Background: Our previous study identified rs9387478 as a new susceptibility locus associated with lung cancer in never-smoking women in Asia; however, the clinical and prognostic significance of this finding is not known.
Methods: We analyzed the relationship between the rs9387478 single nucleotide polymorphism and i) clinical parameters and ii) overall survival time in 505 female nonsmoking lung cancer patients, using the chi-square test and Kaplan-Meier analysis with the log-rank test, respectively. We further established the epidermal growth factor receptor (EGFR) mutation status and assessed its association with rs9387478 genotypes as well as the efficacy of EGFR tyrosine kinase inhibitors.
Results: The frequency of the AA genotype was significantly higher in the EGFR-mutation-negative group than in the EGFR-mutation-positive group (32% vs. 16%, χ2 = 13.025, p = 0.011). Patients with the CC genotype had a better overall survival time than patients with the AA/AC genotype (median survival time: 54.2 vs. 32.9 months, χ2 = 4.593, p = 0.032). The distribution of rs9387478 genotypes differed according to the clinical disease stage.
Conclusions: This study indicates that the rs9387478 genotype was associated with overall survival in nonsmoking female patients with lung cancer, although it was not significant after adjusting for multiple testing. The identification of the location of the rs9387478 single nucleotide polymorphism in the genomic interval containing the DCBLD1 and ROS1 genes, together with the finding that the rs9387478 polymorphism correlates with EGFR mutation status, may have important implications for therapeutic approaches targeting EGFR or ROS1 in patients with lung cancer.