1.Blood-based diagnostics in solid tumors: an overview.- 2.Circulating tumor cells (CTCs) in primary disease: the seed for metastasis.- 3.Enumeration and molecular analysis of CTCs in metastatic disease: The breast cancer model.- 4.Epithelial-Mesenchymal Transition (EMT) and cancer stem cells (CSCs): The traveling metastasis.- 5.Detection and monitoring of circulating immune cells in solid tumors: shifting priorities.- 6.Circulating-free tumor DNA (ctDNA): the real-time liquid biopsy.- 7.CTCs and ctDNA: two tales of a complex biology.- 8.Exosome: decoding the messaging system.