The endocrine system includes specialized glands that make and release hormones — or chemical messengers — directly into the bloodstream. Hormones regulate a wide range of body functions, such as activities of entire organs; growth and development; reproduction; sexual characteristics; usage and storage of energy; and levels of fluid, salt, and sugar in the blood.
A neuroendocrine tumor is an abnormal growth that arises from the glands that produce these hormones. The tumor itself can also produce hormones on its own in high amounts and cause serious illness. Some neuroendocrine tumors impair quality of life by triggering uncomfortable symptoms, while others have the potential to be life-threatening.
Neuroendocrine tumors develop in many digestive organs, including the pancreas, liver, stomach, small intestine, appendix, large intestine, and rectum, as well as other areas in the abdomen. Physicians in the Neuroendocrine Program at NewYork-Presbyterian/Weill Cornell Medical Center are highly skilled in the diagnosis and treatment of neuroendocrine tumors. They use the latest diagnostic tests and treatments to treat these tumors and restore quality of life to patients. When diagnosed and treated appropriately, the prognosis for most patients with neuroendocrine tumors is very good.
There are different types of neuroendocrine tumors. Some produce hormones, while others do not. Neuroendocrine tumors that grow without producing hormones are called "non-functioning tumors." Tumors that secrete hormones into the bloodstream are called "functional tumors."
Pancreatic Neuroendocrine Cancers
Pancreatic neuroendocrine cancers are uncommon and arise in the insulin-producing cells of the pancreas called islet cells. These tumors account for just five percent of pancreatic tumors and tend to be treatable, slow-growing tumors. (Most tumors found in the pancreas arise from ducts and are called adenocarcinomas — what is commonly known as pancreatic cancer — and are more challenging to treat.)
Functional pancreatic neuroendocrine tumors secrete hormones directly into the bloodstream and lead to dramatic hormone-related symptoms and metabolic imbalances. They tend be very small — only a few millimeters in size — when the patient experiences significant symptoms, and for this reason they often remain only in the pancreas.
Most pancreatic islet cell tumors are non-functioning. Because they do not release any hormones into the blood that can cause symptoms, they grow silently for a long time before they are discovered, and are typically diagnosed at more advanced stages of disease — when the tumor becomes big enough to push against other structures. They may cause obstructive symptoms of the biliary tract or duodenum, bleeding into the gastrointestinal tract, or abdominal masses. Patients may also experience nausea, vomiting, abdominal pain, back pain, and jaundice (yellowing of the skin).
More than half of these non-functioning tumors are malignant (cancerous) at the time of diagnosis. They may account for as many as 60 percent of all neuroendocrine tumors of the pancreas.