Table 1 Comparison of current CTC enrichment and detection method with CTCscope technique
From: Application of circulating tumor cells scope technique on circulating tumor cell research
Method | Enrichment | Detection | Sensitivity | Specificity | Sample volume | Cell morphology | Cell viability | Limitations | Advantages | Reference |
|---|---|---|---|---|---|---|---|---|---|---|
CTCscope | Density of mononuclear cells (Ficoll centrifugation) | RNA ISH (Multiplex CTC specific mRNA) | High | High | Less blood sample | Good | Live cells | Not easy to perform in a clinical lab | