Liquid biopsy in colorectal cancer

Abstract

Colorectal cancer is a major health problem worldwide. When detected in time, colorectal cancer usually can be cured by surgical excision. Unfortunately, when diagnosed at late stages, the prognosis remains hapless. Tumor heterogeneity is difficult to quantify in traditional biopsies, as well as detect genomic resistance to treatment. To overcome these issues, new approaches that include circulating tumor cells and circulating tumor DNA detection in plasma are under investigation to elucidate their use as a surrogate for tumor biopsy. Several studies situate “liquid biopsy” as a potential serum biomarker for screening and diagnosis of colorectal cancer. Its prognostic and predictive competence has been explored. Published results support liquid biopsy as a reliable marker of survival and its usefulness for monitoring tumor resistance to treatment. In addition to circulating tumor cells and circulating tumor DNA, circulating exosomes might become promising candidates as novel biomarkers. Future assays should focus on interventional studies to demonstrate the clinical utility of liquid biopsy.