Colorectal carcinoma (CRC) is characterized by wide intratumor heterogeneity with general genomic instability and there is a need for improved diagnostic, prognostic, and therapeutic tools. The liquid biopsy provides a noninvasive route of sample collection for analysis of circulating tumor cells (CTCs) and genomic material, including cell-free DNA (cfDNA), as a complementary biopsy to the solid tumor tissue. The solid biopsy is critical for molecular characterization and diagnosis at the time of collection. The liquid biopsy has the advantage of longitudinal molecular characterization of the disease, which is crucial for precision medicine and patient-oriented treatment. In this review, we provide an overview of CRC and the different methodologies for the detection of CTCs and cfDNA, followed by a discussion on the potential clinical utility of the liquid biopsy in CRC patient care, and lastly, current challenges in the field.

Biomedical Centre Faculty of Medicine in Pilsen Charles University 32300 Pilsen Czech Republic

Convergent Science Institute in Cancer Michelson Center for Convergent Bioscience Dornsife College of Letters Arts and Sciences University of Southern California Los Angeles CA 90089 USA

USC Institute of Urology Catherine and Joseph Aresty Department of Urology Keck School of Medicine University of Southern California Los Angeles CA 90033 USA

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Defining A Liquid Biopsy Profile of Circulating Tumor Cells and Oncosomes in Metastatic Colorectal Cancer for Clinical Utility