scholarly journals Clinical Application of Next-Generation Sequencing of Plasma Cell-Free DNA for Genotyping Untreated Advanced Non-Small Cell Lung Cancer

Cancers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2707
Author(s):  
Maria Gabriela O. Fernandes ◽  
Natália Cruz-Martins ◽  
Conceição Souto Moura ◽  
Susana Guimarães ◽  
Joana Pereira Reis ◽  
...  

Background: Analysis of circulating tumor DNA (ctDNA) has remarkable potential as a non-invasive lung cancer molecular diagnostic method. This prospective study addressed the clinical value of a targeted-gene amplicon-based plasma next-generation sequencing (NGS) assay to detect actionable mutations in ctDNA in patients with newly diagnosed advanced lung adenocarcinoma. Methods: ctDNA test performance and concordance with tissue NGS were determined, and the correlation between ctDNA findings, clinical features, and clinical outcomes was evaluated in 115 patients with paired plasma and tissue samples. Results: Targeted-gene NGS-based ctDNA and NGS-based tissue analysis detected 54 and 63 genomic alterations, respectively; 11 patients presented co-mutations, totalizing 66 hotspot mutations detected, 51 on both tissue and plasma, 12 exclusively on tissue, and 3 exclusively on plasma. NGS-based ctDNA revealed a diagnostic performance with 81.0% sensitivity, 95.3% specificity, 94.4% PPV, 83.6% NPV, test accuracy of 88.2%, and Cohen’s Kappa 0.764. PFS and OS assessed by both assays did not significantly differ. Detection of ctDNA alterations was statistically associated with metastatic disease (p = 0.013), extra-thoracic metastasis (p = 0.004) and the number of organs involved (p = 0.010). Conclusions: This study highlights the potential use of ctDNA for mutation detection in newly diagnosed NSCLC patients due to its high accuracy and correlation with clinical outcomes.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e20726-e20726
Author(s):  
Jia-Tao Cheng ◽  
Jin-Ji Yang ◽  
Yi-Long Wu

e20726 Background: Osimertinib is used to treat EGFR-mutant non–small-cell lung cancer (NSCLC) with acquired T790M mutation. Next-generation sequencing (NGS) is helpful to understand mechanisms of resistance to osimertinib. However, whether NGS after resistance to osimertinib has an impact on clinical outcomes of patients treated with subsequent treatments has been elusive. Methods: We retrospectively identified advanced, EGFR-mutant T790M positive NSCLC patients treated with the 2nd or further-line osimertinib from January 27th, 2015 to January 31th, 2019 at our institute. Genetic profiles and clinical outcomes were analyzed. These patients were divided into 2 groups based on NGS data after resistance to osimertinib. Progression-free survival1 (PFS1) was calculated from the start of osimertinib to progression or death. PFS2 was calculated from the start of subsequent-line treatment to progression or death. Objective response rate (ORR) of subsequent-line treatments was evaluated by RECIST1.1. Results: Among 187 patients treated with osimertinib, 66 had NGS data and 27 had no NGS data after progression. Maintained EGFR T790M was detected in 23 patients (34.8%), and loss of T790M was seen in 43 patients (65.2%). Mutations of EGFR C797S were detected in 12 patients (18.1% overall; 52.2% of those with retained T790M), 11 in cis with a maintained T790M, 1 in trans with a maintained T790M. There was no significant difference in median PFS1 between the maintained T790M group and the loss of T790M group (10.8 vs. 7.0 months, P = 0.085).The NGS group was treated with TKIs according to the results of NGS strictly (n = 36), the non-NGS group received chemotherapy or best supportive care (n = 11).There was a significant difference in median PFS2 between the NGS and non-NGS groups (5.4 vs. 2.9 months, P = 0.043). The ORR of the NGS group was significantly superior to that of the non-NGS group (16.2% vs 11.1%, P < 0.001). Conclusions: NGS after resistance to osimertinib might favor clinical outcomes of advanced EGFR-mutant NSCLC patients. Further more investigations are warranted.


2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Elton J. R. Vasconcelos ◽  
Chayan Roy ◽  
Joseph A. Geiger ◽  
Kristina M. Oney ◽  
Melody Koo ◽  
...  

Abstract Background Vector-borne diseases (VBDs) impact both human and veterinary medicine and pose special public health challenges. The main bacterial vector-borne pathogens (VBPs) of importance in veterinary medicine include Anaplasma spp., Bartonella spp., Ehrlichia spp., and Spotted Fever Group Rickettsia. Taxon-targeted PCR assays are the current gold standard for VBP diagnostics but limitations on the detection of genetically diverse organisms support a novel approach for broader detection of VBPs. We present a methodology for genetic characterization of VBPs using Next-Generation Sequencing (NGS) and computational approaches. A major advantage of NGS is the ability to detect multiple organisms present in the same clinical sample in an unsupervised (i.e. non-targeted) and semi-quantitative way. The Standard Operating Procedure (SOP) presented here combines industry-standard microbiome analysis tools with our ad-hoc bioinformatic scripts to form a complete analysis pipeline accessible to veterinary scientists and freely available for download and use at https://github.com/eltonjrv/microbiome.westernu/tree/SOP. Results We tested and validated our SOP by mimicking single, double, and triple infections in genomic canine DNA using serial dilutions of plasmids containing the entire 16 S rRNA gene sequence of (A) phagocytophilum, (B) v. berkhoffii, and E. canis. NGS with broad-range 16 S rRNA primers followed by our bioinformatics SOP was capable of detecting these pathogens in biological replicates of different dilutions. These results illustrate the ability of NGS to detect and genetically characterize multi-infections with different amounts of pathogens in a single sample. Conclusions Bloodborne microbiomics & metagenomics approaches may help expand the molecular diagnostic toolbox in veterinary and human medicine. In this paper, we present both in vitro and in silico detailed protocols that can be combined into a single workflow that may provide a significant improvement in VBP diagnostics and also facilitate future applications of microbiome research in veterinary medicine.


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