Preoperative prediction of the histological features and lymph nodes status of borderline ovarian tumors: The role of conventional ultrasound and contrast-enhanced ultrasound

BackgroundBorderline ovarian tumors (BOTs) represent a rare group of neoplasms exhibiting abnormal epithelial proliferation with cellular atypia while lacking stromal invasion or infiltrative destructive growth. And postoperative recurrence may be associated with histological features and lymph node status. Therefore, preoperative prediction of BOTs' histological characteristics and lymph node status is of paramount importance for formulating surgical plans and follow-up treatments.ObjectiveTo investigate the value of conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS) characteristics for preoperative identification of histological features and lymph node status in BOTs.MethodsPatients with pathologically confirmed primary BOTs were enrolled, which classified into high-risk and low-risk groups based on whether the presence of at least one of microinvasion, micropapillary pattern, extraovarian implantation, or lymph node invasion. CEUS was performed at the maximal solid tumor component identified on gray-scale imaging, with bolus injection of contrast agent and dynamic recording of the wash-in to wash-out phases for quantitative contrast kinetics analysis. A comparative analysis of US and CEUS characteristics was conducted between the groups, with subsequent longitudinal assessment of recurrence-free survival (RFS) curves employing Kaplan-Meier methodology.ResultsThe study comprised 58 patients with BOTs, stratified into low-risk (n = 37) and high-risk (n = 21) groups, with mean patient ages of 42.8 ± 11.8 years. No statistically significant differences were observed in tumor size (maximum diameter, <i>p</i> = 0.840) or location (unilateral versus bilateral, <i>p</i> = 0.077) between the two groups on US. The type of tumor, proportion of solid components, and color score were observed to statistically significantly differ between the two groups (all <i>p</i> < 0.05). Iso- or hyper-enhancement, early or synchronously wash-in, and early wash-out were more likely to occur in the high-risk group (16/21, 76.2%; 11/21, 52.4%; 11/21, 52.4%) than in the low-risk group (15/37, 40.5%; 5/37, 13.5%; 9/37, 24.3%). In quantitative parameters, there were significant differences in MeanLin, PE, RT, TTP, WiR, WiPI, WoAUC, WiWoAUC, FT, and WoR between the two groups (all <i>p</i> < 0.05). During the follow-up, there were 3 cases recurrence in the high-risk group, while no recurrence was observed in the low-risk group.ConclusionThe combination of US and CEUS is capable of facilitating preoperative prediction of the histological features and lymph node status of BOTs, and holds potential value for identifying the recurrence risk.