What is NET?
NET, short for neuroendocrine tumor, is an uncommon cancer that forms in neuroendocrine cells. Neuroendocrine cells carry messages from the nervous system (electrical signals) to the endocrine system, which releases hormones (chemical signals) into the bloodstream that control many body functions, such as the heart rate, digestion and blood pressure. As such, neuroendocrine cells are found in many different organs, including the gastrointestinal (GI) tract, gallbladder, pancreas, thyroid, lungs, pituitary glands, thymus, kidneys, prostate, skin, cervix, ovaries, and testicles. NETs develop when neuroendocrine cells undergo changes that cause them to divide uncontrollably and grow into a mass (referred to as a tumor). While they may simply be called NETs, the location of the tumor is often added to the name (for example, lung NET, bowel NET or pancreatic NET). The place where a NET first forms is called the primary site. Most NETs form within the lungs, digestive tract or the pancreas1.
From its primary site, a NET can spread to other body parts, such as the lymph nodes or the liver. When a tumor spreads to a secondary site, it is called metastasis.
