Blood circulating tumor DNA for non-invasive genotyping of colon cancer patients

Most solid tumors, including colorectal cancers, shed cell-free DNA (ctDNA) in the blood. ctDNA can be analyzed to generate molecular profiles which capture the heterogeneity of the disease more comprehensively then tumor tissue biopsies. This approach commonly called ‘liquid biopsy’ can be applied to monitor response to therapy, to assess minimal residual disease and to uncover the emergence of drug resistance. This review will discuss current and future developments of ctDNA analysis in the clinical management of colorectal cancer patients. •Liquid biopsies can be used to define – non invasively-the molecular profiles of the disease.•ctDNA analysis can be used to assess minimal residual disease and to monitor response and resistance to therapy.•Liquid, as compared to tissue biopsies, capture more comprehensively the molecular heterogeneity of colorectal cancers.•Radiological measurements and ctDNA assessments can be successfully combined to tailor treatments.•Large prospective studies are needed to incorporate liquid biopsies in the management of colorectal cancer patients.