Clinical Applications of Liquid Biopsies in Gastrointestinal Oncology

Accumulating knowledge in colorectal cancer (CRC) biology has led to an understanding of the role of genetic and epigenetic alterations in tumorigenesis and progression of the disease. Numerous studies have focused on the identification of novel biomarkers in circulating free (cf)DNA that have the potential of guiding clinical practice. These markers are specifically attractive for the characterization of molecular profiles in patients with limited tissue access, the monitoring of therapeutic responses and the development of recurrent disease, the monitoring of the tumor evolution with therapy, and the response to therapy. Moreover, cfDNA can be useful for early detection and detection of minimal residual disease and to improve characterization of the pharmacodynamic effects of a drug. This review will focus on recent advances of cfDNA analysis and novel discoveries that have the potential to guide treatment of CRC.