Journal of Cancer Research and Clinical Oncology

, Volume 137, Issue 8, pp 1151–1173

Circulating tumor cells: advances in detection methods, biological issues, and clinical relevance

Review

DOI: 10.1007/s00432-011-0988-y

Cite this article as:
Sun, Y., Yang, X., Zhou, J. et al. J Cancer Res Clin Oncol (2011) 137: 1151. doi:10.1007/s00432-011-0988-y

Abstract

Background

Circulating tumor cells (CTCs) have long been considered a reflection of tumor aggressiveness. Hematogenous spreading of CTCs from a primary tumor is a crucial step in the metastasis cascade, which leads ultimately to the formation of overt metastases. However, owing to the rarity of CTCs in peripheral blood, detecting these cells requires methods combined with high sensitivity and specificity, which sets tremendous challenges for the implementation of these assays into clinical routine.

Methods

Generally, CTCs detection methods are composed of the following two steps: enrichment (isolation) process (morphological and immunological techniques) and detection (identification) process (cytometric and nucleic acid techniques), which may or may not be separate from enrichment. Genetic and molecular characterization of CTCs carried out by fluorescent in situ hybridization (FISH), comparative genomic hybridization (CGH), PCR-based techniques, and biomarker immunofluorescent staining extract more information about malignant profile, metastatic potential of CTCs, and the extent to which CTCs are genetically identical to the primary tumor.

Results

Recent technical advances made it possible to detect CTCs. The efficacy of circulating tumor cell (CTC) detection among patients with solid malignancy has been investigated, which shows great potential to become a tool for real-time parameter of prognosis and serve as an early marker to assess the therapeutic response in overt cancers. Improvements in detection and characterization of CTCs will hopefully lead to refinement of clinical management of cancer patients.

Conclusion

This review addresses the majority of assays that have been published thus far, including the enrichment and detection steps and the markers used in these assays, accompanied by some biological issues of CTC and the results of clinical application harvested.

Keywords

Circulating tumor cellMetastasisClinical impactEMTCirculating cancer stem cell

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  1. 1.Key Laboratory of Carcinogenesis and Cancer Invasion (Ministry of Education), Liver Cancer Institute, Zhong Shan HospitalFudan UniversityShanghaiPeople’s Republic of China
  2. 2.Institute of Biomedical SciencesFudan UniversityShanghaiPeople’s Republic of China