ABSTRACT
Objective To investigate the status and significance of KIT,PDGFRA and DOG1 gene mutation in gastrointestinal stromal tumors (GIST).Methods 100 GIST patients treated in the First Affiliated Hospital of Guangxi Medical University between May 2002 and May 2013 were analyzed restrospectively.DNA was isolated and amplified for the all exons of KIT,PDGFRA and DOG1.Each PCR product was sequenced to find the position and type of mutation.Results KIT mutations were identified in 75 cases (75％).PDGFRA mutations were found in 16 cases (16％).No DOG1 mutations were found.The overall 5-year survival was 58.8％.Log-rank univariate survival analysis showed that the primary location,tumor size,metastasis,operational mode,type of tumor cells,invasion of the smrounding organs,invasion of the smooth muscle,mitotic counts of the tumor cells,deletions in exon 11 KIT and targeting therapy were significant prognostic factors (all P ＜ 0.05).COX regression model showed that tumor size,metastasis,operational method,invasion of the surrounding organs,mitotic counts of the tumor cehs,deletions in exon 11 KIT and targeting therapy were related to prognosis.Conclusion KIT and PDGFRA mutations are mutually exclusive.The overexpression mechanism of DOG1 is not related to DOG1 gene mutation.The related gene mutations affect the prognosis of GIST.