Prognostic Significance of HE4 Tissue Expression in Serous Epithelial Ovarian Carcinoma

Neerja BhatlaBackground  Human Epididymis protein 4 (HE4) is expressed in ovarian cancer. Preoperative serum testing is still not widely available. This pilot study aimed to investigate the magnitude of expression of HE4 in tissue sections of serous epithelial ovarian carcinoma, its correlation with clinical outcome, and the feasibility of HE4 immunohistochemistry as a prognostic marker. Materials and Method  In this ambispective study, immunohistochemistry (IHC) was used to evaluate tissue sections of ovarian serous epithelial carcinoma at primary cytoreductive surgery. On HE4 immunohistochemistry (IHC), the magnitude of HE4 expression was assessed categorically as high or low HE4 expression and semiquantitatively by the H-score, and correlated with clinical outcome in terms of survival status, progression-free survival, and overall survival. Results  Of 32 cases, most ( n  = 31, 96.8%) were positive for HE4 IHC. The mean age was 49 ± 8.2 years; 29 (90.6%) patients were in FIGO stage IIIC; 25 (78.9%) had ≥1cm residual disease after surgery; 31 (96.8%) received adjuvant chemotherapy, either 3-weekly ( n  = 25, 81.2%) or dose-dense weekly ( n  = 6, 18.8%) regimen. The majority ( n  = 31, 96.8%) had a high-grade tumor, of whom 19 (59.4%) had high HE4 expression and 13(40.6%) patients had H-score in the range of 5 to 8. The mean H-score was 6.97 ± 3.61 (range 0 to 12). The overall survival of the study population at 64 months was 36.65% (95% CI: 8.59-66.34), with median overall survival of 59 months. A new scoring system was developed combining categorical HE4 expression and serum CA-125 levels; the combination of HE4 expression with postoperative CA-125 levels was found to be the best prognostic marker for overall survival ( p  = 0.05). A composite score of 2 identified patients with poor progression-free survival (HR 4.64, p  = 0.039) and overall survival (HR 5.45, p  = 0.05). Conclusion  The new composite scoring system using HE4 IHC with postoperative serum CA-125 levels offers an extremely useful option for prognosticating patients with serous epithelial ovarian carcinoma than serum CA-125 alone. This is useful where preoperative records are not available to the treating clinician.