Lima Memorial Health System Logo
Approximate ER WAIT TIME WAIT TIME MACRO
Lima Memorial eHealth
Careers
Ways to Give

Health Library

Pancreatic neuroendocrine tumors
     
Print-Friendly
Bookmarks

Pancreatic neuroendocrine tumors

Cancer - pancreas; Cancer - pancreatic; Pancreatic cancer; Islet cell tumors; Islet of Langerhans tumor; Neuroendocrine tumors; Peptic ulcer - islet cell tumor; Hypoglycemia - islet cell tumor; Zollinger-Ellison syndrome; Verner-Morrison syndrome; Gastrinoma; Insulinoma; VIPoma; Somatostatinoma; Glucagonoma; Pancreatic islet cell tumor

 

Pancreatic neuroendocrine tumors (NET) are rare tumors of the pancreas that start from a type of cell called the islet cell.

Causes

 

In the healthy pancreas, cells called islet cells produce hormones that regulate several bodily functions. These include blood sugar level (regulated by insulin) and the production of stomach acid (regulated by gastrin).

Tumors that arise from islet cells of the pancreas can also produce a variety of hormones, which can lead to specific symptoms.

Pancreatic NETs can be noncancerous (benign) or cancerous (malignant).

NETs include:

  • Gastrinoma (Zollinger-Ellison syndrome)
  • Glucagonoma
  • Insulinoma
  • Somatostatinoma
  • VIPoma (Verner-Morrison syndrome)

A family history of multiple endocrine neoplasia, type I (MEN I) is a risk factor for the development of NETs.

 

Symptoms

 

Symptoms depend on which hormone is made by the tumor.

For example, insulinomas produce insulin, which lowers the blood sugar level. Symptoms may include:

  • Feeling tired or weak
  • Shaking or sweating
  • Headache
  • Hunger
  • Nervousness, anxiety, or feeling irritable
  • Unclear thinking or feeling uneasy
  • Double or blurry vision
  • Fast or pounding heartbeat

If your blood sugar level gets too low, you may faint, have a seizure, or even go into a coma.

Gastrinomas make the hormone gastrin, which tells the body to make stomach acid. Symptoms may include:

  • Abdominal pain
  • Diarrhea
  • Ulcers in the stomach and small bowel
  • Vomiting blood (occasionally)

Glucagonomas make the hormone glucagon, which helps the body raise blood sugar level. Symptoms can include:

  • Diabetes
  • Red, blistery rash in the groin or buttocks
  • Weight loss
  • Frequent urination and thirst

Somatostatinomas make the hormone somatostatin. Symptoms may include:

  • High blood sugar
  • Gallstones
  • Yellowish appearance to skin, and eyes
  • Weight loss
  • Diarrhea with foul smelling stools

VIPomas make the hormone vasoactive intestinal peptide (VIP) which is involved in maintaining the balance of sodium, potassium and other minerals in the GI tract. VIPomas may cause:

  • Severe diarrhea that may lead to dehydration
  • Low blood potassium levels, and high calcium levels
  • Abdominal cramps
  • Weight loss

 

Exams and Tests

 

Your health care provider will take your medical history and perform a physical exam.

Blood tests may vary, depending upon the symptoms, but may include:

  • Fasting glucose level
  • Gastrin level
  • Glucose tolerance test
  • Secretin stimulation test for pancreas
  • Blood glucagon level
  • Blood C-peptide level
  • Blood insulin level
  • Fasting serum somatostatin level
  • Serum vasoactive intestinal peptide (VIP) level

Imaging tests may be done:

  • Abdominal CT scan
  • Abdominal ultrasound
  • Endoscopic ultrasound
  • MRI of abdomen

A blood sample may also be taken from a vein in the pancreas for testing.

Sometimes, surgery is needed to diagnose and treat this condition. During this procedure, the surgeon examines the pancreas by hand and with ultrasound.

 

Treatment

 

Treatment depends on the type of tumor and if it is cancerous.

Cancerous tumors can grow quickly and spread to other organs. They may not be treatable. Tumors are often removed with surgery, if possible.

