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What is All are true about GIST EXCEPT? and explain in detail?
Ref: Robbins Pathology, 9th ed. pg. 775-76* Majority of gastrointestinal stromal tumors originate from stomach. The cell of origin is interstitial cell of Cajal which are present in muscularispropria.* The useful marker is c-kit (CD 117) detectable in 95% of patients.* PET scan is the imaging modality of choice* Treatment is tyrosine kinase inhibitors like imatinib mesylate.