Expression level of serum human epididymis 4 and its prognostic significance in human non-small cell lung cancer.

The prognostic significance of serum human epididymis protein 4 (HE4) levels in human NSCLC among a Chinese population has not been investigated. The purpose of this study was to evaluate the prognostic significance of serum HE4 level in patients with NSCLC among a Chinese population. Serum HE4 expression levels were measured by enzyme-linked immunosorbent assay (ELISA). The overall survival (OS) analyzed by log-rank test, and survival curves was plotted according to Kaplan-Meier. The COX proportional hazards regression model was used to determine the joint effects of several variables on survival. Serum HE4 level was found to be significantly higher in patients with NSCLC than that of controls (13.76 ± 5.01 ng/ml vs. 5.09 ± 1.25 ng/ml, P < 0.01). High HE4 expression was correlated with TNM stage (P = 0.003), lymph node metastases (P = 0.007), and distant metastases (P < 0.001). Furthermore, patients with high serum HE4 level had a significantly lower 5-year OS rate (34.0% vs. 59.7%; P = 0.022) than those with low serum HE4 level. In a multivariate Cox model, we found that HE4 expression was an independent poor prognostic factor for 5-year OS (hazards ratio [HR] = 3.654, 95% confidence interval [CI] = 2.753-11.981, P = 0.019) in NSCLC. In conclusion, the detection of HE4 levels in the serum might serve as a new tumor biomarker in the prognosis of NSCLC among Chinese population.