What is the pancreas?
The pancreas is an organ approximately six inches long that is located in the abdomen behind the stomach and in front of the spine and aorta. The pancreas is divided into three regions; the head, the body, and the tail. The head of the pancreas is located on the right side of the abdomen adjacent to the duodenum. The tail is on the left side of the abdomen, and the body lies between the head and the tail.
There are two parts to the pancreas, referred to as the exocrine and endocrine parts. The majority of the cells of the pancreas produce digestive juices which contain the enzymes necessary for digesting food in the intestine. The enzymes are secreted into smaller collecting ducts within the pancreas (side branches). The side branches empty into a larger duct, the main pancreatic duct, which empties into the intestine through the papilla of Vater in the duodenum. During passage through the ducts, bicarbonate is added to the digestive enzymes to make the pancreatic secretion alkaline. The cells and ducts producing the digestive juices comprise the exocrine part of the pancreas.
Just before the main pancreatic duct enters the duodenum, it usually merges with the common bile duct that collects bile (a fluid that helps to digest fat) produced by the liver. The common bile duct usually joins the pancreatic duct in the head of the pancreas. The union of these two ducts forms the ampulla of Vater which drains both the bile and pancreatic fluid into the duodenum through the papilla of Vater.
Buried within the tissue of the pancreas are small collections of cells, termed the Islets of Langerhans. The cells of the Islets produce several hormones, for example, insulin, glucagon, and somatostatin; that are released into the blood (the islets do not connect with the pancreatic ducts) and travel in the blood to other parts of the body. These hormones have effects throughout the body, for example, insulin, which helps to regulate blood sugar levels. The hormone-secreting portion of the pancreas - the Islets - is the endocrine part of the pancreas.
What are pancreatic cysts?
Pancreatic cysts are collections (pools) of fluid that can form within the head, body, and tail of the pancreas. Some pancreatic cysts are true cysts (non-inflammatory cysts), that is, they are lined by a special layer of cells that are responsible for secreting fluid into the cysts. Other cysts are pseudocysts (inflammatory cysts) and do not contain specialized lining cells. Often these pseudocysts contain pancreatic digestive juices because they are connected to the pancreatic ducts. Pancreatic cysts can range in size from several millimeters to several centimeters. Many pancreatic cysts are small and benign and produce no symptoms, but some cysts become large and cause symptoms, and others are cancerous or precancerous. (Precancerous cysts are benign cysts that have the potential to become cancerous.)
Different types of cysts contain different types of fluids. For example, pseudocysts that form after an attack of acute pancreatitis contain digestive enzymes such as amylase in high concentrations. Mucinous cysts contain mucus (a proteinaceous liquid) produced by the mucinous cells that form the inside lining of the cyst.