About neuroendocrine tumors

A neuroendocrine cancer, often referred as a neuroendocrine tumor (NET) or neuroendocrine neoplasm, begins in the specialized cells of the body’s neuroendocrine system. These cells have traits of both hormone-producing endocrine cells and nerve cells. They are found throughout the body’s organs and help control many of the body’s functions. Hormones are chemical substances that are carried through the bloodstream to have a specific effect on the activity of other organs or cells in the body. Most NETs take years to develop and grow slowly. However, some NETs can be fast-growing. Grades

NETs can begin in any part of the body, including:

• Gastrointestinal (GI) tract. NETs develop most commonly in the GI tract, specifically in the large intestine (20%), small intestine (19%), and appendix (4%). The GI tract plays a central role in digesting foods and liquid and in processing waste. GI tract NETs used to be called carcinoid tumors.

• Lung. The lung is the second most common location of NETs. About 30% of NETs occur in the bronchial system, which carries air to the lungs. Lung NETs also used to be called carcinoid tumors.

• Pancreas. Approximately 7% of NETs can develop in the pancreas, a pear-shaped gland located in the abdomen between the stomach and the spine. Pancreas NETs used to be called islet cell tumors.

NETs can also begin in other organs. In about 15% of cases, a primary site cannot be found. Sometimes, NETs may develop in or on the adrenal glands. These rare types of NETs are called pheochromocytoma and paraganglioma.