Purpose: The aim of this study was to determine whether the ERCC1 expression is effective to predict the clinical outcomes of patients with advanced gastric cancer (AGC) and who were treated with cisplatin-based first-line chemotherapy.
Materials and methods: A total of 89 measurable AGC patients received cisplatin and capecitabine, with or without epirubicin, as a part of a randomized phase II study. Patients were included for the current molecular analysis if they had received two or more cycles of chemotherapy, their objective tumor responses were measured and if their paraffin-embedded tumor samples were available. The ERCC1 expression was examined by performing immunohistochemical (IHC) staining, and the patients were divided into two groups (positive or negative) according to the presence of IHC staining of the tumor cell nuclei.
Results: Of the 32 eligible patients, 21 patients (66%) had tumor with a positive expression of ERCC1 and the remaining 11 patients had tumor with a negative ERCC1-expression. The ERCC1-negative patients achieved a higher response rate than that of the ERCC1-positive patients (44% vs. 28%, respectively), although the difference was not statistically significant (p=0.42). The median survival time for the all patients was 14.6 months (95% CI: 13.6 to 15.6 months). The one-year survival rate was similar for the ERCC1-negative patients (61%) and the ERCC1-positive patients (70%).
Conclusion: In the current study, the tumor ERCC1 expression by IHC staining could not predict the clinical response or survival of AGC patients who were treated with cisplatin-based first-line chemotherapy. The ERCC1 protein expression does not appear to be a useful tool for the selection of tailored chemotherapy for these patients.
Keywords: Capecitabine; Cisplatin; ERCC1; Immunohistochemical stain; Stomach neoplasms.