Assessment of Different Neoplasias in the Adnexa Model Versus Risk of Malignancy Index as a Tool for Predicting Ovarian Malignancy in Postmenopausal Ovarian Cysts

Abstract Background Ovarian cancer is the most lethal gynecologic malignancy and every attempt should be made to develop screening programs to detect it at its early stages in order to improve survival rate. Using the ADNEX model in screening for ovarian cancer will help in triaging patients with adnexal masses before undergoing surgery which will help in optimizing outcomes particularly for those with ovarian malignancy. Patients & methods: This was a prospective study which included fifty postmenopausal patients with adnexal mass. All the included patients underwent ultrasound assessment of the adnexal mass and measurement of CA 125 level. Then, the data were collected to calculate the RMI, and integrated to IOTA ADNEX calculator. The primary outcome was determining the predictive accuracy of both RMI and ADNEX model for differentiating between benign and malignant ovarian tumors by setting both against the gold standard histopathology Results Out of the included 50 patients, 56% had benign ovarian lesions, 12% had borderline ovarian tumors, and 24% had malignant ovarian tumors. The Area under the receiver operating characteristic curve (AUC) for the RMI was 0.799 and with cutoff value of 115, the sensitivity was 81.8%, the specificity was 60.7% while the AUC was 0.864 for the ADNEX model and at 10% cutoff, the sensitivity was 91.1% and the specificity was 65%. Performance of the ADNEX for the five tumor types was highest when benign histopathology was compared as stage Ⅱ - Ⅳ malignant cases with AUC of 0.823. Conclusion ADNEX model is more sensitive than RMI for differentiating between benign and malignant tumors and it can be used as screening test. However, the application of ADNEX model needs significant experience in ultrasound evaluation of adnexal masses before it can be an integral part in the screening pathway of ovarian malignancy in postmenopausal patients with adnexal masses. Clinicaltrials.gov ID: NCT05755841 – Data of registration: 3/30/2024 “retrospectively registered”