EGFR and lung cancer: It has been approved in the United States, Europe, and Asian countries with the purpose to detect of EGFR mutations with high sensitivity and specificity.[17] PCR-based methods have been used in the determination of allele frequency in DNA samples.[18] Thus, the Therascreen EGFR RGQ PCR kit assay was used in our study to determine the content of mutant EGFR DNA in lung cancer cells and tissues.