Introduction/Background To compare GI-RADS and O-RADS reporting systems for managing adnexal masses.

Methodology Single center prospective study comprising a non-consecutive series of women diagnosing as having an adnexal mass evaluated and treated at our institution between January 2019 and December 2020. All women underwent transvaginal/transabdominal ultrasound examination. Pregnant women and girls under 18 years were not included. Adnexal masses were classified using GI-RADS system (based on subjective impression of the examiner). Management (follow-up, surgery by general gynecologist, MRI as second step technique or referral to Gynecologic oncologist) was based on this system. Additionally, O-RADS classification based on ADNEX model malignancy risk estimation (not using CA-125) was estimated. Diagnostic performance of both systems (considering GI-RADS or O-RADS 4 and 5 as malignant) were assessed and compared. Reference standard was or follow-up (masses with > 12 months and no signs of malignancy were considered as benign)

Results One hundred and ninety-eight women (240 masses) were included in the study. GI-RADS classifications of the masses were as follows: GI-RADS-2: 20, GI-RADS 3: 178, GI-RADS-4: 25 and GI-RADS- 5: 17. According to O-RADS, masses had been classified as follows: O-RADS-2: 28, O-RADS 3: 173, O- RADS-4: 25 and O-RADS-5: 14. 136 masses were managed conservatively and 104 were removed surgically. No mass on follow-up turned to be an ovarian cancer. Reference standard was benign in 217 masses and malignant in 23 masses. Diagnostic performance of both systems is shown in table.

Conclusion GI-RADS or O-RADS systems perform similarly for managing adnexal masses