Circulating Free Tumor DNA (ctDNA): The Real-Time Liquid Biopsy

Abstract

It is now well established that DNA is shed or secreted into the circulation in both normal and disease states. However, the ability to exploit this knowledge for use in clinical medicine has only recently been made possible through the advent of new technologies. Currently, cell-free DNA is being developed as a “real-time liquid biopsy” biomarker to help guide clinical decisions in diverse fields such as prenatal screening, cancer, and solid organ transplantation. The ability of cell-free circulating tumor DNA to be measured quantitatively and qualitatively presents great opportunities in clinical oncology for using blood to monitor tumor burden and assess response to therapies. Here we provide a short review of historic and recent studies demonstrating the clinical potential of detecting and measuring cell-free DNA, with a specific focus on the use of circulating tumor DNA in oncology and cancer management.