Polymorphisms of ERCC1 and XRCC1 predict the overall survival of advanced gastric cancer patients receiving oxaliplatin-based chemotherapy.

The aim of the present study was to evaluate the clinical outcome of excision repair cross-complementing protein 1 (ERCC1) and X-ray repair cross-complementing protein 1 (XRCC1) gene polymorphisms in 89 patients receiving oxaliplatin/5-fluorouracil-based chemotherapy as a first-line treatment regimen for advanced gastric cancer. ERCC1 codon 118C/T and XRCC1 codon 399A/G polymorphisms were identified using quantitative polymerase chain reactions, and the associations between disease control rate (DCR), median overall survival (mOS) and gene polymorphisms were analyzed. Following two cycles of chemotherapy, a complete response was observed in two patients, a partial response in 18 patients, stable disease in 38 patients and progressive disease in 31 patients. It was determined that ERCC1 and XRCC1 polymorphisms are not associated with DCR (P=0.662 and P=0.631, respectively). The mOS of patients exhibiting ERCC1 and XRCC1 polymorphisms was eight months, and although no significant association was identified between ERCC1 codon 118 genotypes and mOS (P>0.05), the combination of ERCC1 and XRCC1 polymorphisms, as well as the specific presence of the XRCC1 codon 399A/G polymorphism, was associated with mOS (P<0.05). Thus, the present study indicated that the XRCC1 polymorphism and the combination of XRCC1 and ERCC1 polymorphisms were independent predictors for mOS; however, the XRCC1 and ERCC1 genes were not able to predict the DCR.