{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T20:59:04Z","timestamp":1773089944962,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,7,28]],"date-time":"2021-07-28T00:00:00Z","timestamp":1627430400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Introduction: Cell-free DNA (cfDNA) analysis offers a non-invasive method to identify sensitising and resistance mutations in advanced Non-Small Cell Lung Cancer (NSCLC) patients. Next-generation sequencing (NGS) of circulating free DNA (cfDNA) is a valuable tool for mutations detection and disease\u2032s clonal monitoring. Material and methods: An amplicon-based targeted gene NGS panel was used to analyse 101 plasma samples of advanced non-small cell lung cancer (NSCLC) patients with known oncogenic mutations, mostly EGFR mutations, serially collected at different clinically relevant time points of the disease. Results: The variant allelic frequency (VAF) monitoring in consecutive plasma samples demonstrated different molecular response and progression patterns. The decrease in or the clearance of the mutant alleles was associated with response and the increase in or the emergence of novel alterations with progression. At the best response, the median VAF was 0% (0.0% to 3.62%), lower than that at baseline, with a median of 0.53% (0.0% to 9.9%) (p = 0.004). At progression, the VAF was significantly higher (median 4.67; range: 0.0\u201336.9%) than that observed at the best response (p = 0.001) and baseline (p = 0.006). These variations anticipated radiographic changes in most cases, with a median time of 0.86 months. Overall, the VAF evolution of different oncogenic mutations predicts clinical outcomes. Conclusion: The targeted NGS of circulating tumour DNA (ctDNA) has clinical utility to monitor treatment response in patients with advanced lung adenocarcinoma.<\/jats:p>","DOI":"10.3390\/cells10081912","type":"journal-article","created":{"date-parts":[[2021,7,28]],"date-time":"2021-07-28T05:23:48Z","timestamp":1627449828000},"page":"1912","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Liquid Biopsy for Disease Monitoring in Non-Small Cell Lung Cancer: The Link between Biology and the Clinic"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3549-0770","authenticated-orcid":false,"given":"Maria Gabriela O.","family":"Fernandes","sequence":"first","affiliation":[{"name":"Pulmonology Department, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"},{"name":"Faculty of Medicine, University of Porto, Alameda Prof. Hernani Monteiro, 4200-319 Porto, Portugal"},{"name":"Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), 4200-135 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8231-1608","authenticated-orcid":false,"given":"Catarina","family":"Sousa","sequence":"additional","affiliation":[{"name":"Pulmonology Department, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"}]},{"given":"Joana","family":"Pereira Reis","sequence":"additional","affiliation":[{"name":"Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), 4200-135 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health (i3S), University of Porto, Rua Alfredo Allen, 4200-135 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5934-5201","authenticated-orcid":false,"given":"Nat\u00e1lia","family":"Cruz-Martins","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Porto, Alameda Prof. Hernani Monteiro, 4200-319 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health (i3S), University of Porto, Rua Alfredo Allen, 4200-135 Porto, Portugal"}]},{"given":"Concei\u00e7\u00e3o","family":"Souto  Moura","sequence":"additional","affiliation":[{"name":"Pathology Department, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"}]},{"given":"Susana","family":"Guimar\u00e3es","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Porto, Alameda Prof. Hernani Monteiro, 4200-319 Porto, Portugal"},{"name":"Pathology Department, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"}]},{"given":"Ana","family":"Justino","sequence":"additional","affiliation":[{"name":"Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), 4200-135 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health (i3S), University of Porto, Rua Alfredo Allen, 4200-135 Porto, Portugal"}]},{"given":"Maria Jo\u00e3o","family":"Pina","sequence":"additional","affiliation":[{"name":"Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), 4200-135 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health (i3S), University of Porto, Rua Alfredo Allen, 4200-135 Porto, Portugal"}]},{"given":"Adriana","family":"Magalh\u00e3es","sequence":"additional","affiliation":[{"name":"Pulmonology Department, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1722-3249","authenticated-orcid":false,"given":"Henrique","family":"Queiroga","sequence":"additional","affiliation":[{"name":"Pulmonology Department, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"},{"name":"Faculty of Medicine, University of Porto, Alameda Prof. Hernani Monteiro, 4200-319 Porto, Portugal"}]},{"given":"Jos\u00e9 Agostinho","family":"Marques","sequence":"additional","affiliation":[{"name":"Pulmonology Department, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"},{"name":"Faculty of Medicine, University of Porto, Alameda Prof. Hernani Monteiro, 4200-319 Porto, Portugal"}]},{"given":"Jos\u00e9 Carlos","family":"Machado","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Porto, Alameda Prof. Hernani Monteiro, 4200-319 Porto, Portugal"},{"name":"Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), 4200-135 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health (i3S), University of Porto, Rua Alfredo Allen, 4200-135 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7132-4094","authenticated-orcid":false,"given":"Jos\u00e9 Lu\u00eds","family":"Costa","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Porto, Alameda Prof. Hernani Monteiro, 4200-319 Porto, Portugal"},{"name":"Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), 4200-135 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health (i3S), University of Porto, Rua Alfredo Allen, 4200-135 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6577-0063","authenticated-orcid":false,"given":"Venceslau","family":"Hespanhol","sequence":"additional","affiliation":[{"name":"Pulmonology Department, Centro Hospitalar Universit\u00e1rio de S\u00e3o Jo\u00e3o, Alameda Prof. Hern\u00e2ni Monteiro, 4200-319 Porto, Portugal"},{"name":"Faculty of Medicine, University of Porto, Alameda Prof. Hernani Monteiro, 4200-319 Porto, Portugal"},{"name":"Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), 4200-135 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health (i3S), University of Porto, Rua Alfredo Allen, 4200-135 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1998","DOI":"10.1001\/jama.2014.3741","article-title":"Using multiplexed assays of oncogenic drivers in lung cancers to select targeted drugs","volume":"311","author":"Kris","year":"2014","journal-title":"JAMA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"iv192","DOI":"10.1093\/annonc\/mdy275","article-title":"Metastatic non-small cell lung cancer: ESMO Clinical 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