P07.07: Ultrasound features of benign asymptomatic adnexal masses submitted to surgical excision, according to IOTA terminology

Abstract

Objectives: To analyse the cases of falsely positive adnexal tumours suspected of malignancy in the application of the International Ovarian Tumour Analysis (IOTA) ADNEX, analysing the factors involved in the erroneous suspicion. Methods: Retrospective study conducted from March 2017 to March 2019 in the specific gynecological ultrasound unit of a gynecological oncology reference centre, where all cases of adnexal tumour which are suspected of malignancy were analysed. The scans were performed by the same sonographer expert, with IOTA certification. We analysed those cases considered high risk of malignancy (greater than 20%) in which the intraoperative pathological anatomy was benign, comparing them with those tumours considered low risk that were true negative, using the chi square test. Results: 274 women were included in the study period. 60% (166) who were classified as low-risk tumours: 97% (84) pathological anatomy confirmed the findings and 3 (3%) were malignant. 39% (108) were classified as high-risk tumours, which was confirmed in 68% (72) of the cases and 33 (31%) were benign. Analysing these 33 benign tumours, the average age was 60 years. When comparing false positives and true negatives, we observed an elevation of the Ca125 marker in 36% vs 7.2% (OR 7.2, p = 0.000); Regarding echogenicity, we observed 54% of solid tumours between false positives and 15% of true negatives (OR 6.6, p = 0.000), being 33% vs 1.2% in the case of solid multilocular. A Doppler score equal to or greater than 2 was found in 70% of the FP with respect to 20 of the VN (OR 8.7, p = 0.000). The most frequent resulting histological type was ovarian fibroma (39%). Conclusions: In our specific gynecological ultrasound unit, reference cancer centre, the IOTA ADNEX application presents 31% false-positive results, at the expense of the diagnosis of solid tumours, with elevation of Ca125 and vascularised tumours in postmenopausal patients. P07.05Can we improve diagnostic accuracy and ovarian salvage rates for suspected adnexal torsion? A two-year retrospective observational study