Background: To investigate the relationship between preoperative serum CA 125 levels and para-aortic lymph node (PAN) metastasis as determined by systematic pelvic and para-aortic lymph node dissection in endometrial carcinoma.
Methods: This study included 180 patients (n = 55, premenopausal; n = 125, postmenopausal) with endometrial carcinoma treated by complete surgical staging. Cut-off values of preoperative serum CA 125 levels for PAN metastasis were determined by receiver characteristic curve (ROC) analysis. Logistic regression analysis was used to determine independent predictors for PAN metastasis.
Results: The median serum CA 125 levels of patients with PAN metastasis were significantly higher than the levels of those with no metastasis in both premenopausal and postmenopausal groups. Based on ROC analysis, we could determine four cut-off values (70 and 210 U/mL for premenopausal patients, 20 and 60 U/mL for postmenopausal patients) and categorize the serum CA 125 levels into low, moderate and high groups. By logistic regression analysis, the CA 125 level and nuclear grade were found to be significant predictors of PAN metastasis, respectively. Using this model, the patients were stratified into three risk groups. The probabilities of PAN metastasis for patients in the low-risk, intermediate-risk and high-risk groups were less than 2%, 2-25% and more than 50%, respectively.
Conclusions: Serum CA 125 levels and nuclear grade are important risk factors for PAN metastasis in endometrial carcinoma.