EP23.21: Diagnostic accuracy of modified benign descriptor two in the diagnosis of teratomas

To evaluate the diagnostic accuracy of the modified benign descriptor two in the diagnosis of teratomas. Ambispective observational study based on ultrasound data collected at a University Hospital with a gynecologic oncology unit between 2012 and 2023. Two IOTA-certified level III gynecologists classified adnexal masses using the MBD. The main result was the correct classification of teratomas, based on the second descriptor of the MBD (MBD 2). Histopathology was used as the diagnostic reference standard. A diagnostic accuracy study was performed. A total of 1,047 adnexal masses were assessed, of which 656 (62.6%) were included when they met the classification criteria for their evaluation based on MBD. 72 masses were diagnosed as teratomas by the MBD 2, of which 65 (90.3%) corresponded to teratomas by histopathology. 9.7% (7/72) were false negatives, and the diagnoses that caused confusion were: endometrioma (28.6%), hemorrhagic corpus luteum (28.6%), follicle cyst (14.2%), serous cystadenoma (14.2%), and serous cystadenoma with local proliferation (14.2%). The diagnostic yield for MBD 2 had a sensitivity of 92.86%, specificity of 98.81%, positive predictive value of 90.28%, negative predictive value of 99.14%, and diagnostic accuracy of 98.17%. In our experience, MBD 2 has the ability to appropriately classify most teratomas, with a diagnostic accuracy of 98%, which is why it could be a valuable tool in clinical practice when assessing teratomas.