{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"omics_type":["Unknown"],"volume":["10(3)"],"submitter":["Silveira C"],"pubmed_abstract":["<h4>Background</h4>Liquid biopsy allows the identification of targetable cancer mutations in a minimally invasive manner. In patients with advanced non-small cell lung cancer (NSCLC), droplet digital PCR (ddPCR) is increasingly used to genotype the epidermal growth factor receptor (<i>EGFR</i>) gene in circulating cell-free DNA (cfDNA). However, the sensitivity of this method is still under debate. The aim of this study was to implement and assess the performance of a ddPCR assay for detecting the <i>EGFR</i> T790M mutation in liquid biopsies.<h4>Methods</h4>A ddPCR assay was optimized to detect the <i>EGFR</i> T790M mutation in plasma samples from 77 patients with NSCLC in progression.<h4>Results</h4>Our ddPCR assay enabled the detection and quantification of the <i>EGFR</i> T790M mutation at cfDNA allele frequency as low as 0.5%. The mutation was detected in 40 plasma samples, corresponding to a positivity rate of 52%. The number of mutant molecules per mL of plasma ranged from 1 to 6,000. A re-biopsy was analyzed for 12 patients that had a negative plasma test and the mutation was detected in 2 cases. A second liquid biopsy was performed for 6 patients and the mutation was detected in 3 cases.<h4>Conclusions</h4>This study highlights the value of ddPCR to detect and quantify the <i>EGFR</i> T790M mutation in liquid biopsies in a real-world clinical setting. Our results suggest that repeated ddPCR tests in cfDNA may obviate tissue re-biopsy in patients unable to provide a tumor tissue sample suitable for molecular analysis."],"journal":["Translational lung cancer research"],"pagination":["1200-1208"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC8044487"],"repository":["biostudies-literature"],"pubmed_title":["Detection and quantification of <i>EGFR</i> T790M mutation in liquid biopsies by droplet digital PCR."],"pmcid":["PMC8044487"],"pubmed_authors":["Pantarotto M","Silveira C","Brysch E","Sousa AC","Janeiro A","Bruges-Armas J","Malveiro S","Madureira R","Canario D","Carmo-Fonseca M","Teixeira E","Guimaraes C","Felizardo M","Matos C","Nogueira F"],"additional_accession":[]},"is_claimable":false,"name":"Detection and quantification of <i>EGFR</i> T790M mutation in liquid biopsies by droplet digital PCR.","description":"<h4>Background</h4>Liquid biopsy allows the identification of targetable cancer mutations in a minimally invasive manner. In patients with advanced non-small cell lung cancer (NSCLC), droplet digital PCR (ddPCR) is increasingly used to genotype the epidermal growth factor receptor (<i>EGFR</i>) gene in circulating cell-free DNA (cfDNA). However, the sensitivity of this method is still under debate. The aim of this study was to implement and assess the performance of a ddPCR assay for detecting the <i>EGFR</i> T790M mutation in liquid biopsies.<h4>Methods</h4>A ddPCR assay was optimized to detect the <i>EGFR</i> T790M mutation in plasma samples from 77 patients with NSCLC in progression.<h4>Results</h4>Our ddPCR assay enabled the detection and quantification of the <i>EGFR</i> T790M mutation at cfDNA allele frequency as low as 0.5%. The mutation was detected in 40 plasma samples, corresponding to a positivity rate of 52%. The number of mutant molecules per mL of plasma ranged from 1 to 6,000. A re-biopsy was analyzed for 12 patients that had a negative plasma test and the mutation was detected in 2 cases. A second liquid biopsy was performed for 6 patients and the mutation was detected in 3 cases.<h4>Conclusions</h4>This study highlights the value of ddPCR to detect and quantify the <i>EGFR</i> T790M mutation in liquid biopsies in a real-world clinical setting. Our results suggest that repeated ddPCR tests in cfDNA may obviate tissue re-biopsy in patients unable to provide a tumor tissue sample suitable for molecular analysis.","dates":{"release":"2021-01-01T00:00:00Z","publication":"2021 Mar","modification":"2025-04-04T21:24:57.295Z","creation":"2025-04-04T21:24:57.295Z"},"accession":"S-EPMC8044487","cross_references":{"pubmed":["33889502"],"doi":["10.21037/tlcr-20-1010"]}}