Gastrointestinal stromal tumors (GISTS) happen when cells lining your digestive tract grow and divide in an uncontrolled way, creating a mass of tissue called a tumor. GISTs can be cancerous. Some people with GIST may not notice changes in their health, while others may feel unwell or have pain or bleeding.
Gastrointestinal stromal tumors (GISTs) are rare tumors that occur when cells become abnormal and grow out of control. GISTs can start anywhere in your digestive (gastrointestinal) tract, from the esophagus to the anus. More than half start in the stomach, and most others start in the small intestine.
Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
GISTS are very rare in people under 40 years old. Some GISTs occur spontaneously, while others run in families. Talk to your healthcare provider if you have a family history of this condition.
The actual number of people with GIST is not known. However, the condition is rare. Healthcare providers estimate that there are between 4,000 and 6,000 cases per year in the U.S.
GISTs are uncommon tumors that can grow anywhere in your digestive tract , from the esophagus to the anus. Some GISTs are small and not harmful, while others may be larger or cancerous. While some people may have no symptoms, others may feel unwell or have pain or bleeding.
All of your body's cells normally grow, divide, and then die to keep your body healthy and functioning properly. Sometimes this process gets out of control. Cells keep growing and dividing even when they are supposed to die. When the cells lining your digestive tract multiply uncontrolled, GISTs may ultimately develop.
Most GISTs involve changes (mutations) in the KIT oncogene. This gene tells cells to make a protein (KIT CD117), which causes them to grow faster and divide.
Most GISTs are the result of spontaneous changes in your cells and are not inherited. However, certain inherited tumor disorders can increase your risk. These include familial GIST syndrome, neurofibromatosis type 1 and Carney-Stratakis syndrome. Talk to your healthcare provider if these or any similar conditions run in your family.
Some people have no symptoms of gastrointestinal stromal tumors (GISTs). Instead, their tumors are found accidentally during testing or surgery for another reason. Other individuals may experience the following symptoms:
Your healthcare provider will first obtain a medical history, physical exam and blood work. If GIST is suspected, your provider will order imaging or endoscopy to determine if it is cancer or another condition.
There are several tests your provider can do to diagnose your gastrointestinal stromal tumor. These tests might include:
GIST diagnosis and treatment are best accomplished by a team of experts working together with you. Each person needs to evaluate the advantages and limitations of each type of treatment. You’ll work with your team of physicians to develop the best approach.
After arriving at a cancer diagnosis, healthcare providers often try to figure out if your cancer has spread. Knowing how much cancer is in your body can help to determine how to treat it.
Cancer staging can be complicated. It’s a good idea to ask your provider to explain what it means for you.
For adults with GIST, providers use the American Joint Committee on Cancer (AJCC) TNM system. The AJCC TNM system is based on four factors:
The type of treatment your doctor recommends will depend on the size and location of your GIST, the results of lab tests and the stage of your disease. Your doctor will usually consider your age and general health, as well as your feelings about the treatment options. Treatment for GIST may include surgery and/or targeted drug therapy. Other therapies, such as chemotherapy and radiation therapy, are used less often.
Some GISTs can be cured by surgery. However, some tumors are too large or have spread to other areas where surgery alone would not be curative. In these situations, a targeted drug therapy called imatinib may be prescribed. This is a pill taken once or twice daily by mouth. It works by attaching to the KIT protein (associated with the growth of most GISTs) and blocking its ability to let cancer cells grow. This medication can shrink the tumor or keep it from growing in about 85% of patients. Sometimes, if your tumor shrinks enough, surgery may become a treatment option. Unfortunately, your tumor may become resistant to imatinib and may start to grow again. If this happens to you, other targeted drugs may work to shrink the GIST. These include sunitinib, regorafenib and ripretinib.
Whether you receive surgery or medication, your doctor will likely monitor your condition with CT scans every three to six months. Sometimes, PET scans are done to check your response to treatment.
