For an explanation of the pancreas, please see the description under "What is the pancreas?" in Pancreatic Diseases.
What is pancreatic cancer?
Cancer is an uncontrolled growth of abnormal cells that form tumors, damage normal tissue, and that may eventually spread (metastasize). Most pancreatic cancers (about 95%) develop in the pancreatic ducts and sometimes develop in the enzyme-producing cells of the exocrine pancreas.
Endocrine pancreatic tumors, also known as islet cell tumors, are usually less aggressive than exocrine tumors and are more rare. The majority of them are benign tumors that do not metastasize, although some are malignant. Islet cell tumors include gastrinomas, glucagonomas, and insulinomas and occur in the pancreatic cells that make the hormones gastrin, glucagon, and insulin, respectively. They often are detected earlier than exocrine cancers because they cause the signs and symptoms of excessive amounts of insulin and glucagon. Simple blood tests for these hormones are used to measure hormone levels in the blood and confirm if the levels are in fact elevated.
Because they are more common and aggressive, the remainder of this discussion focuses on exocrine cancers. Unfortunately, these cancers are hard to detect at an early stage. Since the pancreas is deep in the body, developing tumors cannot usually be seen or felt during a physical examination. By the time symptoms develop, the cancer has often spread throughout the pancreas and beyond.
According to the American Cancer Society, rates of pancreatic cancer have been slowly increasing over the past 10 years. In 2014, a projected 46,420 Americans will be diagnosed with pancreatic cancer and an estimated 39,590 will die from it. Pancreatic cancer is the fourth leading cause of cancer death in the United States, primarily because only about 10% of the cancers are still contained within the pancreas at the time of diagnosis.