CRITICAL-EVALUATION OF THE SPECIFICITY OF MRI AND TVUS FOR DIFFERENTIATION OF MALIGNANT FROM BENIGN ADNEXAL LESIONS

The aim of our work was to study the specificity of MRI in comparison with transvaginal US for differentiation of malignant from benign adne xal lesions. A total of 67 patients with clinically suspicious adnexal lesions were evaluated by MRI. Transaxial and coronal images were acq uired using T1-weighted sequences before and following IV contrast and T2-weighted sequences. In all patients transvaginal ultrasound examin ations (TVUS) were performed. For both imaging modalities each lesion was classified separately as either benign or malignant according to p reviously published criteria. Pathologic findings were available in 65 cases. Both MRI and TVUS correctly classified the 12 malignant lesion s (sensitivity 100%). Specificity (MRI: 78.2%, TVUS: 65.5%) and accura cy (MRI: 82%, TVUS: 71.6%) were higher with MRI than with TVUS, but di fferences were statistically not significant (p = 0.18 and p = 0.20, c hi-square test). There was agreement/disagreement between findings of MRI and US in 52/15 lesions. The macroscopic criteria for malignancy a re unspecific and result in a limitation of the specificity of both MR I and TVUS. The MRI technique is a valuable adjunct to TVUS by enablin g further clarification of adnexal tumors with equivocal complex or so lid vaginal sonographic findings.