The molecular and genetic signatures of cancer are represented in the peripheral circulation and other body fluids, giving rise to the liquid biopsy concept. This new paradigm of molecular profiling of cancer cells offers several advantages over traditional tissue biopsy. It is convenient, noninvasive, conforms to current clinical practice, enables real time disease monitoring and the study of tumor evolution, can easily be sampled multiple times, and this sample is more representative of the heterogeneous cancer cells than biopsy sampling. Indeed, all aspects of cancer molecular genetic...