Serum EGFR gene mutation status via second-generation sequencing and clinical features of patients with advanced lung...

Objective: To detect the serum epithelial growth factor receptor (EGFR) gene mutation status in patients with lung cancer via second-generation sequencing and to analyze its correlations with the clinical features of patients and its therapeutic effects. Methods: A total of 110 patients with non-small cell lung cancer (NSCLC) treated in our hospital were recruited as subjects of our study. The distribution of the EGFR gene mutation in patients was detected via second-generation sequencing and then patients were divided into mutant-type EGFR group (n=37) and wild-type EGFR group (n=73). The clinical features and therapeutic effects were compared between the two groups of patients. Results: A total of 5 kinds of EGFR gene mutation [19del (45.95%), L858R (43.24%), L861Q (5.41%), S768I (2.70%), and G719X (2.70%)] were detected via second-generation sequencing. In the mutant-type EGFR group, the proportions of female patients, patients with adenocarcinoma, and those with no history of smoking were high, and the differences were statistically significant (P<0.05). Moreover, there were statistically significant differences in gender, type of cancer, tumor-node-metastasis (TNM) staging, and smoking history between the mutant-type EGFR group and the wild-type EGFR group (P<0.05). Results of a multivariate logistic regression analysis showed that the EGFR gene mutation status was significantly associated with the type of cancer, gender, TNM staging, and smoking history of patients with NSCLC (P<0.05). The clinical effective rate of patients in the mutant-type EGFR group was significantly higher than that in the wild-type EGFR group (54.05% vs. 19.18%) while progression-free survival (PFS) was significantly longer than that in the wild-type EGFR group [(9.75±1.64) months vs. (5.51±0.40) months] (P<0.05). The expression level of carcinoembryonic antigen (CEA) in patients in the mutant-type EGFR group was apparently higher than that in the wild-type EGFR group, but the levels of carbohydrate antigen 125 (CA125), CY21-1 and squamous cell carcinoma-related antigen (SCC-Ag) were apparently lower than those in the wild-type EGFR group. There were statistically significant differences in the expression levels of serum tumor markers between the two groups (P<0.05). Conclusion: EGFR mutation status is closely related to the clinical features of NSCLC patients, such as gender, type of cancer, tumor staging, smoking history, and clinical effect. The second-generation sequencing is an important detection method to identify EGFR gene mutation status, which provides an applicable scaffold for the clinical treatment of patients.