Detection of EGFR mutations in non - small cell lung cancer in Vietnam by using PYROSEQUENCING

Abstract

Background: EGFR gene mutations occur in the early stages and have a high frequency in non-small cell lung cancer (NSCLC). Targeted therapy has emerged as an important strategy in the treatment of NSCLC. Detection of genetic mutations is of great significance to help physicians choose the appropriate treatment regimens to improve therapeutic response. Objectives: This study was performed to determine the EGFR mutation rate in Vietnamese NSCLC patients, which can be used to predict clinical response to small-molecule tyrosine kinase inhibitors for the treatment of lung cancer. Methods: From June to December 2015, 64 patients were detected for EGFR gene mutations. Polymerase chain reaction (PCR) was used to amplify the region containing exons 18-21 of EGFR from formalin-fixed, paraffin-embedded lung carcinoma tissues. Then EGFR mutations were analyzed by using pyrosequencing. Results: 43/64 (67.2%) patients had EGFR mutations, including 1 case with G719S mutation in exon 18 (2.3%), 25 deletions in exon 19 (58.1%), 8 cases with T790M mutation in exon 20 (18.6%), 13 cases with L858R mutation (30.2%) and 1 with L861Q mutation (2.3%) in exon 21. There were 5 cases that had 2 different mutations. Conclusion: High EGFR mutation rate occurs in Vietnamese NSCLC patients with 67.2% (43/64). Pyrosequencing is a good complementary technique in determining EGFR mutations in NSCLC patients. Keywords: Non-small cell lung cancer; EGFR mutation; Targeted therapy; Pyrosequencing.