Gastrointestinal Stromal Tumors
Gastrointestinal stromal tumors (GIST) begin in the interstitial cells of Cajal (ICCs), which are located in the wall of the gastrointestinal tract. ICCs help with the muscle contraction that moves food and liquid along the digestive tract.
Gastrointestinal Stromal Tumor Causes
As with many types of cancer, what causes gastrointestinal stromal tumors isn’t known. Lifestyle changes and environmental risk factors don’t appear to play a role in the development of GISTs, however, changes in genes (made up of DNA) may cause the condition. Gene mutations related to GISTs can be passed down from a parent to a child, but many gene changes appear to occur for no reason.
In many cases of gastrointestinal stromal tumors, either one of the following gene mutations are present:
- A mutation in the KIT oncogene – The KIT oncogene produces the CD117 protein which directs cells to grow and divide. In 95% of people with GIST, the KIT gene is mutated and is active in ICCs, resulting in an overproduction of cells.
- A mutation in the PDGFRA gene – Similar to KIT mutations, changes in the PDGFRA gene in ICCs cause an excess of PDGFRA protein to be made. An overproduction of growing and dividing cells is the result.
Gastrointestinal Stromal Tumor Symptoms
Many patients don’t experience symptoms with gastrointestinal stromal tumors. But others may experience:
- Bloating or abdominal pain
- Bleeding from the bowel
- Decreased appetite
Diagnosing Gastrointestinal Stromal Tumors
Diagnosing GISTs typically involves:
- A physical examination
- Blood work
- An upper endoscopy and biopsy
- Computed tomography (CT) scan
- Positron emission tomography (PET) scan
Gastrointestinal Stromal Tumor Treatments
Gastrointestinal stromal tumors are typically treated with:
- Surgery to remove localized, low-risk GISTs
- A medication called imatinib
At Tampa General Hospital’s Cancer Institute, our expert gastrointestinal oncologists will tailor a treatment plan based on each patient’s needs and the severity of their condition.