Gastrointestinal stromal tumors (GISTs) are a type of tumor that occurs in the digestive system. The digestive system includes the esophagus, liver, stomach, gall bladder, large and small intestines, and rectum. The digestive system processes food to fuel the body and gets rid of waste. About half of GISTs occur in the stomach, but they can occur anywhere in the digestive system.
GISTs are rare. All GISTs are now considered potentially cancerous.
The cause of GISTs is not well understood.
Many people with GIST have a defect in a gene called c-kit. Usually, this gene is not active. However, in people with GIST, the c-kit gene often has a defect and is active, which enables the cells to grow and divide uncontrollably. This may explain why a GIST forms.
Theories about GISTs say that they begin in special cells of the digestive system. These cells are called interstitial cells of Cajal (ICCs). They send signals that tell the digestive system to contract, which moves food and liquid through the digestive system.
GIST is most common in people over age 50. It is rare in children. Risk factors for GIST are mostly unknown. Possible risk factors include:
- Neurofibromatosis—a genetic disorder of the nervous system
- Family history of GIST—rare
GISTs may not cause any symptoms until they grow to a certain size. Symptoms may include:
- Tiredness and weakness
- Fever; sweating at night
- Weight loss
- Feeling full after eating a small amount of food
- Abdominal pain
- Painless lump in the abdomen
- Nausea and/or vomiting
- Blood in stool or vomit
- Problems swallowing
Your doctor will ask about your symptoms and medical history. A physical exam will also be done.
Your bodily structures will need to be viewed to determine the location and size of the tumor. This can be done with:
- Barium swallow
- Barium enema
- Computed tomography (CT) scan
- Magnetic resonance imaging (MRI) scan
- Positron emission tomography (PET) scan
Your bodily tissues may be tested. This can be done with a fine-needle biopsy.
Talk with your doctor about the best treatment plan for you. Treatment options include:
Surgery is used to treat a GIST that has not spread. Surgery to treat GIST should be done by an experienced cancer surgeon. GISTs are delicate tumors. There may be an increased risk of cancer spreading if the sac surrounding the GIST is opened during surgery.
You may be given medications to shrink the tumor before surgery. For small tumors, laparoscopic surgery may be used.
Even if the tumor is large or growing into other organs, your doctor may use surgery to remove some or the entire tumor. This reduces the chance that the tumor will grow large enough to block the digestive system.
You may be given a medication called a tyrosine kinase inhibitor. It may make the tumor shrink or stop growing.
- Reviewer: Michael Woods, MD
- Review Date: 06/2014 -
- Update Date: 05/11/2013 -