Peripheral Blood for Epidermal Growth Factor Receptor Mutation Detection in Non-Small Cell Lung Cancer Patients

摘要

OBJECTIVE:It is important to analyze and track Epidermal Growth Factor Receptor (EGFR) mutation status for predicting efficacy and monitoring resistance throughout EGFR-tyrosine kinase inhibitors (TKIs) treatment in non-small cell lung cancer (NSCLC) patients. The objective of this study was to determine the feasibility and predictive utility ofEGFRmutation detection in peripheral blood.METHODS:Plasma, serum and tumor tissue samples from 164 NSCLC patients were assessed forEGFRmutations using Amplification Refractory Mutation System (ARMS).RESULTS:Compared with matched tumor tissue, the concordance rate ofEGFRmutation status in plasma and serum was 73.6% and 66.3%, respectively. ARMS forEGFRmutation detection in blood showed low sensitivity (plasma, 48.2%; serum, 39.6%) but high specificity (plasma, 95.4%; serum, 95.5%). Treated with EGFR-TKIs, patients withEGFRmutations in blood had significantly higher objective response rate (ORR) and insignificantly longer progression-free survival (PFS) than those without mutations (ORR: plasma, 68.4% versus 38.9%, P = 0.037; serum, 75.0% versus 39.5%, P = 0.017; PFS: plasma, 7.9 months versus 6.1 months, P = 0.953; serum, 7.9 months versus 5.7 months, P = 0.889). In patients with mutant tumors, those withoutEGFRmutations in blood tended to have prolonged PFS than patients with mutations (19.7 months versus 11.0 months, P = 0.102).CONCLUSIONS: EGFRmutations detected in blood may be highly predictive of identical mutations in corresponding tumor, as well as showing correlations with tumor response and survival benefit from EGFR-TKIs. Therefore, blood forEGFRmutation detection may allow NSCLC patients with unavailable or insufficient tumor tissue the opportunity to benefit from personalized treatment. However, due to the high false negative rate in blood samples, analysis forEGFRmutations in tumor tissue remains the gold standard.