Low expression of excision repair cross-complementation group-1 protein predicts better outcome in patients with locally advanced nasopharyngeal cancer treated with concurrent chemoradiotherapy

Abstract

Aims and background: Cisplatin-based concurrent chemoradiotherapy is the standard treatment of locally advanced nasopharyngeal cancer. We conducted this study to assess the value of excision repair cross-complementation group 1 (ERCC1) protein expression in predicting the clinical outcome of patients with locally advanced nasopharyngeal cancer who were treated with cisplatin-based concurrent chemoradiotherapy.

Methods and study design: We employed immunohistochemical analysis to determine the expression of ERCC1 protein among 66 patients with locally advanced nasopharyngeal cancer who were treated with concurrent chemoradiotherapy. The relationship of ERCC1 expression to clinical outcome was analyzed.

Results: There were no statistically significant differences in gender, age, T stage, N stage, clinical staging and treatment method between the high ERCC1 expression and low ERCC1 expression groups. Fifty-eight patients (87.88%) had a complete response and 8 (12.12%) a partial response. Of the 34 patients with high ERCC1 expression, 10 (29.41%) relapsed, compared with 4 of 32 (12.5%) patients with low ERCC1 expression (P = 0.041). The 5-year overall survival rate was 58.82% in patients with high ERCC1 expression and 84.37% in patients with low ERCC1 expression (P = 0.022). Multivariate analysis showed that low expression of ERCC1 was a significant independent prognostic factor for better overall survival (P = 0.026).

Conclusions: Low ERCC1 expression is associated with prolonged survival in patients with locally advanced nasopharyngeal cancer receiving cisplatin-based concurrent chemoradiotherapy. ERCC1 expression may become a molecular marker in predicting the clinical outcome of these patients.