Serum CA-125 as a predictor in the early diagnosis of ectopic pregnancy in Vietnam - A case-control study

Introduction: This study aimed to determine the predictive value of cancer antigen-125 (CA-125) in combination with serum beta-human chorionic gonadotropin (β-hCG) and progesterone in the early detection of ectopic pregnancy (EP).

Methods: Between May 2019 and May 2020, the cross-sectional study recruited 42 cases of EP and 42 cases of IUP at the same gestational age who visited the Department of Obstetrics and Gynecology, Hospital of Hue University of Medicine and Pharmacy. EP was diagnosed based on surgical (laparoscopy) and postoperative pathology examination.

Results: There were significant differences of mean level of β-hCG (2570 mUI/mL vs. 18357.7 mUI/mL), progesterone (10.79 ± 8.16 ng/ml vs. 27.42 ± 4.17 ng/ml) and CA-125 (26.90 ± 10.26 U/mL vs. 70.61 ± 20.89 U/mL) between the EP and the IUP groups (p < 0.001). In the prediction of early diagnosis of EP, the cut-off value of CA-125 at 30.94 U/mL has a sensitivity of 89.3% and a specificity of 87,9%; the cut-off value of β hCG at 2750mIU/ml has the sensitivity of 75%, specificity of 78,8%; the cut-off value of progesterone at 10.24 ng/mL has the sensitivity of 85.7%, specificity of 81.8%. A combination of CA-125, β hCG, and progesterone had a sensitivity of 92.8% and a specificity of 90.9% in early diagnosis of EP.

Discussion: Serum CA-125 levels can be used independently or in combination with other markers in the early diagnosis of EP.