Abstract
OBJECTIVES: To compare the diagnostic performance of contrast-enhanced magnetic resonance imaging (CE-MRI) and computed tomography (CT) in evaluating treatment response for recurrent endometrial cancer (EC), and to assess the added value of integrating imaging findings with biomarker data. METHODS: This retrospective case-control study included 217 patients with recurrent EC treated between January 2020 and December 2023. Patients were divided into response (n = 102) and non-response (n = 115) based on Response Evaluation Criteria in Solid Tumors (RECIST) (1.1). An internal validation cohort (n = 142) and an external cohort (n = 168) were also analyzed. Preoperative CE-MRI and CT scans were reviewed by experienced radiologists. Biomarker positivity rates - including estrogen receptor (ER), progesterone receptor (PR), cancer antigen 125 (CA125), cancer antigen 19-9 (CA19-9), carcinoembryonic antigen (CEA), and ovarian cancer-related protein 1 (OVX1), were assessed. Multivariate logistic regression and receiver operating characteristic (ROC) analyses were performed to evaluate diagnostic performance, and an integrated model combining imaging and biomarkers was developed. RESULTS: CE-MRI achieved an AUC of 0.864, sensitivity of 78.3%, and specificity of 86.3%, while CT showed an AUC of 0.854, sensitivity of 81.2%, and specificity of 83.4%. The integrated model improved performance with an AUC of 0.889, sensitivity of 94.3%, and specificity of 81.2%. Internal and external validation models yielded AUCs of 0.859 and 0.918, respectively. CONCLUSIONS: Both CE-MRI and CT are effective in assessing treatment response, with CE-MRI offering slightly superior specificity. Integration of imaging and biomarker data significantly enhances diagnostic accuracy, supporting its potential in optimizing individualized treatment strategies for recurrent EC.