Gastrointestinal stromal tumors (GISTs) are tumors of the digestive tract that most often occur in the stomach or upper part of the small intestine. GISTs also may be found in the esophagus, large intestine and anus. GISTs occur most often in middle-aged and older adults. GISTs are rare in children. GISTs start in the cells of your digestive tract that send signals that cause digestive organs to contract. These contractions help move food and liquids through your digestive system.

  • Mayo Clinic doctors diagnose and treat a wide spectrum of digestive system cancers, including gastrointestinal stromal tumors. Specialists in digestive tract diseases (gastroenterologists), cancer (oncologists), surgery, rehabilitation, pathology (pathologists) and other specialties care for people with GISTs.
  • Many Mayo Clinic oncologists and surgeons belong to the Mayo Clinic Cancer Center, a multidisciplinary research group. The National Cancer Institute has designated the Mayo Clinic Cancer Center as a comprehensive cancer center due, in part, to its depth and breadth of sarcoma research.

Mayo Clinic in Rochester, Minn., Mayo Clinic in Jacksonville, Fla., and Mayo Clinic in Scottsdale, Ariz., are ranked among the Best Hospitals for cancer by U.S. News & World Report.

To identify gastrointestinal stromal tumors (GISTs), Mayo Clinic doctors perform a comprehensive physical exam. This exam may include imaging studies of the tumor, blood tests, endoscopy and biopsies.

Imaging studies may include:

  • X-rays. X-rays generate one-dimensional images of the body that help your doctor locate internal abnormalities.
  • CT scans. CT scans generate detailed cross-sectional images of your body that may show the location and size of your tumor and whether it has spread to other tissues or organs.
  • MRI scans. MRI scans use magnetic fields and radio waves to make 3-D images that can reveal abnormalities. Doctors also use MRI scans to determine whether your tumor has spread.
  • Positron emission tomography (PET). PET is a noninvasive technique that creates 3-D images of your organs.
  • Upper endoscopy. During upper endoscopy, a gastroenterologist or surgeon looks into your esophagus, stomach and small intestine using a thin lighted tube with a small video camera at the tip. Small samples of tissue (biopsies) may be taken if an abnormality is found. A biopsy may not identify GISTs that lie beneath the lining of the gastrointestinal tract, and other tests may be needed.
  • Endoscopic ultrasound. During this procedure, an endoscope with an ultrasound probe at the end is passed down your throat and into your stomach and, if necessary, into the upper part of your small intestine. The probe emits high-frequency sound waves that generate images of the inside of your stomach and intestine. This may help reveal a tumor not evident with upper endoscopy alone.

Your Mayo Clinic doctors also may sample and analyze tumor cells (biopsy) to confirm the diagnosis and determine the stage of your tumor. Staining your tissue sample with a special dye can show the presence of an abnormality that appears in almost all GISTs.

Mayo Clinic doctors use surgery, drugs (chemotherapy), targeted cell therapy, radiation therapy and radiofrequency ablation to treat gastrointestinal stromal tumors (GISTs).

  • Surgery. Removal of the tumor is the primary treatment for GISTs. Mayo Clinic surgeons remove small tumors through small incisions using laparoscopic surgery. If your GIST is large or attached to other organs, the surgeon may remove parts of the affected organs.

    The surgeon may also remove small amounts of tissue outside your GIST to avoid tumor rupture and prevent future obstruction to your digestive tract. You may receive chemotherapy, targeted cell therapy or radiation therapy before surgery to reduce tumor size or after surgery to destroy any remaining cancer cells.
  • Targeted therapy. Targeted therapy against an enzyme called tyrosine kinase treats your tumor by working against genetic changes that cause GISTs. Imatinib (Gleevec) is the most common of these therapies.

    If your tumor is too large or invasive to be removed with surgery, your doctor may use targeted therapy to shrink the tumor enough to make surgery possible. If your tumor is removed, your doctor may recommend targeted therapy to reduce the risk of recurrence.
  • Radiofrequency ablation (RFA). During RFA, your doctor inserts a thin needle guided by ultrasound or CT scan into your tumor and generates heat to destroy cancer cells. You may receive RFA if you have several tumors or liver tumors that can't be removed, or to relieve symptoms of GISTs such as pain.

Follow-up care

Because GISTs may recur after treatment, you'll visit your doctor every three to six months after treatment and, later, yearly. Follow-up care at Mayo Clinic includes imaging studies that allow your doctor to detect changes or tumors that may require further treatment.

Mayo Clinic works with hundreds of insurance companies and is an in-network provider for millions of people. In most cases, Mayo Clinic doesn't require a physician referral. Some insurers require referrals or may have additional requirements for certain medical care. All appointments are prioritized on the basis of medical need.

Specialists in surgery, hematology/oncology, orthopedic surgery and radiation oncology treat people who have GISTs at Mayo Clinic in Arizona.

For appointments or more information, call the Central Appointment Office at 800-446-2279 (toll-free) 8 a.m. to 5 p.m. Mountain Standard Time, Monday through Friday or complete an online appointment request form.

Specialists in surgery, hematology/oncology, orthopedic surgery (orthopedic oncology), plastic surgery, and physical medicine and rehabilitation treat people who have GISTs at Mayo Clinic in Florida.

For appointments or more information, call the Central Appointment Office at 904-953-0853 8 a.m. to 5 p.m. Eastern time, Monday through Friday or complete an online appointment request form.

Specialists in gastroenterologic and general Surgery, oncology, orthopedic oncology and radiation oncology treat people who have GISTs at Mayo Clinic in Minnesota.

The Pediatric Hematology and Oncology Division is a comprehensive center for treatment of cancer in children. The group is a member of the Children's Oncology Group (COG).

For appointments or more information, call the Central Appointment Office at 507-538-3270 7 a.m. to 6 p.m. Central time, Monday through Friday or complete an online appointment request form.

See information on patient services at the three Mayo Clinic locations, including transportation options and lodging.

Mayo Clinic researchers lead or coordinate national studies in the treatment of digestive cancers, including gastrointestinal stromal tumors. To learn more about digestive cancer research at Mayo Clinic, visit the Gastrointestinal Cancer Program.


See a list of publications by Mayo Clinic authors on gastrointestinal stromal tumors on PubMed, a service of the National Library of Medicine.

April 30, 2013