Current Colorectal Cancer Reports

, Volume 12, Issue 3, pp 151–161 | Cite as

Circulating Tumor Cells Versus Circulating Tumor DNA in Colorectal Cancer: Pros and Cons

  • Carlyn Rose C. Tan
  • Lanlan Zhou
  • Wafik S. El-DeiryEmail author
Translational Colorectal Oncology (Y Jiang, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Translational Colorectal Oncology


Circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) are emerging noninvasive multifunctional biomarkers in liquid biopsy allowing for early diagnosis, accurate prognosis, therapeutic target selection, spatiotemporal monitoring of metastasis, as well as monitoring response and resistance to treatment. CTCs and ctDNA are released from different tumor types at different stages and contribute complementary information for clinical decision. Although big strides have been taken in technology development for detection, isolation and characterization of CTCs and sensitive and specific detection of ctDNA, CTC-, and ctDNA-based liquid biopsies may not be widely adopted for routine cancer patient care until the suitability, accuracy, and reliability of these tests are validated and more standardized protocols are corroborated in large, independent, prospectively designed trials. This review covers CTC- and ctDNA-related technologies and their application in colorectal cancer. The promise of CTC- and ctDNA-based liquid biopsies is envisioned.


Circulating tumor cells (CTCs) Circulating tumor DNA (ctDNA) Colorectal cancer (CRC) Liquid biopsy Tumor heterogeneity CTC enrichment Positive selection Negative selection Precision medicine Resistance mechanism 


Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

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.


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Carlyn Rose C. Tan
    • 1
  • Lanlan Zhou
    • 1
  • Wafik S. El-Deiry
    • 1
    Email author
  1. 1.Department of Hematology/Oncology and Molecular Therapeutics ProgramFox Chase Cancer CenterPhiladelphiaUSA

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