ObjectiveTo explore the application value of gynaecological imaging report and data system（GI-RADS）in the differential diagnosis of benign and malignant adnexal tumors.MethodsA total of 180 patients with adnexal tumors who confirmed by operation and pathology in our hospital were analyzed retrospectively.There were 39 cases of malignant adnexal tumors and 141 cases of benign adnexal tumors.They were classified by GI-RADS according to the ultrasonic characteristics of adnexal tumors.The diagnostic efficacy and cut-off value of ultrasound were calculated based on the gold standard of pathological results by receiver operating characteristic（ROC）curve.ResultsAmong 180 cases of adnexal tumors

15 cases were judged as GI-RADS 2 and none was malignant.There were 112 cases of GI-RADS 3 and 1 case of which was malignant.There were 25 cases of GI-RADS 4 and 12 cases of which were malignant.There were 28 cases of GI-RADS 5 and 26 cases of which were malignant. The sensitivity

specificity

positive predictive value

negative predictive value and accuracy of GI-RADS 5 in predicting malignant tumors were 66.7%

98.6%

92.9%

91.4% and 91.7%

the area under the ROC curve（AUC）was 0.826.And these parameters of GI-RADS 4 and 5 in predicting malignant tumors were 97.4%

89.4%

71.7%

99.2% and 91.1%

AUC was 0.934

respectively.There were significant differences in sensitivity

specificity

positive predictive value

negative predictive value and AUC between the two methods（all P<0.05）.ConclusionGI-RADS classification can be used to differentiate benign and malignant adnexal tumors with excellent diagnostic efficiency

and tumors with GI-RADS classification > 3 has high malignant risk.