Expression of Excision Repair Cross-Complementation Group 1 as Predictive Marker for Nasopharyngeal Cancer Treated With Concurrent Chemoradiotherapy

Purpose Cisplatin-based concurrent chemoradiotherapy is the standard treatment of nasopharyngeal cancer. The expression of excision repair cross-complementation group 1 (ERCC1) has been reported to be associated with resistance to platinum-based chemotherapy. We evaluated whether ERCC1 expression could predict the treatment response and survival outcome of patients with locally advanced nasopharyngeal cancer who were treated with cisplatin-based concurrent chemoradiotherapy. Methods and Materials Immunohistochemistry was used to examine the expression of ERCC1 in nasopharyngeal tumor tissue. Patients were categorized into either a resistant or sensitive group depending on their treatment response outcome. A total of 77 patients were assessed in the present study. Results The resistant and sensitive groups included 25 and 52 patients, respectively. ERCC1 expression was positive in the tumor tissue for 39 of the 77 patients (51%). Significantly more ERCC1-negative tumors were in the sensitive group than in the resistant group ( p = .035). In terms of survival outcome, univariate analysis determined that patients with ERCC1-negative tumors had longer disease-free survival ( p = .076) and overall survival ( p = .013) than patients with ERCC1-positive tumors. Multivariate analysis determined that negative ERCC expression in tumors was an independent predictor for prolonged overall survival (hazard ratio, 0.14; 95% confidence interval, 0.03–0.71). Conclusion These results suggest that ERCC1 expression might be a useful predictive marker in patients with locally advanced nasopharyngeal cancer who are under consideration for cisplatin-based concurrent chemoradiotherapy.