Efficacy of first line epidermal growth factor receptor tyrosine kinase inhibitor in advanced lung adenocarcinoma patients with different epidermal growth factor receptor mutation status / 肿瘤研究与临床

ABSTRACT

Objective To investigate the clinical characteristics of advanced lung adenocarcinoma patients with different epidermal growth factor receptor(EGFR) mutation status, and to analysis the efficacy of first line epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) for these patients. Methods The clinical data of 193 advanced lung adenocarcinoma patients with EGFR gene sensitive mutation (exon 19 deletion and exon 21 L858R mutation) were collected in the Beijing Hospital from January 2011 to December 2015.The relationship between EGFR mutation status and objective response rate (ORR), progression free survival (PFS) were analyzed. Results Of the 193 patients, 104 patients expressed exon 19 deletion, 89 patients expressed exon 21 L858R mutation.Compared with the patients with EGFR exon 21 L858R mutation, the patients with EGFR exon 19 deletion were younger, and the patients younger than 60 years old accounted for 47.1 %(49/104),while the L858R point mutation in this age group was 28.1 %(25/89),and the difference was statistically significant (χ2= 7.343, P = 0.007), but there were no significant differences in gender, smoking status, and metastasis site (all P>0.05). The ORR of patients with exon 19 deletion were same to those of patients with exon 21 L858R mutation [71.2 % (47/66) vs. 61.1 % (33/54), χ2= 1.364, P= 0.243]. The median PFS of patients with exon 19 deletion was significantly higher than that of patients with exon 21 L858R mutation (11.0 months vs. 8.6 months, U= 1.984, P = 0.046). Conclusions Lung adenocarcinoma with EGFR exon 19 deletion is associated with longer PFS compared with those with exon 21 L858R mutation. Different mutation status of EGFR can be used as a predictor of PFS in patients with advanced lung adenocarcinoma treated with first-line EGFR-TKI.