Liquid biopsy in hepatocellular carcinoma

Solid tumors release a variety of cellular components into the bloodstream that can be sampled by liquid biopsy. These blood-borne biomarkers include circulating tumor cells, exosomes, cell-free DNA, and cell-free noncoding RNA. As hepatocellular carcinoma (HCC) grows in worldwide prevalence and mortality, the application of emerging liquid biopsy technologies to HCC has been a rapidly advancing area of research. The qualitative and quantitative analysis of these biomarkers holds promise for improving the clinical care of individuals with HCC. In particular, research has focused on the role of liquid biopsy in the detection of HCC at an early and curable stage, given the major clinical need for biomarkers for this purpose. Panels of liquid biopsy biomarkers or combinations of conventional and novel assays will likely optimize sensitivity and specificity in HCC surveillance for at-risk populations. Additional applications of liquid biopsy in HCC include assessment of prognosis, monitoring treatment response and disease recurrence, and assaying underlying tumor biology. The future of liquid biopsy research will move the field from exploratory studies with heterogenous techniques to validated high-throughput molecular analyses and eventually from bench to bedside.