Question 14#
The standard treatment for an isolated 3 cm gastrointestinal stromal tumor (GIST) in the body of the stomach is:
A. ImatinibB. Endoscopic ablation
C. Wedge resection
D. Subtotal gastrectomy
Correct Answer is C
Comment:
Gastrointestinal stromal tumors (GISTs) are submucosal tumors that are slow growing, and arise from interstitial cells of Cajal (ICC). Prognosis in patients with GISTs depends mostly on tumor size and mitotic count, and metastasis, when it occurs, is typically by the hematogenous route. Any lesion >1 cm can behave in a malignant fashion and may recur. Thus, all GISTs are best resected along with a margin of normal tissue-wedge resection with clear margins is adequate surgical treatment. True invasion of adjacent structures by the primary tumor is evidence of malignancy. If safe, en bloc resection of involved surrounding organs is appropriate to remove all tumor when the primary is large and invasive. Five-year survival following resection for GIST is about 50%. Most patients with low-grade lesions are cured (80% 5-year survival), but most patients with high-grade lesions are not (30% 5-year survival). Imatinib, a chemotherapeutic agent that blocks the activity of the tyrosine kinase product of c-kit, yields excellent results in many patients with metastatic or unresectable GIST, and is also recommended in high risk groups as an adjuvant therapy.
Algorithm for treatment of patients with gastrointestinal stromal tumor (GIST):
