Treatment

The treatment of an islet cell tumor depends on the size and location of the tumor, whether it is cancerous, whether the cancer has spread, and the person's overall health. In many cases, a team of doctors may work with the patient to determine the best treatment plan.

This section outlines treatments that are the standard of care (the best treatments available) for this specific type of cancer. Patients are also encouraged to consider clinical trials as a treatment option when making treatment plan decisions. A clinical trial is a research study to test a new treatment to prove it is safe, effective, and possibly better than standard treatment. Your doctor can help you review all treatment options. For more information, visit the clinical trials section.

Active Surveillance

Sometimes, an active surveillance (also called watchful waiting or watch and wait) approach without any active treatment may be recommended, as these tumors can often be quite indolent (non-aggressive) and not grow, spread, or cause problems for many months or even years. With this approach, the patient is monitored closely with regular CT scans and physical exams to determine if the tumor is growing. If the tumor shows signs of growing or becoming aggressive, active treatment would then begin.

Surgery

Surgery is the most common treatment for an islet cell tumor that is localized (has not spread outside of the pancreas). During surgery, the doctor may need to remove most or part of the pancreas, depending on the location and size of the tumor. For a gastrinoma, it may also be necessary to take out the stomach to remove ulcers, a procedure called a gastrectomy. The spleen may also need to be removed in a procedure called a splenectomy. Sometimes, an operation referred to as a Whipple procedure may be required. During a Whipple procedure, the surgeon removes the head of the pancreas and part of the small intestine, bile duct, and stomach, and then reconnects the digestive tract and biliary system.

Side effects of surgery include weakness, fatigue, and pain the first few days following the procedure. The doctor may prescribe medication to help manage these side effects. The patient will need to stay in the hospital for several days and will probably need to rest at home for about one month. It may be difficult to digest food due to the removal of all or part of the pancreas. A special diet and medicine may help. Also, the doctor can prescribe hormones and enzymes to replace those lost by the removal of the pancreas. Another side effect is the development of diabetes due to the loss of insulin, which is produced by the pancreas. Therefore, the doctor may need to prescribe insulin.

Hormone therapy

Hormone therapy may be given to relieve symptoms caused by the tumor. The most common hormone used is octreotide (Sandostatin), which is similar to one of the hormones normally produced by the body, somatostatin. The idea is that many islet cell tumors express (on their cell surface) receptors to somatostatin. Octreotide can be given either as daily injections under the skin or intramuscularly (into a muscle) on a monthly basis (called Sandostatin LAR Depot). Common side effects of octreotide include gallbladder abnormalities (gallstones and/or biliary sludge) and gastrointestinal problems, such as diarrhea and abdominal discomfort.

Chemotherapy

Chemotherapy is the use of drugs to kill cancer cells. Systemic chemotherapy is delivered through the bloodstream, targeting cancer cells throughout the body. Chemotherapy may be given intravenously (through a vein) or orally (by mouth). The side effects of chemotherapy depend on the individual and the dose used, but can include fatigue, risk of infection, nausea and vomiting, loss of appetite, and diarrhea. These side effects usually go away once treatment is finished.

The medications used to treat cancer are continually being evaluated. Talking with your doctor is often the best way to learn about the medications you've been prescribed, their purpose, and their potential side effects or interactions with other medications. Learn more about your prescriptions through Cancer.Net's Drug Information Resources, which provides links to searchable drug databases.

Immunotherapy

Immunotherapy (also called biologic therapy) is designed to boost the body's natural defenses to fight the cancer. It uses materials either made by the body or in a laboratory to bolster, target, or restore immune system function. Alpha interferon is a form of immunotherapy given as injections under the skin, and is sometimes used to help relieve symptoms caused by the tumor, but it can have significant side effects including fatigue, depression, and flu-like symptoms.

Hepatic artery occlusion or embolization

Generally used for patients with liver metastases (spread to the liver), these procedures block the tumor’s blood supply by temporarily sealing off the blood vessels leading to the tumor. They are usually performed by a skilled interventional radiologist and require an inpatient hospital stay. Side effects of the procedure include pain around the liver, fever, and temporary higher levels of liver enzymes as measured by blood tests. Whether this procedure is suitable for a patient depends on the size and number of tumor(s) and the location of the tumor(s) within the liver. The effectiveness of chemotherapy combined with hepatic artery embolization is still being studied.

To learn about the terms used in this section, read the Cancer.Net Feature: Cancer Terms to Know: During Treatment.