The role of epidermal growth factor receptor mutationsin advanced non-small cell lung cancer detected by liquid biopsy

Abstract

Objective To explore the clinical and therapeutic features in advanced non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) gene mutations and to evaluate the treatment of EGFR tyrosine kinase inhibitors (EGFR-TKI). Methods There were 107 advanced NSCLC patients with EGFR gene detected by liquid biopsy in this rearch, which were collected in retrospect and analyzed by statistical methods. Results The mutation rate of EGFR was 58.9%.There are 49 patients with EGFR mutation of single locusand 14 patients with EGFR mutation of multiple locus in 107 NSCLC patients.The mutation rates of male and female were 48.5% and 75.6% (χ2=7.685, P=0.006). The incidence of hepatic metastases of single-locus and multi-locus EGFR mutation was 12.2% and 35.7% (χ2=4.162, P=0.041). Patients treated by only medications with EGFR mutation had significant longer progression-free survival (PFS) than that without EGFR mutatuon (χ2=5.927, P=0.015) but OS had no significant difference between EGFR wile-type and mutant-type patients (χ2=3.526, P=0.06). Patients treated by medications with single-locus EGFR mutation had longer OS than that with mult-locus EGFR mutation (χ2=3.951, P=0.047), but PFS had no significant difference between single-locus and multi-locus EGFR mutation.Patients treated by EGFR-TKI with or without chemotherapy in the first-line treat menthad significant longer OS (χ2=8.632, P=0.003) compared to patients only treated by chemotherapy. Conclusions Female advanced NSCLC patients have significantly higher incidence of EGFR mutation, which is no significantly correlated with age, location of primary lesion, image-based types and organ of metastasis.EGFR-TKIs have obvious effects in treating advanced NSCLC patients with EGFR mutation.Patients may benefit more from using EGFR-TKIs early especially as first-line drugs.Advanced NSCLC patients with multi-locus EGFR mutation have higher incidence of hepatic metastasis, and have worst prognosis compared to that of single-locus EGFR mutation.Liquid biopsy is an effective approach for checking EGFR mutation in lung cancer. Key words: Receptor, epidermal growth factor; Carcinoma, non-small-cell lung; Liquid biopsy; Epidermal growth factor receptor tyrosine kinase inhibitors