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What is what is the marker most predominant in gastrointestinal tumor is ? and explain in detail?
Pathophysiology Tyrosine kinase receptor mutations in GIST * Over 85% of GISTs have activating KIT mutations * Commonly occur in * Exon 11(57-71%) * Exon 9 (10-18%) * Exon13 (1-4%) * Exon 17(1-4%) * One third of GISTs lacking KIT mutations have mutations in gene encoding PDGFRA, * Mutated KIT remain active in the absence of ligand binding resulting in unregulated growth and malignant transformation * Wild type GISTs are few that do not show KIT or PDGFRA mutations Surgical therapy * Complete en-block removal * Site specific * Avoidance of tumor rupture * Lymphadenectomy not advocated * Final goal: complete tumor resection with a negative margin, intact pseudocasule * Positive resection margin: Re-excision REF : BAILEY AND LOVE 27TH ED