Detection of Epidermal Growth Factor Receptor (EGFR) Gene Mutation in Formalin Fixed Paraffin Embedded Tissue by Polymerase Chain Reaction-Single Strand Conformational Polymorphism (PCR-SSCP) in Non-Small Cell Lung Cancer in the Northeastern Region of Thailand.

Background

The use of targeted specific genes in therapeutic and treatment decisions has been considered for lung cancer. The epidermal growth factor receptor (EGFR) gene, which is over expressed in non-small cell lung cancer (NSCLC), was considered as one of the targeted specific genes. EGFR mutations in exons 18–21, which encode a portion of the EGFR kinase domain, were found in NSCLC patients and were associated with the response of EGFRtyrosine kinase inhibitors (EGFR-TKIs). Therefore, a molecular technique for EGFR mutation detection has important benefits for therapy in NSCLC patients. This study aims to determine the EGFR mutations in patients with NSCLC using polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) in exons 18-21.

Methods

DNA samples were extracted from formalin fixed paraffin embedded tissues of NSCLC patients who attended hospital. The extracted DNA was used as a template for the EGFR gene amplification.

Results

Occurrence of EGFR mutations were found in 29 out of 50 cases (58%).The frequency of EGFR mutations by first PCR at exon 18, 19, 20 and 21 were 6 (12%), 19 (38%) 20 (40%) and at 21 (42%), respectively. By PCR-SSCP, the frequencies of EGFR mutations at exon 18, 19, 20 and 21 were 3(6%), 18(36%), 23(46%) and 13(26%), respectively. All of the mutations found were in agreement with DNA sequencings.

Conclusion

The high frequency of EGFR mutations in NSCLC suggests that PCR-SSCP is a efficient screening method and useful for treatment plan.