General Information About Gastrointestinal Stromal Tumors (GIST)

General Information About Gastrointestinal Stromal Tumors (GIST)

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General Information About Gastrointestinal Stromal Tumors

KEY POINTS

• Gastrointestinal stromal tumor is a disease in which abnormal cells form in the tissues of the gastrointestinal tract.
• Genetic factors can increase the risk of having a gastrointestinal stromal tumor.
• Signs of gastrointestinal stromal tumors include blood in the stool or vomit.
• Tests that examine the GI tract are used to detect (find) and diagnose gastrointestinal stromal tumors.
• Very small GISTs are common.
• Certain factors affect prognosis (chance of recovery) and treatment options.

Gastrointestinal stromal tumor is a disease in which abnormal cells form in the tissues of the gastrointestinal tract.

The gastrointestinal (GI) tract is part of the body’s digestive system. It helps to digest food and takes nutrients(vitamins, minerals, carbohydrates, fats, proteins, and water) from food so they can be used by the body. The GI tract is made up of the following organs:

• Stomach.
• Small intestine.
• Large intestine (colon).

Gastrointestinal stromal tumors (GISTs) may be malignant (cancer) or benign (not cancer). They are most common in the stomach and small intestine but may be found anywhere in or near the GI tract. Somescientists believe that GISTs begin in cells called interstitial cells of Cajal (ICC), in the wall of the GI tract.

ENLARGE

Gastrointestinal stromal tumors (GISTs) may be found anywhere in or near the gastrointestinal tract.

See the PDQ summary about Unusual Cancers of Childhood Treatment for information on the treatment of GIST in children.

Genetic factors can increase the risk of having a gastrointestinal stromal tumor.

Anything that increases your risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn't mean that you will not get cancer. Talk with your doctor if you think you may be at risk.

The genes in cells carry the hereditary information received from a person’s parents. The risk of GIST is increased in people who have inherited a mutation (change) in a certain gene. In rare cases, GISTs can be found in several members of the same family.

GIST may be part of a genetic syndrome, but this is rare. A genetic syndrome is a set of symptoms or conditionsthat occur together and is usually caused by abnormal genes. The following genetic syndromes have been linked to GIST:

• Neurofibromatosis type 1 (NF1).
• Carney triad.

Signs of gastrointestinal stromal tumors include blood in the stool or vomit.

These and other signs and symptoms may be caused by a GIST or by other conditions. Check with your doctor if you have any of the following:

• Blood (either bright red or very dark) in the stool or vomit.
• Pain in the abdomen, which may be severe.
• Feeling very tired.
• Trouble or pain when swallowing.
• Feeling full after only a little food is eaten.

Tests that examine the GI tract are used to detect (find) and diagnose gastrointestinal stromal tumors.

The following tests and procedures may be used:

• Physical exam and history : An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
• CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may beinjected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
• MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).
• Endoscopic ultrasound and biopsy : Endoscopy and ultrasound are used to make an image of the upper GI tract and a biopsy is done. An endoscope (a thin, tube-like instrument with a light and a lens for viewing) is inserted through the mouth and into the esophagus, stomach, and first part of the small intestine. A probe at the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal tissues or organs and make echoes. The echoes form a picture of body tissues called asonogram. This procedure is also called endosonography. Guided by the sonogram, the doctor removes tissue using a thin, hollow needle. A pathologist views the tissue under a microscope to look for cancer cells.

If cancer is found, the following tests may be done to study the cancer cells:

• Immunohistochemistry : A test that uses antibodies to check for certain antigens in a sample of tissue. The antibody is usually linked to a radioactive substance or a dye that causes the tissue to light up under a microscope. This type of test may be used to tell the difference between different types of cancer.
• Mitotic rate : A measure of how fast the cancer cells are dividing and growing. The mitotic rate is found by counting the number of cells dividing in a certain amount of cancer tissue.

Very small GISTs are common.

Sometimes GISTs are smaller than the eraser on top of a pencil. Tumors may be found during a procedure that is done for another reason, such as an x-ray or surgery. Some of these small tumors will not grow and cause signs or symptoms or spread to the abdomen or other parts of the body. Doctors do not agree on whether these small tumors should be removed or whether they should be watched to see if they begin to grow.

Certain factors affect prognosis (chance of recovery) and treatment options.

The prognosis (chance of recovery) and treatment options depend on the following:

• How quickly the cancer cells are growing and dividing.
• The size of the tumor.
• Where the tumor is in the body.
• Whether the tumor can be completely removed by surgery.
• Whether the tumor has spread to other parts of the body.

Next section >
Stages of Gastrointestinal Stromal Tumors

• Updated: July 28, 2015

*ref) http://www.cancer.gov/types/soft-tissue-sarcoma/patient/gist-treatment-pdq

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Treatments for GIST

Patients with gastrointestinal stromal tumor (GIST cancer) can receive effective treatments today.  For links to experts' treatment recommendations for GIST, see the NCCN and other expert consensus GIST standard-of-care guidelines listed on our page GIST Treatment Guidelines.

Current Treatments

• Surgery - Surgery is the first step in treatment for GIST, and it is often curative.
• Imatinib (Gleevec) - Imatinib (Gleevec) is FDA-approved for treatment of unresectable and metastatic GIST, as well as for prevention of recurrence of higher-risk GISTs (adjuvant therapy).
• Sunitinib (Sutent) - Sunitinib (Sutent) is FDA-approved for treatment of GIST resistant to imatinib/Gleevec and for patients who are intolerant of imatinib/Gleevec.
• Regorafenib (Stivarga) - Regorafenib (Stivarga) is approved for treatment of GIST resistant to imatinib and sunitinib. 
• Hepatic artery embolization - Embolization is a surgical procedure for treatment of liver metastases of GIST.
• Radiofrequency ablation - RFA is a surgical procedure for treatment of liver metastases of GIST.
• Off-Label Use of FDA-Approved Drugs - Drugs approved for other diseases that may be prescribed for GIST at a physician's discretion.
• GIST Patients' Right to Treatment - the Bad Nauheim Declaration, endorsed by GIST Support International, for the right of all GIST cancer patients to receive up-to-date treatment.

Emerging Treatments

• Emerging Treatments covers drugs in pre-clinical development and in clinical trials.

 

Clinical Trials

• Clinical Trials informs you about current trials for gastrointestinal stromal tumor plus things to consider before signing up for a trial.  This page includes a table showing all clinical trials for GIST, plus maps of locations of trials for GIST cancer.

*ref) http://www.gistsupport.org/treatments-for-gist.php

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