How Does Pancreatic Neuroendocrine Tumor Affect the Body?

Nonfunctioning neuroendocrine tumors are pancreatic tumors that begin in the neuroendocrine cells of the pancreas but do not produce hormones. Hence, a person may not experience symptoms for a long time unless the tumor becomes large enough and puts pressure on the surrounding structures, such as the bile duct.

When symptoms do occur, they may include:

• Yellowing on the skin or whites of the eyes (jaundice)
• Diarrhea
• Upset stomach
• Nausea
• Loss of appetite
• Pain in the abdomen or back
• Lump in the abdomen

A functioning neuroendocrine tumor of the pancreas produces excess hormones. Depending on the type of cells secreting the hormones, different types of functioning neuroendocrine tumors can form.

Gastrinoma

Gastrin is a hormone that helps digest food by stimulating the production of stomach acid. When a tumor develops in gastrin-producing cells, it is called gastrinoma, with symptoms such as:

• Ulcers (due to too much stomach acid)
• Diarrhea

Insulinoma

They begin in the cells that make insulin. Because of these excess abnormal cells, a higher level of insulin is secreted, which can cause frequent episodes of hypoglycemia (a condition in which blood sugar level becomes low). It can result in symptoms that include:

• Fatigue
• Nervousness
• Shakiness
• Dizziness or lightheadedness
• Seizures
• Fainting episodes
• Confusion
• Anxiety
• Mood swings
• Blurred vision

Glucagonoma

Glucagon increases the amount of glucose present in the blood. A glucagonoma forms from a group of glucagon-producing cells. It causes hyperglycemia, which is a condition characterized by high blood sugar levels, and may result in symptoms such as:

• Frequent urination
• Increased thirst
• Increased hunger

A rash that spreads on the face, abdomen, or lower extremities may also result from glucagonoma.

Verner–Morrison syndrome (VIPoma)

VIPomas produce too many vasoactive intestinal peptides (VIP), which are involved in the regulation of water and electrolyte levels in the body. Its symptoms include:

• Watery diarrhea
• Irregular heartbeat
• Muscle cramping
• Muscle weakness
• Issues with digestion
• Poor absorption of vitamins and nutrients
• Flushing or redness of the face, neck, or chest
• Fatigue
• Nausea

Somatostatinoma

Somatostatinomas are extremely rare and large tumors that produce somatostatin. Somatostatin maintains the balance of gastrointestinal hormones by regulating their secretion.

Symptoms of a somatostatinoma include:

• Diarrhea
• Gallstones
• Jaundice (yellowing of the skin or eyes)
• Unexplained weight loss
• Weakness
• Hunger
• Confusion
• Headaches
• Frequent urination
• Dry skin

Remember, if experiencing two or more of these symptoms, it may not necessarily be a pancreatic neuroendocrine tumor. These symptoms are also found in other medical conditions. If concerned about any changes, schedule an appointment with your doctor to discuss your symptoms.