Value of MRI-Based Ovarian-Adnexal Reporting and Data System for the Diagnosis of Adnexal Masses

Objective To assess the value of the MRI-based ovarian-adnexal reporting and data system (O-RADS MRI) for the diagnosis of adnexal masses. Methods A total of 407 patients who underwent dynamic contrast enhancement (DCE)-MRI and pathological examination (gold standard) at the Department of Radiology,Central Hospital of Wuhan between May 2017 and December 2022 were enrolled in this study.Two radiologists performed the O-RADS MRI scoring of adnexal masses according to MRI features and calculated the malignancy rate of adnexal masses by O-RADS MRI score,enhancement type,and mass type.Moreover,receiver operating characteristic curves were established to further evaluate the diagnostic values of O-RADS MRI score,enhancement type,and mass type for adnexal masses. Results A total of 502 adnexal masses were identified in the 407 patients enrolled in this study,including 364 benign masses and 138 malignant masses (including junctional masses).Radiologist 1 reported the malignancy rates of 0,0,5.4%,80.0%,and 89.7% and radiologist 2 reported the malignancy rates of 0,0,5.8%,86.2%,and 83.0% for the adnexal masses with the O-RADS MRI scores of 1-5,respectively.With O-RADS MRI ≥4 indicating malignant masses,the sensitivity,specificity,accuracy,positive predictive value,negative predictive value,false negative rate,and false positive rate were 94.2%,93.6%,93.8%,84.9%,97.7%,2.3%,and 15.1% for radiologist 1 and 93.4%,93.6%,93.6%,85.4%,97.4%,3.6%,and 14.6% for radiologist 2,respectively.The malignancy rates of the adnexal masses presenting no enhancement,cystic wall enhancement,type Ⅰ curve,type Ⅱ curve,and type Ⅲ curve were 0,1.3%,5.7%,81.2%,and 89.0% as reported by radiologist 1 and 0,1.2%,11.3%,87.6%,and 80.0% as reported by radiologist 2,respectively.The malignancy rates of the adnexal masses that were cystic lesions,cystic segregated lesions,solid lesions,cystic solid lesions,and cystic solid segregated lesions were 0,7.1%,38.7%,79.1%,and 89.8% as reported by radiologist 1 and 0,8.1%,37.8%,72.4%,and 89.6% as reported by radiologist 2,respectively.With type Ⅱ and type Ⅲ curves as the criteria for malignancy,the sensitivity of radiologists 1 and 2 was lower for cystic segregated lesions,both at 50.0%.For the masses containing solid components,radiologists 1 and 2 demonstrated low specificity,which was 57.7% and 56.5%,respectively.False-positive masses contained solid components and were mostly fibroadenomas or adnexal leiomyomas,while false-negative masses were mostly junctional cystadenomas with no or few solid components. Conclusions The O-RADS MRI risk stratification has a high diagnostic value for adnexal masses.Further evaluation and refinement are needed to reduce the false-positive rate.