ObjectiveTo compare accuracy of serum human epididymis protein 4 (HE4) levels with cancer antigen 125 (CA-125) levels as biomarkers for ovarian cancer.MethodsThe study population included 94 Korean women, including 32 patients with a diagnosis of ovarian cancer and 62 patients with a diagnosis of benign ovarian tumor. All diagnoses were confirmed by histopathological analysis. Serum HE4 levels were assessed using an HE4 enzyme immunoassay, which were performed according to the manufacturer's instructions. Serum CA-125 levels were determined using a Modular analytics E170 module.ResultsThe median serum CA-125 and HE4 levels were significantly higher in patients with ovarian cancer than those with other benign tumors (CA-125, 394.1 U/mL vs. 22.7 U/mL; HE4, 56.7 pM vs. 18.5 pM; P < 0.05 in both). An additional comparison revealed that the patients with endometriosis had greater median serum CA-125 levels than those with other benign ovarian tumors (32.0 U/mL vs. 17.9 U/mL, P = 0.03). Conversely, the median serum HE4 levels were similar among the two benign ovarian tumor groups, with no statistically significant difference observed (19.0 pM vs. 18.2 pM, P = 0.49). The receiver operating characteristics curve analysis for the benign ovarian tumor and ovarian cancer patients showed that HE4 showed a greater area under the curve with borderline significance when compared with CA-125 in both groups (0.93 vs. 0.85).ConclusionSerum HE4 levels may not only allow for the detection of ovarian cancer, but also allow for better differentiation of cases of ovarian cancer versus other benign ovarian tumors compared with serum CA-125.