ERCC1 as a Predictive Marker for FOLFOX Chemotherapy in an Adjuvant Setting

PURPOSE The purpose of this study was to identify the excision repair cross-complementation group 1 (ERCC1) as a predictive marker for FOLFOX adjuvant chemotherapy in stages II and III colon cancer patients. METHODS A total of 166 high risk stages II and III colon cancer patients were retrospectively enrolled in this study, and data were collected prospectively. They underwent a curative resection followed by FOLFOX4 adjuvant chemotherapy. We analyzed ERCC1 expression in the primary colon tumor by using immunohistochemical staining. The oncological outcomes included the 5-year disease-free survival (DFS) rate. The DFS was analyzed by using the Kaplan-Meier method with the log-rank test. A Cox proportional hazard model was used for the prognostic analysis. RESULTS ERCC1-positive expression was statistically significant in the older patients (P = 0.032). In the multivariate analysis, the prognostic factors for DFS were female sex (P = 0.016), N stage (P = 0.009), and postoperative carcinoembryonic antigen level (P = 0.001), but ERCC1 expression was not a statistically significant prognostic factor for DFS in the univariate analysis (P = 0.397). The 5-year DFS rate was not significantly associated with the ERCC1 expression in all patients (P = 0.396) or with stage III disease (P = 0.582). CONCLUSION We found that ERCC1 expression was not significantly correlated with the 5-year DFS as reflected by the oncologic outcomes in patients with high-risk stages II and III colon cancer treated with FOLFOX adjuvant chemotherapy.