The prognosis of GIST depends on tumor size, mitotic activity, anatomic location, and completeness of surgical resection. Tumors smaller than 2 cm with a low mitotic count and gastric location have a very good prognosis, while larger and more aggressive tumors, particularly extragastric, have a higher risk of recurrence or metastases.
Targeted therapy with imatinib has significantly improved survival in patients with metastatic or recurrent disease. 5-year survival rates range from >90% for low-risk patients to <50% for untreated or high-risk untreated cases.
Long-term follow-up is required, as recurrences may occur even after several years.
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