If cancer cells spread to the liver, a part of the liver may also be removed, if possible. If the cancer is widespread, chemotherapy may be used to try to shrink the tumors.

If the abnormal production of hormones is causing symptoms, you may receive medicines to counteract their effects. For example, with gastrinomas, the overproduction of gastrin leads to too much acid in the stomach. Medicines that block stomach acid release can reduce symptoms.

 

Support Groups

 

You can ease the stress of illness by joining a cancer support group. Sharing with others who have common experiences and problems can help you not feel alone.

 

Outlook (Prognosis)

 

You may be cured if the tumors are surgically removed before they have spread to other organs. If tumors are cancerous, chemotherapy may be used, but it usually cannot cure people.

Life-threatening problems (such as very low blood sugar) can occur due to excess hormone production, or if the cancer spreads throughout the body.

 

Possible Complications

 

Complications of these tumors include:

  • Diabetes
  • Hormone crises (if the tumor releases certain types of hormones)
  • Severe low blood sugar (from insulinomas)
  • Severe ulcers in the stomach and small intestine (from gastrinomas)
  • Spread of the tumor to the liver

 

When to Contact a Medical Professional

 

Contact your provider if you develop symptoms of these tumors, especially if you have a family history of MEN I.

 

Prevention

 

There is no known prevention for these tumors.

 

 

Open References

References

McVey JC, Vollmer CM, Roses RE. Management of pancreatic islet cell tumors excluding gastrinoma. In: Cameron JL, Cameron AM, eds. Current Surgical Therapy. 15th ed. Philadelphia, PA: Elsevier; 2026:chap 105.

National Cancer Institute website. Pancreatic neuroendocrine tumors (islet cell tumors) treatment (PDQ) - health professional version. www.cancer.gov/types/pancreatic/hp/pnet-treatment-pdq. Updated May 9, 2025. Accessed February 20, 2026.

National Comprehensive Cancer Network website. NCCN clinical practice guidelines in oncology (NCCN guidelines). Neuroendocrine and adrenal tumors. Version 3. 2025. www.nccn.org/professionals/physician_gls/pdf/neuroendocrine.pdf. Updated October 1, 2025. Accessed February 20, 2026.

National Comprehensive Cancer Network website. NCCN guidelines for patients. Neuroendocrine tumors. 2025. www.nccn.org/patients/guidelines/content/PDF/neuroendocrine-patient.pdf. Accessed February 23, 2026.

Nieman LK, Spiegel AM. Polyglandular disorders. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 212.

BACK TO TOPText only

 
  • Endocrine glands

    Endocrine glands

    illustration

  • Pancreas

    Pancreas

    illustration

    • Endocrine glands

      Endocrine glands

      illustration

    • Pancreas

      Pancreas

      illustration

    A Closer Look

     

      Tests for Pancreatic neuroendocrine tumors

       
         

        Review Date: 1/25/2026

        Reviewed By: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

        The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. No warranty of any kind, either expressed or implied, is made as to the accuracy, reliability, timeliness, or correctness of any translations made by a third-party service of the information provided herein into any other language.

        © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

        All content on this site including text, images, graphics, audio, video, data, metadata, and compilations is protected by copyright and other intellectual property laws. You may view the content for personal, noncommercial use. Any other use requires prior written consent from Ebix. You may not copy, reproduce, distribute, transmit, display, publish, reverse-engineer, adapt, modify, store beyond ordinary browser caching, index, mine, scrape, or create derivative works from this content. You may not use automated tools to access or extract content, including to create embeddings, vectors, datasets, or indexes for retrieval systems. Use of any content for training, fine-tuning, calibrating, testing, evaluating, or improving AI systems of any kind is prohibited without express written consent. This includes large language models, machine learning models, neural networks, generative systems, retrieval-augmented systems, and any software that ingests content to produce outputs. Any unauthorized use of the content including AI-related use is a violation of our rights and may result in legal action, damages, and statutory penalties to the fullest extent permitted by law. Ebix reserves the right to enforce its rights through legal, technological, and contractual measures.
        © 1997- adam.comAll rights reserved.