Comparison of EGFR mutations in blood and tumor tissue samples by allele-specific PCR / 临床与实验病理学杂志

ABSTRACT

Purpose To explore the clinical application value of allele specific PCR in detection of ctDNA EGFR mutations by comparing the epidermal growth factor receptor (EGFR)mutation in tumor tissue specimens and circulating tumor DNA (ctDNA) of lung cancer patients by allele-specific PCR.Methods 22 pairs of plasma samples and tumor tissue samples of non-small cell lung cancer (NSCLC) patients were collected and the corresponding cfDNA and tDNA were extracted.The cobas EGFR mutation test v2.0 and cobas EGFR mutation test were used to detected EGFR 18-21 exon mutation,respectively.Results Among 22 patients with NSCLC,there were 8 cases of EGFR mutations in plasma samples,so the mutation rate was 36.4％ (8/22).The presence of EGFR mutations in tumor samples was 13 cases,and the mutation rate was 59.1％ (13/22).EGFR mutation status of 16 patients in plasma samples was consistent with tumor tissues.The result of tDNA gene mutations was regarded as the standard.Sensitivity of gene mutations in ctDNA was 61.5％,and specificity was 100％.The concordance rate between result of tDNA and ctDNA was 72.7％.Conclusion Detection of ctDNA EGFR gene mutations by allele-specific PCR provides a new detection opportunity for patients unable to obtain tumor tissue specimens.