Diagnostic value of urinary-to-serum human epididymis protein 4 ratio in ovarian cancer.

Human epididymis protein 4 (HE4) is one of the best-known tumor markers for ovarian cancer (OC). Emerging evidence indicates that the evaluation of serum HE4 (S-HE4) levels may be problematic when patients have chronic kidney disease (CKD). Assaying urine for HE4 levels is non-invasive alternative for the diagnosis of OC. However, whether the combined detection of S- and urinary HE4 (U-HE4) levels distinguishes OC from CKD remains unknown. To investigate this issue, the present study recruited 31 female patients with OC, 38 female patients with CKD, and 36 healthy control (HC) females. Serum and urine samples were preoperatively collected for HE4 level detection. Receiver operating characteristic (ROC) curves were constructed to assess the diagnostic performance of S-HE4 level, U-HE4 level and the ratio of urinary-to-serum HE4 level (R-HE4). Data from the current study indicated that serum HE4 levels in the OC and CKD groups were significantly higher than that in the HC group. The U-HE4 level in the OC group was significantly higher than that in the CKD and HC groups. The highest R-HE4 was observed in the HC group, followed by the OC group, and the lowest R-HE4 was observed in the CKD group. ROC analysis demonstrated that the R-HE4 was useful in differentiating OC from CKD and HC. Based on the diagnostic interval of optimal cut-off values from 36.85 to 96.15, the sensitivity and specificity of R-HE4 in differentiating OC patients from non-OC patients were 82.6 and 85.4%, respectively. Thus, the combined detection of S- and U-HE4 levels facilitates the diagnosis of OC, and R-HE4 is an effective marker for differentiating OC from CKD.