OC154: Accuracy of transvaginal ultrasound examination for assigning a specific diagnosis to adnexal masses

To determine the diagnostic performance of subjective evaluation of ultrasound findings (pattern recognition) with regard to making a specific diagnosis in adnexal masses. Some 1066 patients in the International Ovarian Tumor Analysis study were included. They underwent transvaginal gray-scale and color Doppler ultrasound examination by an experienced examiner. Using pattern recognition each mass was classified as benign or malignant, and if possible a specific diagnosis was suggested—endometrioma, dermoid cyst, hydrosalpinx, functional cyst, paraovarian cyst, tubo-ovarian abscess, serous or mucinous cyst, adenofibroma, torsion, simple cyst, peritoneal cyst, fibroma/thecoma, rare benign tumor, borderline tumor, primary invasive cancer, metastatic cancer or rare malignant tumor. The suggested diagnosis was compared with the histological diagnosis of the surgical specimen. There were 800 benign and 266 malignant tumors. A specific diagnosis was suggested in 900 (84%) of 1066 tumors. Pattern recognition diagnosed dermoid cyst with sensitivity 86% (100/116), specificity 99% (938/950), positive likelihood ratio (LR+) 86, and negative likelihood ratio (LR−) 0.1; endometrioma with sensitivity 77% (153/199), specificity 98% (847/867), LR+ 36 and LR− 0.2; hydrosalpinx with sensitivity 86% (18/21), specificity 98% (1022/1045), LR+ 43 and LR− 0.1. Pattern recognition was associated with high LR+ (8–56) and high LR− (0.3–0.9) for all other diagnoses except peritoneal inclusion cyst (excluding rare benign tumors and simple cysts which were associated with very low LR+ and high LR−). LR+ and LR− for peritoneal inclusion cyst (n = 5) were 80 and 0.2. Using pattern recognition it is possible to make a virtually conclusive diagnosis of dermoid cyst, endometrioma and hydrosalpinx. Many other adnexal pathologies can be recognized, but not confidently excluded, using pattern recognition.