Comparison of the value of contrast enhanced ultrasound and International Ovarian Tumor Analysis (IOTA) simple rules in the differential diagnosis of adnexal tumors

Abstract

Objective To campare the diagnostic value of contrast-enhanced ultrasound(CEUS) and International Ovarian Tumor Analysis (IOTA) simple rules in the differential diagnosis of adnexal tumors. Methods For the 101 suspicious malignant adnexal tumors discovered by conventional ultrasound, IOTA simple rules and CEUS were performed before operation. Tumors were divided into benign, uncertain and malignant according to IOTA simple rules. Tumors were scored by CEUS according to the membrane integrity, coating thickness uniformity, separation enhancement, enhance strength(no enhancement, low enhancement, equal or high enhancement), and enhanced performance(uniform and non-uniform). The ROC curve was drawn with the pathological results as the gold standard, and the best boundary value was obtained. Finally, the diagnostic efficiency of the diagnostic methods were analyzed. Results ①According to the ROC curve analysis, the area under the curve of IOTA simple rules was 0.757(P=0.000). When the uncertainty type was classified as benign, the random index was 0.41, the sensitivity was 61.54%, and the specificity was 79.59%. When the uncertainty type was classified as malignant, the random index was 0.31, the sensitivity was 96.15%, and the specificity was 34.69%. When the uncertain types were excluded the Youden index was 0.77, the sensitivity was 76.19%, and the specificity was 89.47%. ②The differences in the membrane integrity, coating thickness uniformity, separation enhancement, enhance strength, enhanced performance between benign and malignant tumors were statistically significant(P<0.01). ③According to the ROC curve analysis, the area under the curve of CEUS was 0.914(P=0.000), cut-off value was 3 score. The Youden index, sensitivity and specificity of evaluating benign and malignant adnexal tumors were 0.80, 78.85% and 91.84% respectively. ④The tumors evaluated as benign by IOTA simple rules was classified as benign. The tumors evaluated as malignant by IOTA simple rules were classified as malignant. The tumors evaluated as uncertain by IOTA simple rules and scored less than or equal to 3 points according to CEUS were classified as benign. The tumors evaluated as uncertain by IOTA simple rules and scored more than 3 points according to CEUS were classified as malignant. According to the ROC curve analysis, the area under the curve of CEUS combined with IOTA simple rules was 0.831(P=0.000). The Youden index, sensitivity and specificity in evaluating benign and malignant adnexal tumors were respectively 0.66, 86.54% and 79.59% respectively. Conclusions CEUS has a higher diagnostic efficiency than IOTA Simple Rules and the two combined in the diagnosis of adnexal tumors. Key words: Contrast-enhanced ultrasound; Neoplasms, adnexal; IOTA Simple Rules