Liquid biopsy is an approach to detect cancer using circulatory biomarkers in body fluids such as blood, urine, oral mucosa, and cerebrospinal fluid. Due to its minimally invasive and repeatable capabilities, liquid biopsy has received tremendous attention and significant clinical implications in diagnosis and prognosis. Enormous progress has been made in the development of liquid biopsy-based methods. The last five years saw a staggering 800% increase in number of scientific articles about liquid biopsy. 

Liquid biopsy has emerged as a promising avenue for cancer screening. Circulatory biomarkers such as circulating tumor DNA, circulating tumor cells (CTC), circulating microRNAs, hold promise for cancer monitoring and diagnosis.