OC120: Contrast-enhanced sonography in the discrimination of benign and malignant adnexal masses

To investigate the potential usefulness of contrast-enhanced power Doppler sonography with real-time imaging technique in the differentiation of benign and malignant adnexal lesions. Before surgical treatment, 101 adnexal masses were prospectively evaluated with power Doppler sonography before and after injection of Levovist. Initially, vascular index of the tumour was estimated with a colour quantifying software. Real-time post-injection sequences were computerized by a time-intensity analysis software to obtain an enhancement curve. Several parameters were chosen to study kinetic properties of the contrast agent during the uptake and wash-out times. Thus, time between injection and enhancement beginning, uptake or wash-in time, wash-out half-time, wash-out time and area under the enhancement curve were compared between benign and malignant tumours. First of all, the reproducibility of these criteria was tested with 15 of those 101 procedures. There were 23 cases of ovarian malignancies and 78 benign adnexal lesions. Our procedure was well reproducible with an average kappa index of 0.92. Vascular index was considerably higher in malignant tumours. About contrast enhancement, uptake time parameters were not characteristic for any tumours. However, wash-out times and areas under curves were significantly more important in ovarian malignancies than in other tumours. Finally, we determined threshold values with Roc curves analysis to obtain good diagnostic efficiencies for this new procedure: sensitivity between 96 and 100%, specificity between 83 and 98% according to different parameters. Sonographic estimation of tumoral vascular index and enhanced power Doppler imaging may easily and precisely discriminate benign from malignant adnexal lesions. However, multivariate analysis must be carried out to determine place and benefits of this new procedure among usual diagnostic strategies.