and anal canal.