Circulating Tumor Cells: State-of-the-art Update on Technologies and Clinical Applications
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Purpose of Review
Circulating tumor cells represent rare events in the peripheral blood of patients with cancer that can provide insight into tumor biology. CTC enumeration, isolation, and analysis represent liquid biopsy approaches whose role in the management of patients with cancer continues to evolve in the era of precision medicine. This review presents an overview of technologies central to studying CTCs.
Technologies for CTC isolation can be divided into two categories: label-dependent and label-independent. Label-dependent techniques utilize biological properties such as cell surface proteins, while label-independent techniques utilize distinctive physical properties such as cell size, density, and plasticity. Advances in microfluidics designs as well as hybrid combinations of label-dependent and label-independent techniques have resulted in unprecedented improvements in CTC isolation, permitting not only the detection and enumeration of these rare events but also providing the means for studying them and exploring them as a new dimension of cancer biomarkers.
With advances in tools for isolating and studying CTCs in hand, questions regarding the clinical utility of CTC enumeration in peripheral blood, detection of CTC-associated biomarkers, and analysis of dynamic changes in CTCs during the course of cancer therapy represent exciting new opportunities for cancer research.
KeywordsCirculating tumor cells Biomarker Cancer
Compliance with Ethical Standards
Conflict of Interest
Kristofor Yap declares no conflict of interest. Evan Cohen reports grants from ANGLE, Plc. and Hitachi Chemical. James M. Reuben has received research funding from and is a member of the Scientific Advisory Board of ANGLE, Plc. He also reports grants and personal fees from Hitachi Chemical Company. Joseph D. Khoury has received research funding from and is a member of the Scientific Advisory Board of ANGLE, Plc.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: •• Of major importance
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