[The efficacy and influence factors analysis of EGFR TKIs on patients with lung adenosquamous carcinoma]

Objective: To investigate the efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) on patients with lung adenosquamous carcinoma, and to analyze relative factors. Methods: From August 2007 to July 2017, 40 patients who were pathologically diagnosed as lung adenosquamous carcinoma in our hospital and received EGFR TKIs treatment were retrospectively analyzed. All patients underwent EGFR mutation detection, resulted in 11 wild type, 13 19Del, 13 21L858R mutations, and 3 uncommon EGFR mutations in 20 exon and 19/21 complex mutation. A higher frequency of EGFR mutation was found in non-smokers and patients with adenocarcinoma components over 50.0%. Results: Twenty-six (65.0%) patients had disease progression after EGFR TKIs treatment, with a median progression-free survival (PFS) of 5.5 months (95% CI 0.52-10.49 months). A total of 20 (50.0%) patients died with an median overall survival (OS) of 15 months (95% CI 11.03-18.97 months). Multivariate analysis showed that gender, age, smoking, histopathological subtypes, EGFR mutations, and brain metastasis had no influence on PFS (all P>0.05). Gender, age, smoking, histopathological subtypes, and the presence of brain metastasis during TKI treatment had no influence on OS (P>0.05), while EGFR mutation is the only influencing factor of OS (P<0.05) in the current study. Conclusions: EGFR TKIs had modest efficacy in lung adenosquamous carcinoma, especially in patients with EGFR mutation. Based on the pathological features, EGFR mutation and EGFR TKIs treatment should be introduced into the routine clinical practice to improve the survival of patients with lung adenosquamous carcinoma.