Relation between the gene status of epidermal growth factor receptor and efficacy of the first-line tyrosine kinase inhibitor in patients with advanced non-small cell lung cancer / 肿瘤研究与临床

ABSTRACT

Objective To explore the relationship between mutation status of epidermal growth factor receptor (EGFR) and efficacy of EGFR tyrosine kinase inhibitor (EGFR-TKI) in patients with advanced nonsmall ccll lung cancer (NSCLC).Methods The data of 72 outpatients and inpatients with stage Ⅲ b/ⅣNSCLC diagnosed by histopathology and harbored EGFR-activating mutations (exon 19 and exon 21) from January 2008 to December 2013 in Xuzhou Cancer Hospital were collected.All of them received first-line EGFR-TKI.The relationships between EGFR gene status and response rate or progression-free survival (PFS)were analyzed.Results Of the 72 patients with EGFR mutation,37 patients harbored exon 19 deletion,and 35 patients harbored exon 21 L858R point mutation.The efficacies of all patients were assessable.The objective response rate (ORR) was 63.9 ％ (46/72) and disease control rate (DCR) was 79.2 ％ (57/72) in all patients,including 2 cases of complete remission (CR),44 cases of partial remission (PR),1 1 cases stable disease (SD) and 15 cases of disease progression (PD).Patients with exon 19 deletion had a higher ORR [75.7 ％ (28/37) vs 51.4 ％ (18/35),P =0.032] and a higher DCR [89.2 ％ (33/37) vs 68.6 ％ (24/35),P =0.031]than patients with exon 21 L858R mutation.The PFS of patients with exon 19 deletion was significantly longer than that of patients with exon 21 L858R mutation (12.0 months vs 9.5 months,P =0.030).Cox multivariate analysis indicated that the gender,histological type,smoking history were the major influence factors of PFS.The differences of toxicity between the two groups were not significant.Conclusion EGFR-activating mutation is a predictor for PFS and ORR of first-line EGFR-TKI in patients with advanced NSCLC.