Glucagonoma is a very rare tumor of the islet cells of the pancreas, which release the hormones insulin and glucagon.

Causes

Glucagonoma is usually cancerous (malignant). The cancer tends to spread and get worse.

This cancer affects the islet cells of the pancreas. As a result, they produce too much of the hormone glucagon.

The cause is unknown, but genetic factors play a role in some cases. A family history of multiple endocrine neoplasia type I (MEN I) is a risk factor.

Symptoms

• Diarrhea
• Excess thirst
• Frequent urination
• Increased appetite
• Inflamed mouth and tongue
• Nighttime (nocturnal) urination
• Skin rash on face, abdomen, buttocks, or lower extremities that comes and goes, and moves around
  • May be crusty or scaly
  • May be raised sores (lesions) filled with clear fluid or pus
• Unintentional weight loss

Exams and Tests

Signs include:

• Glucose intolerance
• High blood sugar (hyperglycemia)

Most of the time the cancer has already spread to the liver when it is diagnosed.

Tests may include:

• CT scan
• Fasting glucose level
• Glucose tolerance test
• Serum glucagon

Treatment

Surgery to remove the tumor is the preferred treatment. The tumor does not respond to chemotherapy.

Outlook (Prognosis)

Approximately 60% of these tumors are cancerous. Spread to the liver is common.

If the tumor is only in the pancreas and surgery to remove it is successful, patients have a 5-year survival rate of 85%.

Possible Complications

The cancer can spread to the liver.

When to Contact a Medical Professional

Call your health care provider if you notice symptoms of glucagonoma.