The accuracy of preoperative serum CA-125 levels to predict lymph node metastasis in a population of South African women with endometrial carcinoma

Background: The purpose of the study was to evaluate the predictive value of serum CA-125 levels in the preoperative assessment of endometrial carcinoma in a setting where late presentation is common. Method: This retrospective study evaluated women with pathologically proven endometrial carcinoma scheduled for surgery between January 2012 and January 2017, who had preoperative serum CA-125 test results. The association of CA-125 with a variety of histological factors was evaluated using Spearman’s correlation and receiver operator characteristic (ROC) curves to evaluate sensitivity and specificity. Results: Fifty-eight patients were included in the study, 34 (58.6%) of whom were FIGO stage II–IV. Elevated CA-125 levels were significantly correlated with late FIGO stage (p < 0.001), myometrial invasion (p < 0.001) and lymph node metastases (p < 0.001). The most appropriate cut-off point of CA-125, where an increase in sensitivity was not associated with a fall-off in specificity, was 20 IU/ml, reaching a sensitivity of 90% and a specificity of 67% for detection of lymph node metastases. Conclusion: Among this group of women with endometrial cancer, the preoperative serum CA-125 level was associated with lymph node metastases and we found a CA-125 of 20 IU/ml or more to be predictive. These findings suggest that, among similar populations, CA-125 could be done preoperatively and could be used to determine the need for node dissection. Since our findings are from a small retrospective cohort, this should be validated in a prospective study on early stage disease.