Pancreatic neuroendocrine tumors (pancreatic NETs or PNETs) account for about 7 percent of all pancreatic tumors. They may be benign or malignant and they tend to grow slower than exocrine tumors. They develop from the abnormal growth of endocrine (hormone-producing) cells in the pancreas called islet cells. This is why these tumors are sometimes referred to as “islet cell tumors.”
Some of the hormones islet cells produce include insulin, glucagon and somatostatin. Insulin and glucagon are the two main pancreatic hormones. Insulin lowers blood sugar levels, while glucagon raises blood sugar levels. Together, these two main hormones work to maintain the proper level of sugar in the blood. Somatostatin regulates the levels of a variety of other hormones in the blood.