The Node Reporting and Data System (Node-RADS) for standardized MRI evaluation of lymph nodes in endometrial cancer, integrated with clinicopathological and molecular data

Objectives: To evaluate the diagnostic performance of Node-RADS score using magnetic resonance imaging (MRI) in predicting lymph node involvement (LNI) in patients with endometrial cancer (EC). Additionally, the applicability of the Node-RADS score was evaluated by three readers with different levels of experience in pelvic imaging. Finally, this study investigated the correlation between the Node-RADS score and the extent of myometrial invasion, histological type, lympho vascular invasion (LVI) and molecular subtype. Methods: Out of 108 cases, 82 patients with histologically confirmed locally advanced EC met the inclusion criteria for retrospective analysis. LNI risk was assessed for each pelvic lymph node station using a Node-RADS score (1-5). Diagnostic accuracy was determined by comparing scores to histologic findings, considered as the gold standard. Three independent readers with different experience levels assigned scores. Results: The Node-RADS score strongly correlated with histologically confirmed LNI (AUC: 0.832). A cutoff of Node-RADS >= 3 optimally detected metastatic lymph nodes, with 85.71 % sensitivity and 76.47 % specificity. Interobserver agreement was high, with kappa values of 0.86 (senior vs. junior reader 1) and 0.70 (senior vs. junior reader 2). A significant positive correlation was found between Node-RADS score and myometrial invasion as well as LVI. Conclusion: Node-RADS score is a reliable, standardized tool for assessing LN stations and enhancing diagnostic accuracy in locoregional staging of EC.