The most common side effects of targeted therapy include:
Your cancer team will monitor you closely during treatment. It’s important to tell your provider if you have changes in your health during or after cancer treatment.
There are few known risk factors for GIST. Some GISTs develop because of spontaneous changes in cells. Known risk factors for GISTs are being 50 years old and older, and specific tumor disorders, including:
While the risk for some cancers can be lowered by healthy lifestyle changes (such as cutting back on alcohol, quitting smoking, or maintaining a healthy weight), no known lifestyle factors contribute to your risk of GIST. Talk to your healthcare provider if you have any of the known tumor disorders that can increase your risk of GISTs.
The National Cancer Institute reports that the five-year relative survival rate for GIST is 83%. That means 83% of people diagnosed with GIST are alive five years later. The rate is even higher when the GIST is localized and hasn’t spread to other areas of the body. Then the survival rate reaches as high as 93%. However, if the GIST has spread to distant locations in the body, the five-year survival rate is 55%. Treatments continue to improve, along with survival rates.
The outlook for people with GIST has improved dramatically in the last 20 years. In some patients, surgery may be curable. In others, targeted drug therapy with Tyrosine kinase inhibitors (a therapy that blocks signals needed for tumors to grow) may be necessary to shrink the tumor so it can be removed in surgery, slow its growth or help prevent it from spreading.
It’s normal to have questions about your health, especially if you have a cancer diagnosis. It can be helpful to write down your questions and take the list with you when you meet your doctor. Talk about any concerns you have about your health, cancer surgery or treatment. Common questions include:
Smoking can increase the chances of getting cancer at the same site or a different site.
Drinking alcohol increases the risk of certain cancers.
Eating well and staying active can help you reach a healthy weight and stay there. A healthy and balanced diet is important for overall wellness. This includes eating fruits, vegetables, whole grains and protein. Talk with your healthcare provider or a dietitian to find out about any special dietary needs that you may have. You could also ask if you should talk to a nutritionist for guidance on eating a healthy diet.
Research suggests that staying active after cancer may help lower the risk of recurrence and lead to longer survival. In addition, moderate exercise (walking, biking, swimming) for about 30 minutes every — or almost every — day can:
It’s important to start an exercise program slowly and increase activity over time. Some people may need to take special care in exercising. Talk with your provider before you begin any exercise program, and work with your provider or a specialist (such as a physical therapist) if needed. If you need to stay in bed during your recovery, even doing small activities can help. Stretching or moving your arms or legs can help you stay flexible and relieve muscle tension.
After cancer treatment ends, all cancer survivors should have follow-up care. Follow-up care for GIST means seeing a healthcare provider for regular medical checkups once you're finished with treatment. These checkups may include bloodwork and other tests and procedures that look for any changes in your health or any problems that may occur due to your cancer treatment.
These visits are also a time to check for physical and emotional problems that may develop months or years after treatment ends. Your follow-up care plan, along with a summary of your cancer treatment, is part of what is called a survivorship care plan. This plan will have all the information for you and your doctor to discuss to ensure that you get regular and thorough care after your treatment ends. Please note that it’s important that you continue to receive your routine care from your primary care provider in addition to follow-up cancer care.
A note from Cleveland Clinic
GISTs are rare tumors that can start anywhere in the intestinal tract. Some GISTs may cause bleeding, stomach pain or bloating. Other GISTs cause no symptoms and are detected accidentally during a procedure for another condition. Some GISTs are cancerous, but with treatment, the outlook is promising. It’s important to pay close attention to your body and let your doctor know if anything unusual happens.
If you are diagnosed with GIST, remember that you are not alone. You have your family and friends, and there are support groups for nearly every type of cancer. Ask your doctor for information about these groups. You can also contact your local chapter of the American Cancer Society for more information. In addition, your doctor can refer you to a social worker or a mental health professional, both of whom can help you deal with the emotional aspects of your diagnosis. The social worker can also help you with the practical and financial issues related to the disease.
Last reviewed by a Cleveland Clinic medical professional on 08/23/2021.
Learn more about our editorial process.