About Neuroendocrine Tumors

What is a neuroendocrine tumor? Most people know very little about neuroendocrine tumors, until they are diagnosed. It is a frightening and stressful experience to learn you have a neuroendocrine tumor (NET).   This site offers information and resources to help patients and caregivers face a neuroendocrine tumor diagnosis.

The Neuroendocrine Tumor Research Foundation focuses solely on neuroendocrine tumors. We fund research in search of a cure and we offer educational resources to patients, caregivers, and families living with neuroendocrine tumors.  No matter where you are in your journey, we can help you:

What is a neuroendocrine tumor?

A neuroendocrine tumor (NET) is an uncommon cancer type that forms in neuroendocrine cells (Neuroendocrine tumors may also be called islet cell tumors, carcinoid cancer, or carcinoid tumors). NETs can occur almost anywhere in the body, but neuroendocrine tumors most commonly form in the gastrointestinal tract, lung, and pancreas. Neuroendocrine tumors form in neuroendocrine cell

Neuroendocrine cells can be found in many different organs. They carry messages from the nervous system to the endocrine system. In response to these messages, the endocrine system makes and releases hormones that control body functions like blood pressure, heart rate, digestion, breathing, and blood sugar. Neuroendocrine cells occur in these organs:

  • Gastroinstenial tract (small intestine, rectum, stomach, colon, esophagus, appendix)
  • Gallbladder
  • Pancreas (islet cells)
  • Thyroid
  • Lungs
  • Pituitary glands
  • Thymus
  • Kidneys
  • Liver
  • Prostate
  • Skin
  • Cervix
  • Ovaries
  • Testicles

What do neuroendocrine tumors do?

Some neuroendocrine tumors make and release hormones, which can cause a lot of disruptive symptoms. When a NET produces hormones, it is called a “functional” neuroendocrine tumor. When a NET does not produce hormones, it is called a “nonfunctional” neuroendocrine tumor.

Functional neuroendocrine tumors produce “peptide” hormones. Peptide is a type of hormone that is made up of amino acids. Some of the peptide hormones NETs produce include:

  • Somatostatin receptors
  • Vasoactive intestinal peptide (VIP)
  • 5-hydroxytryptamine serotonin (5-HT)
  • Gastrin
  • Glucagon

The excess peptide hormones released by a neuroendocrine tumor can cause signs and symptoms.

What are the signs and symptoms of neuroendocrine tumors?

Signs and symptoms of neuroendocrine tumor vary depending on where the tumor is located. Learn about neuroendocrine tumor sites:

What causes neuroendocrine tumors?

Sometimes, something goes wrong inside the neuroendocrine cell and it stops behaving as it should. The neuroendocrine cell grows and divides faster than it should. The excess cells form tumors. We don’t yet know at what point in the neuroendocrine cell lifecycle it becomes cancer. But the Neuroendocrine Tumor Research Foundation has funded millions of dollars in scientific research to answer this question. See what we are learning. 

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171 K
Americans live with NETs
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The median length of time that passes from first symptom to diagnosis2
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Of patients had metastases at diagnosis2

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1Dasari A, Shen C, Halperin D, et al. Trends in the incidence, prevalence, and survival outcomes in patients with neuroendocrine tumors in the United States. JAMA Oncol. 2017;3(10):1335-1342.

2Singh S, Granberg D, Wolin E, et al. Patient-reported burden of a neuroendocrine tumor (NET) diagnosis: results from the first global survey of patients with NETs. J Glob Oncol. 2016;2(1):43-53.