Objective To evaluate the efficacy of endoscopic ultrasonography in diagnosis of gastric stromal tumor and the efficacy and safety of the application of endoscopic

submucosal excavation in the treatment of gastric stromal tumor. Methods Thirty patients with gastric stromal tumor was diagnosed by endoscopic ultrasonography which confirmed origin,size,location,blood supply of the lesions,then treated by endoscopic submucosal excavation,evaluating the efficacy and safety.The results were compared with the postoperative findings.The Kappa evaluation criterion was used to analyze the consistency.Results Endoscopic ultrasonography showed gastric stromal tumors were predominantly located in the bottom and body of  stomach.The diameters were between 0.4 and 5.5centimeters.Twentytwo lesions whose diameter less than 3cm appeared spherical or hemispherical uplift,showing homogeneous hypoechoic or intermediate internal echo under endoscopic ultrasonography.The diameters of eight lesions were more than 3cm longer.Twenty-nine tumors were completely removed by endoscopic submucosal excavation and one tumor was partly removed.Three patients were perforated during the operation,then cured by conservative therapy.Mild bleeding occurred in all cases,then managed by argon plasma coagulation or hot biopsy.Twentyseven cases were consistent in the invasion risk classificational of gastric stromal tumor under endoscopic ultrasonography and pathologic classification.The Kappa evaluation criterion was used to analyze the consistency. ConclusionsThe invasion risk classification of gastric stromal tumor under endoscopic ultrasonography has good consistency with pathologic classification.Endoscopic submucosal excavation is safe and effective,and the use of endoscopic ultrasonography for evaluating lesions before treatment is very important.