What is the pancreas?

The pancreas is a large gland situated deep in the abdomen (tummy) in between the stomach and the spine. It is about 15cm (6 inches) long and shaped a bit like a tadpole. The widest part is called the head, which lies close to the small intestine (duodenum) on the right side of the abdomen. The middle part is called the body and the thin part is the tail, which extends towards the left side of the body, next to the spleen.

The pancreas is surrounded by a number of other large and important organs and blood vessels:

• the liver, stomach, spleen, intestines and gall bladder are all close to the pancreas

• the head of the pancreas is closely attached to the duodenum (the top part of the small intestines)

• the pancreatic duct empties into the duodenum

• the common bile duct, which carries bile from the liver, passes through the head of the pancreas to empty in the duodenum

• the superior mesenteric artery and vein are close to the pancreas

• the blood supply to the liver, intestines, kidneys and lower part of the body can all be in contact with the pancreas.

The pancreas is both an exocrine gland (produces enzymes) and an endocrine gland (produces hormones). It has two main functions.

• It makes pancreatic juices containing enzymes that help to break down food so that the body can absorb it. This digestive juice flows through a series of ducts (tubes) into the main pancreatic duct which runs the length of the pancreas. This duct transports the digestive juice into the duodenum. The exocrine cells that produce and transport enzymes are called acinar cells.

• The pancreas also produces a number of hormones that enter the body and flow around the bloodstream. The most important of these is insulin, which helps to regulate the amount of sugar in the blood. The endocrine cells that produce and secrete hormones are found mainly in the islets of Langerhans.

Both these functions can be affected if the pancreas isn't working properly.

Pancreatic cancer can occur in both exocrine and endocrine cells. Depending on exactly where they begin to grow cancers behave differently and cause different symptoms. You can find out more about pancreatic cancer here.