The quantified EGFR value by PNA clamping can be a predictor within EGFR mutated group = The quantified EGFR value by PNA clamping can be a predictor within EGFR mutated group

다국어 초록 (Multilingual Abstract)

Background: Epidermal growth factor receptor (EGFR) mutation is a reliable predictive factor for response to EGFR tyrosine kinase inhibitors (TKIs) compared to wild type. We investigated the quantified EGFR value can also predict response and survival within EGFR mutated group. Methods: This was a retrospective study of 836 lung cancer patients performed EGFR mutation test by peptidenucleic acid (PNA)-mediated clamping polymerase chain reaction (PCR) from January 2013 to December 2014. The efficiency of PCR clamping was determined by measuring the cycle threshold (Ct) value and the EGFR quantification was determined by corrected delta Ct (□Ct) value which was subtracted non-PNA corrected sample Ct value from standard Ct value. Results: The positivity of EGFR mutation was 32.3% and there were 235 single activating mutations (131 cases of 19 deletion and 104 cases of L858R). Response to EGFR-TKIs was significantly better in female (p＜0.001), non-smoker (p＝0.012), EGFR mutation (p＜0.001) and first line treatment group (p＜0.001). In EGFR single activating mutation group, the mean corrected □Ct value was 6. The high corrected □Ct group was significantly better response (70.9% vs. 54.9%, p＝0.022) and median progression-free survival (303.4 days vs. 223.9 days, p＝0.05). But overall survival was not different between two groups (379.7 days vs 356.2 days, p＝0.655). Conclusions: The quantified EGFR value by PNA-mediated PCR clamping can predict response and progression-free survival of EGFR-TKIs in patients with 19 deletion and L858R mutations.