Analysis of c-kit Gene Mutation and Prognostic Factors of GISTs in the Small and the Large Bowel

ABSTRACT

PURPOSE: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors which arise anywhere in the tubular GI tract. The prognosis for GISTs that develop in the small and the large bowel is worse than it is for those that develop at other sites. We examined the significance of c-kit mutation as an independent prognostic factor for GISTs. METHODS: The hospital records of 27 patients with GISTs in the small and the large bowel who were seen from January 1991 to December 2001 at the Department of Surgery, The Catholic University School of Medicine, were reviewed. c-kit mutation was measured by using the PCR and DNA sequencing. RESULTS: Mutations in exon 11 were found in 5 cases (83.3%), exon 9 in 1 case (16.7%), and no mutations were noted in exon 13 and exon 17. All mutations in exon 11 were found in codon 560-570. c-kit mutation was observed more frequently in high-risk patients, and there was a significant difference between c-kit mutation and the survival rate (P=0.048). CONCLUSIONS: We think that codon 550~560 in exon 11 of the c-kit gene is a hotspot of mutation, but c-kit mutation is uncertain as an independent prognostic factor for GISTs.