Prognostic Factors in Patients with Advanced Lung Adenocarcinoma Treated with Icotinib

Objective To investigate the relationship between the treatment of EGFR-TKI icotinib and the prognosis of advanced lung adenocarcinoma patients with EGFR mutation. Methods Patients with advanced lung adenocarcinoma who had EGFR19 and 21 gene mutations and were treated with EGFR-TKI icotinib were enrolled. The relationships of clinical features, EGFR gene mutation subtypes, and different sites with patients'prognosis were analyzed. Results A total of 101 patients with advanced lung adenocarcinoma were included in this study, including 58 cases (57.4%) of EGFR gene exon 19 deletion mutation (EGFR Del19) and 43 cases (42.6%) of EGFR gene exon 21 point mutation (EGFR L858R). The objective response rate was 63.4%. The mPFS and mOS were 13 months and 27 months, respectively. In addition, the mPFS and mOS of EGFR Del19 and EGFR19 mutation 746-750 were higher than those of EGFR L858R and other EGFR mutations, respectively. Meanwhile, multivariate analysis showed that the number of metastatic sites and pleural metastasis were independent influencing factors of patients'OS (P=0.027; P=0.041). The mOS of patients with the number of metastatic sites ≤3 and without pleural metastasis were 29 and 27 months, respectively. Conclusion There is no significant difference found in overall survival of advanced lung adenocarcinoma patients treated with icotinib among different EGFR mutation subtypes and sites. Herein, the overall survival time is longer in patients with less than three metastatic sites and without pleural metastasis.