Rare Oncology News

Disease Profile

Neuroendocrine tumor

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Neuroendocrine neoplasia; Neuroendocrine neoplasm


A neuroendocrine tumor (NET) is a rare type of tumor that arises from specialized body cells called neuroendocrine cells. These cells have traits of both nerve cells and hormone-producing cells, and release hormones into the blood in response to signals from the nervous system.[1][2] Because a neuroendocrine tumor arises from cells that produce hormones, the tumor can also produce hormones.[2]

Neuroendocrine tumors can develop anywhere in the body, but most occur in the digestive tract, pancreas, rectum, lungs, or appendix.[1][2][3] They can be non-cancerous (benign) or cancerous (malignant).[1] They usually grow slowly over many years, but there are fast-growing forms.[2][4]

There are many types of neuroendocrine tumors, but most are classified as one of two main types:[2][3]

  • Carcinoid tumors NETs that most commonly arise in the digestive tract, lungs, appendix or thymus. They can also grow in the lymph nodes, brain, bone, gonads (ovaries and testes) or skin.[2][5]
  • Pancreatic neuroendocrine tumors (also called islet cell tumors) NETs that typically arise in the pancreas, although they can occur outside the pancreas.[6]

A pheochromocytoma is another, rarer type of NET that usually develops in the adrenal gland, but can also arise in other parts of the body.[2]

Signs and symptoms depend on the tumor's type, size and location; whether it produces hormones; and whether it has spread to other parts of the body (metastasized).[2] NETs are typically described as functional or nonfunctional. Functional NETs produce a specific set of symptoms due to the production of excess hormones, while non-functional NETs generally do not cause specific symptoms. In many cases, a person has no symptoms until the tumor spreads to the liver and/or impairs the function of an organ or system. This can make NETs very hard to diagnose.[7]

The majority of NETs are not inherited and occur sporadically in people with no family history of NETs.[3] However, some NETs are associated with a hereditary cancer or tumor syndrome such as multiple endocrine neoplasia type 1 (most commonly), Von Hippel-Lindau disease, tuberous sclerosis, or neurofibromatosis type 1 (NF1). Inheritance of each of these is autosomal dominant.[3]

Treatment of NETs depends on many factors such as the tumor's type, location, aggressiveness, and hormone-producing capabilities; as well as whether it has metastasized.[1] Management options may include surveillance, surgery to remove the tumor and/or surrounding tissue, and various non-surgical therapies to shrink the tumor, stop it from growing, or manage symptoms.[8][9][10]


Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.


    The resources below provide information about treatment options for this condition. If you have questions about which treatment is right for you, talk to your healthcare professional.

    Management Guidelines

    • The North American Neuroendocrine Tumor Society has published several consensus guidelines relating to the medical treatment and management of neuroendocrine tumors. Guidelines are developed pursuant to National Institute of Health (NIH) standards and serve as important references for practicing physicians.


      Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

      Organizations Supporting this Disease

        Learn more

        These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

        Where to Start

          In-Depth Information

          • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
          • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.


            1. Neuroendocrine Tumors. Mayo Clinic. August 18, 2017; https://www.mayoclinic.org/diseases-conditions/neuroendocrine-tumors/symptoms-causes/syc-20354132.
            2. Neuroendocrine Tumor: Introduction. Cancer.Net, American Society of Clinical Oncology. November, 2016; https://www.cancer.net/cancer-types/neuroendocrine-tumor/introduction.
            3. Background: Neuroendocrine tumor/carcinoid tumor features. American Association of Endocrine Surgeons. https://endocrinediseases.org/neuroendocrine/neuroendocrine_background.shtml. Accessed 4/30/2018.
            4. Newly Diagnosed: The Basics. The Carcinoid Cancer Foundation. https://www.carcinoid.org/for-patients/diagnosis/newly-diagnosed-the-basics/. Accessed 2/13/2018.
            5. Carcinoid Tumor. Cancer.Net, American Society of Clinical Oncology. August, 2016; https://www.cancer.net/cancer-types/carcinoid-tumor/introduction.
            6. Pancreatic Neuroendocrine Tumors (Islet Cell Tumors) Treatment (PDQ®)–Patient Version. National Cancer Institute. March 22, 2018; https://www.cancer.gov/types/pancreatic/patient/pnet-treatment-pdq.
            7. Pancreatic Neuroendocrine Tumors. Neuroendocrine Tumor Research Foundation (NETRF). https://netrf.org/about-neuroendocrine-tumors/net-tests-treatments/common-neuroendocrine-tumor-sites/understanding-pancreatic-nets/. Accessed 4/25/2019.
            8. Neuroendocrine Tumor: Treatment Options. Cancer.Net (American Society of Clinical Oncology). November, 2016; https://www.cancer.net/cancer-types/neuroendocrine-tumor/treatment-options.
            9. Surgery. Neuroendocrine Tumor Research Foundation (NETRF). https://netrf.org/about-neuroendocrine-tumors/net-tests-treatments/net-treatment-options/net-surgery-options/. Accessed 4/25/2019.
            10. Interventional Radiology as a Treatment for Neuroendocrine Tumors. Neuroendocrine Tumor Research Foundation (NETRF). https://netrf.org/about-neuroendocrine-tumors/net-tests-treatments/net-treatment-options/interventional-radiology/. Accessed 4/25/2019.