In the era of precision oncology, liquid biopsy techniques, especially the use of plasma circulating tumour DNA (ctDNA) analysis, represent a paradigm shift in the use of genomic biomarkers with considerable implications for clinical practice. Compared with tissue-based tumour DNA analysis, plasma ctDNA is more convenient to test, more readily accessible, faster to obtain and less invasive, minimizing procedure-related risks and offering the opportunity to perform serial monitoring. Additionally, genomic profiles of ctDNA have been shown to reflect tumour heterogeneity, which has important implications for the identification of resistant clones and selection of targeted therapy well before clinical and radiographic changes occur. Moreover, plasma ctDNA testing can also be applied to cancer screening, risk stratification and quantification of minimal residual disease. These features provide an unprecedented opportunity for early treatment of patients, improving the chances of treatment success.
Trial registration: ClinicalTrials.gov NCT02535351 NCT03469713 NCT03414827 NCT03091192 NCT02535351 NCT02546661 NCT03263039 NCT03385655 NCT02952534 NCT02975934 NCT03228810 NCT02826772 NCT03677414 NCT03522064.