gastrointestinal stromal tumor
Pronunciation: gas-troh-in-TES-tin-al STROH-mal TOO-mer
A type of soft tissue sarcoma arising from interstitial cells of Cajal in the gastrointestinal tract wall.
Full Definition
Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract, arising from the interstitial cells of Cajal or their precursors. These tumors are characterized by mutations in KIT or PDGFRA genes in approximately 85% of cases, leading to constitutive activation of receptor tyrosine kinases. GISTs most commonly occur in the stomach (60%) and small intestine (30%), with symptoms varying from asymptomatic incidental findings to gastrointestinal bleeding, abdominal pain, or obstruction. Diagnosis requires immunohistochemical confirmation of KIT (CD117) or DOG1 positivity. Treatment involves surgical resection when feasible, with targeted therapy using tyrosine kinase inhibitors like imatinib for advanced or high-risk disease.
Usage
Usage note: Spell out fully or abbreviate as GIST. Hyphenate the adjective form: 'gastrointestinal-stromal.'
In Context
- "Immunohistochemistry confirmed CD117 positivity, establishing the diagnosis of gastrointestinal stromal tumor." — Pathology report
- "The 8-cm gastric gastrointestinal stromal tumor showed high mitotic rate, indicating intermediate risk for recurrence." — Multidisciplinary oncology meeting