Objective: The purpose of the study was to investigate whether single-nucleotide polymorphisms of deoxyribonucleic acid repair gene excision repair cross-complementing group 1 at codon 118 and X-ray repair cross-complementing group 3 at codon 241 affected clinical outcomes in advanced non-small cell lung cancer patients receiving first-line platinum-based chemotherapy.
Methods: A total of 130 patients treated with platinum-based doublets were examined for genotyping of excision repair cross-complementing group 1 118 and X-ray repair cross-complementing group 3 241 in peripheral blood lymphocytes with the method of the TaqMan assay plus the real-time polymerase chain reaction method. Multivariate logistic or Cox's regression analyses were used to adjust for possible confounding variables.
Results: There were no differences in clinical characteristics among the different single-nucleotide polymorphisms. Overall response rate in the 130 patients was 20% with 85.4% of disease control rate. Followed up to 31 March 2008, there were 47 patients still alive. Overall survival was 15 months. No relationship was found between excision repair cross-complementing group 1 or X-ray repair cross-complementing group 3 single-nucleotide polymorphisms and tumor response to platinum-based chemotherapy. A significant correlation was found between excision repair cross-complementing group 1 118 C/T single-nucleotide polymorphisms and survival (P = 0.003). In the multivariate model, the survival was highly related with excision repair cross-complementing group 1 118 C/T or T/T genotypes and tumor response to chemotherapy.
Conclusions: Overall survival was significantly improved in the patients with excision repair cross-complementing group 1 118 T/T or C/T treated by platinum-based chemotherapy.