Analysis of real-word mutations of lung cancer driver genes in five regions of China

BACKGROUND: The aim of this study was to analyse the epidemiological characteristics and clinical features of the three driver genes EGFR, ALK and ROS1 in Chinese patients with non-small-cell lung cancer (NSCLC). METHODS: EGFR mutations, ALK fusions and ROS1 rearrangements were detected simultaneously by quantitative real-time PCR. Subgroup analyses were performed for adenocarcinoma and squamous cancer. The Chi-square test and multivariate logistic regressive analysis were used to analyse the associations between gene alterations and clinical features. RESULTS: A total of 3,081 patients with pathologically confirmed NSCLC from five sites in China were enrolled, among whom 1,449 (47.03%) had EGFR, ALK and/or ROS1 alterations. In adenocarcinoma, the alteration rates of EGFR, ALK and ROS1 were 50.6% (1,193/2,360), 6.3% (148/2,360), and 1.6% (38/2,360), respectively. EGFR and EML4-ALK coexisted in 16 cases (0.5%), while EGFR and ROS1 coexisted in 1 case (0.03%). Sex, smoking status, and tumour stage were significantly correlated with the EGFR mutation; age and smoking status were correlated with EML4-ALK; and age and tumour stage were correlated with ROS1. In squamous cancer, the alteration rates of EGFR, ALK and ROS1 were 7% (34/488), 2.9% (14/488) and 0% (0/488), respectively. Sex and smoking history were associated with EGFR, and sex was the only independent predictor of EGFR. The EGFR gene mutation sites were mainly 19del (557/1,263; 44.1%) and 21 exon L858R (575/1,263; 45.5%). More uncommon EGFR mutation types were present in 10.4% (131/1,263) of patients. Patients with EGFR, ALK, and/or ROS1 alterations had different epidemiological characteristics and clinical features. CONCLUSIONS: This real-word study of alterations in driver genes in a large population in China revealed unique epidemiological characteristics and clinical features in Chinese patients with NSCLC.