GIST and gastrointestinal leiomyosarcoma exhibit a range of biologic behavior, but distinction between these tumors is clinically important in people as activating mutations in exon 11 of the c-kit gene are implicated in the pathogenesis of many GIST and contribute to remarkable sensitivity of these tumors to tyrosine kinase inhibitors (103). Here, KIT is linked to gastrointestinal stromal tumor.