Pancreas, conglomerate gland lying transversely across the posterior wall of the abdomen. It varies in length from 15 to 20 cm (6 to 8 in) and has a breadth of about 3.8 cm (about 1.5 in) and a thickness of from 1.3 to 2.5 cm (0.5 to 1 in). Its usual weight is about 85 gm (about 3 oz), and its head lies in the concavity of the duodenum.
The pancreas has both an exocrine and an endocrine secretion. The exocrine secretion is made up of a number of enzymes that are discharged into the intestine to aid in digestion. The endocrine secretion, insulin, is important in the metabolism of sugar in the body. Insulin is produced in small groups of especially modified glandular cells in the pancreas; these cell groups are known as the islets of Langerhans. The failure of these cells to secrete sufficient amounts of insulin causes diabetes.
In 1968 a team of surgeons at the medical school of the University of Minnesota performed the first pancreas transplants on four diabetics, using the pancreases of cadavers. Since this first transplant, thousands of pancreas transplants have been performed in the United States. According to the International Pancreas Transplant Registry (IPTR), based at the University of Minnesota, about 14,705 pancreas transplant operations occurred from 1987 to 2003. The majority of these, about 78 percent, were simultaneous pancreas-kidney transplants, known as SPK transplants. These transplants are performed because diabetics also suffer kidney failure. About 14 percent of pancreas transplants are known as pancreas after kidney (PAK) transplants, indicating that a kidney transplant was performed prior to the pancreas transplant. A smaller percentage of transplants, about 6 percent, are pancreas transplants alone (PTA).
Patient survival after one year for transplants performed from 1999 to 2003 was at least 94 percent in all categories and was highest, at 98.4 percent, in the PTA category, according to the IPTR. The ten-year survival rate, based on data from 1987 to 1992, was 68 percent for PTA transplants, 63 percent for SPK transplants, and 54 percent for PAK transplants. Patients who have pancreas transplants must take immunosuppressant drugs, such as cyclosporine, for the remainder of their lives. See also Medical Transplantation.
Diseases of the pancreas are relatively rare. Cancer of the pancreas is rare but deadly. It is the fourth leading cause of cancer death in the United States and the fifth leading cause worldwide. The mortality rate is high because pancreatic cancer produces few if any symptoms and so is often not detected until it has spread to other organs. Smoking is thought to cause about 30 percent of pancreatic cancers. Hemorrhage in the pancreas and acute pancreatitis are also serious conditions. If not treated quickly, they may cause death. The symptoms are not definite, resembling those of peritonitis or intestinal obstruction.