Association Between ERCC6-6530 Single Nucleotide Polymorphism And Prognosis Of Small Cell Lung Cancer Patients Treated With Platinum-based Chemotherapy

Background and aims: Platinum-based regimens are first line treatment for both small cell lung cancer (SCLC) and non-small cell lung cancer patients. SNPs of DNA repair genes have been found to be related to response of platinum-based regimen in non-small cell lung cancer patients. This study examined the association between functional -6530C→G polymorphism in ERCC6 and clinical outcomes in SCLC patients.Methods: This retrospective study recruited 260 SCLC patients. Genotypes of ERCC6 -6530C→G polymorphism were determined by PCR-based restriction fragment length polymorphism.Results: The frequencies of ERCC6 -6530 CC, CG, and GG genotypes were 43.1%, 46.9%, and 10%, respectively and they were not significantly associated with clinical stage. Genotypes were not related to response rate or time to progression in all the groups treated with CE, PE or regimens with either carboplatin or cisplatin. However, among 164 patients treated with CE regimen, patients with CG or GG genotype had a longer median survival time compared with CC genotype (23.0 versus 17.0 months, P = 0.009). Single variant survival analysis showed stage and surgical resection were also significant prognostic factors. Cox's multivariate analysis showed that ERCC6 genoptypes and clinical stage were independent prognostic factors. The hazard ratio of death for patients with CG or GG genotype was 0.62 (95% CI = 0.42-0.92, P =0.018) and it was 0.501(95% CI 0.326-0.769, P = 0.002) for patients with limited disease. In 43 patients treated with PE regimens, median survival time was 20 months and 16 months for patients with CC genotype and with CG and GG genotypes.Conclusion: ERCC6 -6530C→G polymorphism may be a prognostic factor in SCLC patients treated with CE regimen.