To assess the value of the International Ovarian Tumor Analysis (IOTA) simple rules, gynecology imaging reporting and data system (GI-RADS), and ovarian-adnexal reporting and data system (O-RADS) in the differential diagnosis of benign and malignant adnexal lesions.

A retrospective analysis was performed on 237 patients with adnexal tumors (unilateral/bilateral) admitted to Women and Childrens Hospital of Hubei Province from January 2018 to February 2023 (277 tumors in total), including 138 malignant tumors and 139 benign tumors, all of which were confirmed by preoperative ultrasound examination and postoperative pathology. Two senior physicians jointly performed classifications based on the IOTA simple rules, GI-RADS, and O-RADS, while another physician compared the classifications with the pathological results. The sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve (AUC) of the IOTA simple rules, GI-RADS, and O-RADS in the differential diagnosis of adnexal tumors were then calculated. The Delong test in R was used to compare the diagnostic performance of the three diagnostic methods.

The sensitivity, specificity, AUC, positive predictive value, and negative predictive value of the IOTA simple rules in the differential diagnosis of adnexal tumors were 0.993, 0.878, 0.935 (95% confidence interval [CI]: 0.902-0.969), 88.96%, and 99.19%, respectively; the corresponding values for GI-RADS classification (when the optimal cut-off value was ≥level 4) and O-RADS classification (when the optimal cut-off value was ≥level 4) were 0.870, 0.906, 0.910 (95%CI: 0.877-0.943), 77.40%, and 99.00%, and 0.964, 0.906, 0.980 (95%CI: 0.967-0.994), 91.22%, and 96.18%. The AUC between the IOTA simple rules and GI-RADS classification showed no statistically significant difference (P>0.05), while the AUC between O-RADS classification and the IOTA simple rules and GI-RADS classification differed significantly (P=0.003 and P=0.002, respectively).

In the differential diagnosis of adnexal tumors, the O-RADS classification (when the optimal cut-off value was ≥ level 4) has the highest diagnostic efficacy. The diagnostic performance of the IOTA simple rules is comparable to that of the GI-RADS classification (when the optimal cut-off value is ≥ level 4), and both have a lower diagnostic performance than the O-RADS classification.