Circulating tumor DNA (ctDNA) are small fragments of nucleic acid that are released into the circulating system via multiple mechanisms including apoptosis and necrosis, thereby reflecting the genomic landscape of the tumor from which it was derived. Due to its short half-life, ctDNA can facilitate in tracking the tumor burden in real-time, offering a valuable minimally invasive opportunity to monitor disease in individual cancer patients. Although not yet implemented in clinical practice, ctDNA has demonstrated potential clinical applications across all stages of cancer management, including in early diagnosis, identification of targetable genetic alterations, monitoring response to treatment and detection of minimal residual disease. Indeed, several studies have shown ctDNA to predict relapse significantly earlier than conventional clinical methods, thereby holding the potential to improve patient prognosis and survival outcomes. 

In this podcast, we spoke with Jeanne Tie, MBChB, FRACP, MD, Peter MacCallum Cancer Centre, Sanjay Popat, PhD, MBBS, FRCP, The Royal Marsden NHS Foundation Trust, London, UK, Miguel Garcia-Pardo, MD, Princess Margaret Cancer Center, Toronto, Canada, and Marla Lipsyc-Sharf, MD, Dana-Farber Cancer Institute, Boston, MA, who provide an overview of the applications of ctDNA in clinical practice and the remaining challenges yet to be overcome prior to its implementation in clinical practice.