Pancreatic islet cell tumor
A pancreatic islet cell tumor is a rare tumor of the pancreas that starts from a type of cell called the islet cell.
Islet cell tumors; Islet of Langerhans tumor; Neuroendocrine tumors
Causes, incidence, and risk factors
In the normal pancreas, cells called islet cells produce hormones that regulate a variety of bodily functions, such as blood sugar level and the production of stomach acid.
Tumors that arise from islet cells of the pancreas can also produce a variety of hormones, though some do not.
Although islet cells produce many different hormones, most tumors release only one hormone that leads to specific symptoms. Pancreatic islet cell tumors can be noncancerous (benign) or cancerous (malignant).
Islet cell tumors include:
- Gastrinomas (Zollinger-Ellison syndrome)
Symptoms are caused by the hormone the tumor is producing.
For example, insulinomas produce the hormone insulin, which helps the body lower blood sugar levels. Symptoms may include:
- Feeling tired or weak
- Shaking or sweating
- Nervousness, anxiety, or feeling irritable
- Unclear thinking or feeling uneasy
- Double or blurry vision
- Fast or pounding heartbeat
If your blood sugar gets too low, you may faint, have a seizure, or even go into a coma.
Gastrinomas make the hormone gastrin, which helps the body manage stomach acid. Symptoms may include:
- Abdominal pain
- Ulcers in the stomach and small bowel
- Vomiting blood (occasionally)
Glucagonomas make the hormone glucagon, which helps the body raise blood sugar levels. Symptoms can include:
- Diabetes (present in most of the patients)
- Inflamed mouth and tongue
- Crusty or scaly skin rash on the face, abdomen, buttocks, or feet - may be filled with clear fluid or pus
Signs and tests
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 insulin C-peptide
- Blood insulin level
The following imaging tests may be performed:
Other tests that may be done include:
Sampling the vein drainage of segments of the pancreas
Occasionally, surgery is needed to diagnose and treat this condition. During this procedure, the surgeon feels the pancreas and may use ultrasound probes.
Treatment will depend on the type of tumor and whether the tumor is noncancerous (benign) or cancerous (malignant). Malignant tumors can spread to other organs, grow aggressively, and may not be treatable. Tumors are usually removed with surgery, if possible.
If malignant cancer cells spread (metastasize) to the liver, a portion of the liver may also be removed, if possible. If the cancer is widespread, various forms of chemotherapy may be used to try and shrink the tumors.
If the abnormal production of hormones is causing problems, you may receive medications to counteract their effects. For example, with gastrinomas, the overproduction of gastrin leads to too much acid in the stomach. Medications that block acid release can reduce symptoms.
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 patients.
Life-threatening problems (such as very low blood sugar) can occur due to excess hormone production, or if the cancer spreads throughout the body.
- 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
Calling your health care provider
Call your health care provider if you develop symptoms of these tumors, especially if you have a family history of MEN I.
There is no known prevention for these tumors.
National Comprehensive Cancer Network Clinical Practice Guidelines in Oncology: Neuroendocrine Tumors. National Comprehensive Cancer Network; 2009. Version 2.2009.
Jensen RT. Pancreatic endocrine tumors. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 205.
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.