Increase EGFR Mutations Detection Rate in Lung Adenocarcinoma by Real-Time PCR Screening Followed by Direct Sequencing.

Background: Recently, a number of small-molecule tyrosine kinase inhibitors (TKIs) have been developed to target the ATP-binding cleft of the epidermal growth factor receptor (EGFR). The presence of EGFR mutations in non-small cell lung cancer (NSCLC) correlates with the responsiveness to TKIs. Therefore, the identification of EGFR mutations before the administration of TKIs of NSCLC has become important. The aim of the present study was to investigate the occurrence of EGFR mutations in the southern Taiwanese population with NSCLC using a combination of real-time polymerase chain reaction (PCR) kit and direct sequencing.

Methods: In the present study, DNAs were extracted from 249 cases of formalin-fixed, paraffin-embedded NSCLC samples for clinical EGFR mutational analysis by real-time PCR kit and direct sequencing.

Results: The results showed that the frequency of EGFR mutations is 63% in the southern Taiwanese population. Most of the EGFR mutations are located at exons 19 and 21. In addition, we indicated that a combination of real-time PCR kit and direct sequencing increases the rate of mutation by 4%. Direct sequencing revealed 9 EGFR mutations including 6 reported EGFR mutations and 3 novel EGFR mutations.

Conclusions: In the present study, we have demonstrated that a combination of real-time PCR kit and direct sequencing increases the detection rate of EGFR mutations. Therefore, our proposed EGFR mutation detection strategy could be applied in clinical settings. In addition, our results indicated the prevalence of EGFR mutational status in the southern Taiwanese population.