Circulating tumor cells (CTCs) are released from primary tumors and transported through the body via blood or lymphatic vessels before settling to form micrometastases under suitable conditions. Accordingly, several studies have identified CTCs as a negative prognostic factor for survival in many types of cancer. CTCs also reflect the current heterogeneity and genetic and biological state of tumors; so, their study can provide valuable insights into tumor progression, cell senescence, and cancer dormancy. Diverse methods with differing specificity, utility, costs, and sensitivity have been developed for isolating and characterizing CTCs. Additionally, novel techniques with the potential to overcome the limitations of existing ones are being developed. This primary literature review describes the current and emerging methods for enriching, detecting, isolating, and characterizing CTCs.

Centre National de la Recherche Scientifique Institut des Neurosciences Cellulaires et Intégratives Université de Strasbourg 67000 Strasbourg France

Institute of Molecular and Translational Medicine Faculty of Medicine and Dentistry Palacky University in Olomouc 779 00 Olomouc Czech Republic

Laboratory of Experimental Medicine University Hospital in Olomouc 779 00 Olomouc Czech Republic

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