Pancreatic Neuroendocrine Tumor

Pancreatic neuroendocrine tumor form in hormone-making cells (islet cells) of the pancreas. The pancreas is a gland about 6 inches long that is shaped like a thin pear lying on its side. The wider end of the pancreas is called the head, the middle section is called the body, and the narrow end is called the tail. The pancreas lies behind the stomach and in front of the spine.

There are two kinds of cells in the pancreas:

  • Endocrine pancreas cells make several kinds of hormones (chemicals that control the actions of certain cells or organs in the body), such as insulin to control blood sugar. They cluster together in many small groups (islets) throughout the pancreas. Endocrine pancreas cells are also called islet cells or islets of Langerhans. Tumors that form in islet cells are called islet cell tumors, pancreatic endocrine tumors, or pancreatic neuroendocrine tumors (pancreatic NETs).
  • Exocrine pancreas cells make enzymes that are released into the small intestine to help the body digest food. Most of the pancreas is made of ducts with small sacs at the end of the ducts, which are lined with exocrine cells.

Pancreatic Neuroendocrine Tumor Risk

Multiple endocrine neoplasia type 1 (MEN1) syndrome is a risk factor for pancreatic NETs.


Pancreatic NETs may be functional or nonfunctional:

  • Functional tumors make extra amounts of hormones, such as gastrin, insulin, and glucagon, that cause symptoms.
  • Nonfunctional tumors do not make extra amounts of hormones. Symptoms are caused by the tumor as it spreads and grows. Most nonfunctional tumors are malignant (cancer).

Most pancreatic NETs are functional tumors.

Signs and symptoms of a non-functional pancreatic NET:

  • Diarrhea
  • Indigestion
  • A lump in the abdomen
  • Pain in the abdomen or back
  • Yellowing of the skin and whites of the eyes

Signs and symptoms of a functional pancreatic NET depend on the type of hormone being made.

Too much gastrin may cause:

  • Stomach ulcers that keep coming back
  • Pain in the abdomen, which may spread to the back. 
  • The flow of stomach contents back into the esophagus (gastroesophageal reflux)
  • Diarrhea

Too much insulin may cause:

  • Low blood sugar
  • Fast heartbeat

Too much glucagon may cause:

  • Skin rash on the face, stomach, or legs
  • High blood sugar
  • Blood clots
  • Diarrhea
  • Weight loss for no known reason
  • Sore tongue or sores at the corners of the mouth

Too much vasoactive intestinal peptide (VIP) may cause:

  • Very large amounts of watery diarrhea
  • Dehydration
  • Low potassium level in the blood
  • Cramps or pain in the abdomen
  • Weight loss for no known reason

Too much somatostatin may cause:

  • High blood sugar. This can cause headaches, frequent urination, dry skin and mouth, or feeling hungry, thirsty, tired, or weak.
  • Diarrhea
  • Steatorrhea (very foul-smelling stool that floats)
  • Gallstones
  • Yellowing of the skin and whites of the eyes
  • Weight loss for no known reason

Pancreatic Neuroendocrine Tumor Diagnosis

The following tests and procedures may be used:

  • Physical exam and history
  • Blood chemistry studies
  • Chromogranin A test
  • Abdominal CT scan (CAT scan)
  • MRI (magnetic resonance imaging)
  • Somatostatin receptor scintigraphy
  • Endoscopic ultrasound (EUS)
  • Endoscopic retrograde cholangiopancreatography (ERCP)
  • Angiogram 
  • Laparotomy 
  • Intraoperative ultrasound 
  • Biopsy
  • Bone scan

The following tests and procedures may be used to diagnose Pancreatic Neuroendocrine Tumor:

  • Gastrinoma
    • Fasting serum gastrin test
    • Basal acid output test
    • Secretin stimulation test
    • Somatostatin receptor scintigraphy
  • Insulinoma
    • Fasting serum glucose and insulin test
  • Glucagonoma
    • Fasting serum glucagon test

Other tumor types

  • VIPoma
    • Serum VIP (vasoactive intestinal peptide) test
    • Blood chemistry studies
    • Stool analysis 
    • Somatostatinoma
      • Fasting serum somatostatin test
      • Somatostatin receptor scintigraphy


Six types of standard treatment are used for Pancreatic Neuroendocrine Tumor:

  • Surgery
    • Enucleation
    • Pancreatoduodenectomy
    • Distal pancreatectomy
    • Total gastrectomy
    • Parietal cell vagotomy
    • Radiofrequency ablation
    • Cryosurgical ablation
  • Chemotherapy
  • Hormone therapy
  • Hepatic arterial occlusion or chemoembolization
  • Targeted therapy
  • Supportive care
    • Stomach ulcers may be treated with drug therapy such as:
      • Proton pump inhibitor drugs such as omeprazole, lansoprazole, or pantoprazole.
      • Histamine blocking drugs such as cimetidine, ranitidine, or famotidine.
      • Somatostatin-type drugs such as octreotide.
      • Diarrhea may be treated with:
        • Intravenous (IV) fluids with electrolytes such as potassium or chloride.
        • Somatostatin-type drugs such as octreotide.
        • Low blood sugar may be treated by having small, frequent meals or with drug therapy to maintain a normal blood sugar level.
        • High blood sugar may be treated with drugs taken by mouth or insulin by injection.


Content was created using EBSCO’s Health Library. Edits to original content made by Rector and Visitors of the University of Virginia. This information is not a substitute for professional medical advice.