Lab Med Online.  2022 Oct;12(4):235-243. 10.47429/lmo.2022.12.4.235.

Clinical Application of Circulating Tumor DNA Analysis

• Won D
• Heo J
• Kim H
• Shin S
• Lee ST

• KMID: 2538611
• DOI: http://doi.org/10.47429/lmo.2022.12.4.235

Abstract

Liquid biopsy using circulating tumor DNA helps overcome the limitations of conventional tissue testing. Non-invasive molecular profiling using circulating tumor DNA is increasingly being used to diagnose cancer, stratify risk, and select targeted treatments. By understanding the biological characteristics of circulating tumor DNA and patient factors that can affect concentrations of circulating tumor DNA as well as optimizing the techniques, the clinical utilization of circulating tumor DNA tests can be improved. It is also necessary to formulate guidelines for the administration and reporting of circulating tumor DNA tests.

Keyword

Cell-free nucleic acids; Circulating tumor DNA; Liquid biopsy

Figure

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  Fig. 1 Origin of cell-free DNA.

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  Fig. 2 Error correction using a unique molecular identifier.

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  Fig. 3 Representative patient case (ovarian cancer) showing the feasibility of ctDNA analysis. The patient underwent debulking surgery and chemotherapy after diagnosis. The increased ctDNA levels were detected four months earlier than conventional diagnostic methods, showing that ctDNA could detect cancer recurrence earlier than CA-125 and PET-CT scans. Abbreviations: VAF, variant allele frequency; PET-CT, positron emission tomography-computed tomography; CA-125, carbohydrate antigen 125; PARPi, poly (ADP-ribose) polymerase inhibitor.

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