Most gastrointestinal stromal tumors (GISTs) develop within the wall of the stomach or small intestine. These tumors often grow into the empty space inside the gastrointestinal (GI) tract, so they might not cause symptoms right away unless they are in a certain location or reach a certain size.
Small tumors might not cause any symptoms and can be found accidentally when the doctor is checking out some other problem. These small tumors often grow slowly.
GISTs tend to be fragile tumors that can bleed easily. In fact, they are often found because they cause bleeding into the GI tract. Signs and symptoms of this bleeding depend on how fast it occurs and where the tumor is located.
Bleeding from the GI tract can be very serious. If you have any of these signs or symptoms, see a doctor right away.
Other symptoms of GISTs can include:
Some tumors grow large enough to block the passage of food through the stomach or intestine. This is called an obstruction, and it can cause severe abdominal pain and vomiting.
Because GISTs are often fragile, they can sometimes rupture, which can lead to a hole (perforation) in the wall of the GI tract. This can also result in severe abdominal pain. Emergency surgery might be needed in these situations.
Although many of the possible symptoms of GISTs (like belly pain and nausea) can be caused by things other than cancer, if you have these symptoms, especially if they last for more than a few days, it's important to see a doctor.
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Casali PG, Dei Tos AP, Gronchi A. Chapter 60: Gastrointestinal Stromal Tumor. In: DeVita VT, Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology. 11th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2019.
Morgan J, Raut CP, Duensing A, Keedy VL. Epidemiology, classification, clinical presentation, prognostic features, and diagnostic work-up of gastrointestinal stromal tumors (GIST). UpToDate. 2019. Accessed at https://www.uptodate.com/contents/epidemiology-classification-clinical-presentation-prognostic-features-and-diagnostic-work-up-of-gastrointestinal-stromal-tumors-gist on October 14, 2019.
National Cancer Institute. Physician Data Query (PDQ). Gastrointestinal Stromal Tumors Treatment. 2018. Accessed at www.cancer.gov/types/soft-tissue-sarcoma/hp/gist-treatment-pdq on October 14, 2019.
Last Revised: December 1, 2019
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