Prognostic value of HE4 in advanced-stage, high-grade serous ovarian cancer: Analysis of HE4 kinetics during NACT, predicting surgical outcome and recurrence in comparison to CA125

Objectives To assess the prognostic value of human epididymis protein 4 (HE4) kinetics during and after neoadjuvant chemotherapy (NACT) cycles compared with cancer antigen 125 (CA-125), in predicting the surgical outcomes of interval debulking surgery (IDS) in patients with advanced-stage, high-grade serous ovarian cancer. Methods This retrospective cohort study was conducted at Severance Hospital in Seoul, South Korea and involved 123 women with high-grade serous epithelial ovarian, fallopian tube, or primary peritoneal cancer who were diagnosed between April 2015 and July 2020. Three outcomes were considered: the chemotherapy response score (CRS) by omentum, residual disease after IDS, and recurrence. Other clinical, imaging, and biological parameters at baseline, during NACT cycles, and pre- and postoperative time were collected and analyzed. Results We observed a substantial and gradual decrease in both CA-125 level (median from 1612 to 85.55 U/mL; p < 0.001) and HE4 level (514.7 to 87.7 pmol/L; p < 0.001) during NACT cycles, while pre-to-postoperative reduction was only significant for HE4 (median from 77.3 to 62.0 pmol/L (p < 0.001)). Of the total patients, 4.1% showed no response to NACT (chemoresistance) and 65.9% had a partial response. Residual disease was observed in 55 (44.7%) patients. Recurrence occurred in 90 patients (73.2%), with a median progression-free survival of 15.28 months. The percent reduction in CA-125 level– but not HE4 – during NACT was significantly associated with CRS (by omentum); the reduction in CA-125 during NACT cycles was higher when the CRS was found to be 3 and 2 (median = 96.4 [IQR = 8.3] and 93.7 [12.2] respectively) compared to score 1 (68.3 [34.1]), and the difference was statistically significant (p = 0.004). However, no significant association was observed between the percent reduction in CA-125 or HE4 levels during NACT and residual disease or recurrence. The normalization of HE4 – but not CA-125 – before surgery was predictive for surgery outcome; that is, an abnormal preop HE4 level was associated with a residual disease risk ratio of 2.72 (95% CI = 1.27–5.79). Conclusion Monitoring HE4 or CA-125 levels has low prognostic value in patients with advanced-stage, high-grade serous ovarian cancer who are treated with NACT followed by IDS. However, the preoperative level of the HE4 biomarker may be useful in identifying patients at higher risk for suboptimal cytoreductive surgery or who may require more extensive surgery. Further prospective studies are warranted to explore the prognostic utility of eventual combinations of clinical, radiological, and biological parameters, notably by using artificial intelligence-based models.