Causes, incidence, and risk factors:

• The cause is unknown, but genetic factors play a role in some cases.

• Risk factors include a family history of multiple endocrine neoplasia type I (MEN I).

• Glucagonoma is usually malignant (cancerous).

• The cancer tends to spread and get worse.

• The cancer affects the islet cells of the pancreas.

• As a result, they produce too much of a hormone called glucagon.

• The excess glucagon causes symptoms such as glucose intolerance and hyperglycemia (elevated blood sugar).

• Glucagonoma also cause a distinctive skin lesion called necrolytic migratory erythema.

 Symptoms:

• Diarrhoea
• Skin rash that migrates on face, abdomen, perineum, buttocks, or lower extremities

                    o May be crusty or scaly
                    o May be raised lesions filled with clear fluid or pus

• Inflamed mouth and tongue
• Unintentional weight loss
• Increased appetite
• Excess thirst
• Frequent urination
• Nocturnal (nighttime) urination
• Increased appetite

Signs and tests:

 Signs include:

• Glucose intolerance
• High blood sugar (hyperglycemia)

 Tests:

• Higher than normal serum glucagon level
• Pancreatic tumor revealed by CT scan
• Higher than normal fasting glucose level
• Abnormal glucose tolerance test

Treatment:

•  Surgical removal of the tumor is the preferred treatment. The tumor does not respond to chemotherapy.

 Prognosis:

• Approximately 60% of these tumors are cancerous.
  
• If the tumor is only in the pancreas and surgery to remove it is successful,  patients have a 5-year survival rate of 85%.

Complication:

• Metastasis of cancer to the liver is a complication.