Pancreatic Cancer

General Information | Treatment Options | Islet Cell Tumors
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Islet Cell Tumors
  • About
  • Stages & Types
  • Treatment Options

What are islet cell tumors?

An islet cell tumor is a mass of abnormal cells that forms in the endocrine (hormone-producing) tissues of the pancreas. Islet cell tumors may be benign (noncancer) or malignant (cancerous). Islet cell cancer is rare.

The pancreas is about 6 inches long and is shaped like a thin pear, wider at one end and narrower at the other. The pancreas lies behind the stomach, inside a loop formed by part of the small intestine. The broader right end of the pancreas is called the head, the middle section is called the body, and the narrow left end is the tail.

The pancreas has two basic jobs in the body. It produces digestive juices that help break down (digest) food, and hormones (such as insulin) that regulate how the body stores and uses food. The area of the pancreas that produces digestive juices is called the exocrine pancreas. About 95% of pancreatic cancers begin in the exocrine pancreas. The hormone-producing area of the pancreas has special cells called islet cells and is called the endocrine pancreas. Only about 5% of pancreatic cancers start here. This summary has information on cancer of the endocrine pancreas (islet cell cancer). (See the PDQ summary on Pancreatic Cancer Treatment for more information on cancer of the exocrine pancreas.)

The islet cells in the pancreas make many hormones, including insulin, which help the body store and use sugars. When islet cells in the pancreas become cancerous, they may make too many hormones. Islet cell cancers that make too many hormones are called functioning tumors. Other islet cell cancers may not make extra hormones and are called nonfunctioning tumors. Tumors that do not spread to other parts of the body can also be found in the islet cells. These are called benign tumors and are not cancer. A doctor will need to determine whether the tumor is cancer or a benign tumor.

A doctor should be seen if there is pain in the abdomen, diarrhea, stomach pain, a tired feeling all the time, fainting, or weight gain without eating too much.

If there are symptoms, the doctor will order blood and urine tests to see whether the amounts of hormones in the body are normal. Other tests, including x-rays and special scans, may also be done.

The chance of recovery (prognosis) depends on the type of islet cell cancer the patient has, how far the cancer has spread, and the patient's overall health.

For more information from the National Cancer Institute about islet cell tumors (endocrine pancreas), see the Islet Cell Tumors Home Page.

Stages of islet cell cancer

Once islet cell cancer is found, more tests will be done to find out if cancer cells have spread to other parts of the body. This is called staging. The staging system for islet cell cancer is still being developed. These tumors are most often divided into one of three groups:

  1. islet cell cancers occurring in one site within the pancreas,
  2. islet cell cancers occurring in several sites within the pancreas, or
  3. islet cell cancers that have spread to lymph nodes near the pancreas or to distant sites.

Treatment of islet cell cancer depends on the type of tumor, the stage, and the patient's general health. The following types of islet cell tumors are found:

Gastrinoma

The tumor makes large amounts of a hormone called gastrin, which causes too much acid to be made in the stomach. Ulcers may develop as a result of too much stomach acid.

Insulinoma

The tumor makes too much of the hormone insulin and causes the body to store sugar instead of burning the sugar for energy. This causes too little sugar in the blood, a condition called hypoglycemia.

Glucagonoma

This tumor makes too much of the hormone glucagon and causes too much sugar in the blood, a condition called hyperglycemia.

Miscellaneous

Other types of islet cell cancer can affect the pancreas and/or small intestine. Each type of tumor may affect different hormones in the body and cause different symptoms.

Recurrent

Recurrent disease means that the cancer has come back (recurred) after it has been treated. It may come back in the pancreas or in another part of the body.

How islet cell cancer is treated

Different types of treatment are available for patients with islet cell cancer. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.

Three types of standard treatment are used:

  • Surgery (taking out the cancer).
  • Chemotherapy (using drugs to kill cancer cells).
  • Hormone therapy (using hormones to stop cancer cells from growing).

Surgery is the most common treatment of islet cell cancer. The doctor may take out the cancer and most or part of the pancreas. Sometimes the stomach is taken out (gastrectomy) because of ulcers. Lymph nodes in the area may also be removed and looked at under a microscope to see if they contain cancer.

Chemotherapy uses drugs to kill cancer cells. Chemotherapy may be taken by pill, or it may be put into the body by a needle in the vein or muscle. Chemotherapy is called a systemic treatment because the drug enters the bloodstream, travels through the body, and can kill cancer cells throughout the body.

Hormone therapy uses hormones to stop the cancer cells from growing or to relieve symptoms caused by the tumor.

Hepatic arterial occlusion or embolization uses drugs or other agents to reduce or block the flow of blood to the liver in order to kill cancer cells growing in the liver.

Treatment in a clinical trial

For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.

Many of today's standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.

Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.

Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.

Clinical trials are taking place in many parts of the country. In the following lists of treatments for the different types of islet cell tumors, a link to search results for current clinical trials is included for each section. These have been retrieved from NCI's clinical trials database. For some types of islet cell tumors, there may not be any trials listed. Check with your doctor for clinical trials that are not listed here but may be right for you.

Gastrinoma

Treatment may be one of the following:

  1. Surgery to remove the cancer.
  2. Surgery to remove the stomach (gastrectomy).
  3. Surgery to cut the nerve that stimulates the pancreas.
  4. Chemotherapy.
  5. Hormone therapy.
  6. Hepatic arterial occlusion or embolization to kill cancer cells growing in the liver.

Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with gastrinoma.

Insulinoma

Treatment may be one of the following:

  1. Surgery to remove the cancer.
  2. Chemotherapy.
  3. Hormone therapy.
  4. Drugs to relieve symptoms.
  5. Hepatic arterial occlusion or embolization to kill cancer cells growing in the liver.

Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with insulinoma.

Glucagonoma

Treatment may be one of the following:

  1. Surgery to remove the cancer.
  2. Chemotherapy.
  3. Hormone therapy.
  4. Hepatic arterial occlusion or embolization to kill cancer cells growing in the liver.

Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with glucagonoma.

Miscellaneous Islet Cell Tumors

Treatment may be one of the following:

  1. Surgery to remove the cancer.
  2. Chemotherapy.
  3. Hormone therapy.
  4. Hepatic arterial occlusion or embolization to kill cancer cells growing in the liver.

Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with islet cell tumor.

Recurrent Islet Cell Tumors

Treatment depends on many factors, including what treatment the patient had before and where the cancer has come back. Treatment may be chemotherapy, or patients may want to consider taking part in a clinical trial.

Check for U.S. clinical trials from NCI's PDQ Cancer Clinical Trials Registry that are now accepting patients with recurrent islet cell carcinoma.

 

Cancer information from the NCI PDQ service