The dawn of cancer genomics has ushered in an unprecedented era of precision medicine, enabling the identification of genome-wide somatic cell determinant alterations that can be used for early cancer diagnosis, prognosis, stratification into optimal therapies, and monitoring the development of resistance, as well as to predict which patients have greater chance of relapse. Currently, clinicians and translational researchers are using our greatly improved understanding of the heterogeneous molecular landscape of cancer to appropriately stratify patients into carefully selected targeted treatments with the goal of ensuring that patients receive the right treatment at the right time. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay Ultimately, there is hope that this will allow doctors to cure their patients' disease (in the early stages) or manage it for as long as possible, while still ensuring the highest possible quality of life (in the advanced stages). The current “gold standard” for diagnosing cancer and determining optimal therapeutic strategies is through surgical biopsy. However, this method has several limitations, not least that of its invasiveness. Surgical biopsies are also extremely limited as they only offer a “snapshot” in space and time of the tumor depending on the stage of the disease and local location. Furthermore, they are known to not be representative of tumor heterogeneity, resulting in a predominance of resistant clones that are refractory to therapy and ultimately disease progression/therapy resistance. Therefore, surgical biopsy cannot offer any indication of treatment efficacy and tumor evolution (especially in the metastatic setting) during a patient's therapy. In addition to this, most biopsies are stored as formalin-fixed, paraffin-embedded blocks that are used for routine pathology, requiring highly sensitive methods (such as next-generation sequencing (NGS) and digital polymerase (dPCR)) for the analysis of very limited quantities of low-quality nucleic acid. However, many of these limitations can be circumvented by using liquid biopsies. Liquid biopsy has enormous potential as a more convenient, simpler and less invasive method to diagnose and monitor cancer, as well as predict response to many currently available therapies. Liquid biopsy is used as an “umbrella” term that encompasses several analytes that can be identified in blood samples, including: circulating tumor cells (CTCs), circulating cell-free DNA (cfDNA), circulating tumor DNA (ctDNA – the cell fraction tumor-derived tumors). cfDNA), circulating RNA (including circulating microRNAs), extracellular vesicles such as exosomes, and, more recently, platelets (particularly tumor-educated platelets or TEPs) (REFs). Of these, CTC and ctDNA are currently the most validated analytes and those most likely to translate into routine clinical use within the next 2-5 years due to their proven ability to early detect cancer (REF), monitor cancer response patient to therapy (REF), predict relapse (REF), and offer actionable somatic alterations to stratify patients towards optimal therapies in real time (REFS). Overall, liquid biopsy can complement a personalized medical approach to cancer treatment.