Performance of grayscale combined with contrast-enhanced ultrasound in differentiating benign and malignant pediatric ovarian masses

Objectives To evaluate grayscale US combined with contrast-enhanced ultrasound (CEUS) in the preoperative differentiation between benign and malignant ovarian masses in a pediatric population. Materials and methods This retrospective study enrolled patients who underwent grayscale US and CEUS before surgery because of ovarian masses between July 2018 and September 2023, with available histopathologic or follow-up results. Two senior radiologists summarized the grayscale US and CEUS characteristics of all ovarian masses, including percentage of solidity, ascites, vascularity, and enhanced vessel morphology. These characteristics were then independently reviewed by radiologists with different experience to assess interobserver agreement. Diagnostic performance was evaluated using the area under the receiver operating characteristic curve (AUC), while interobserver agreement was evaluated by intraclass correlation coefficient (ICC). Results A total of 26 children (median age: 10.1 [7.5, 11.7] years; age range: 0-14 years; benign: 15 patients) were included. The main characteristics of malignant ovarian tumors were abundant blood flow and twisted blood vessels within the mass, enhanced portion of the mass over 50 percent (all p < 0.001). The grayscale US combined with CEUS showed better diagnostic performance than the grayscale US alone (AUC = 0.99 [95% CI: 0.95, 1.00] vs AUC = 0.70 [95% CI: 0.50, 0.90] p < 0.001). A statistically significant AUC before and after CEUS was also shown between two junior radiologists (0.75 vs 0.92 and 0.69 vs 0.86, respectively, both p < 0.05). ICC of CEUS was better than that of grayscale US among radiologists. Conclusion The combination of grayscale US and CEUS might improve the diagnostic accuracy in differentiating benign and malignant pediatric ovarian masses.