Excision repair cross-complementation group 1 protein overexpression as a predictor of poor survival for high-grade serous ovarian adenocarcinoma

Abstract Objective The excision repair cross-complementation group 1 (ERCC1) expression is a predictor of survival after surgical treatment for several malignancies. Its overexpression has been reported as a marker of platinum resistance in lung cancer. However, the relevance of ERCC1 expression in ovarian cancer (OC) is the subject of controversy, both as a predictive parameter for platinum resistance and because of its association with poor prognosis. Therefore, we performed a retrospective study investigating ERCC1 expression and its correlation with patients' survival in OC. Methods We analyzed the ERCC1 protein expression using four different ERCC1 antibodies (clone 8F1) with different staining protocols. Immunohistochemistry was performed on multi-tissue microarrays (77 patients with primary serous ovarian cancer treated between 1999 and 2004; median age at diagnosis 67 years; range 32 to 88 years; 90% FIGO III + IV). In all cases cytoreductive surgery was followed by platinum-based chemotherapy. Results The Kaplan–Meier analysis revealed that the survival of patients with ERCC1-negative OCs (n = 45; 62%) was significantly better (median survival 50.0 months) compared with the ERCC1-positive group (n = 32; 38%; 20 months; p = 0.004). Furthermore, ERCC1 expression was of prognostic relevance (p = 0.002) in the case of negative expression in patients with residual tumor, where a higher survival rate was observed (median survival 30 months compared to 7.8 months in the ERCC1-positive group). Conclusions ERCC1 protein overexpression may act as a prognostic marker for poor survival of high-grade OC even in patients operated with residual disease.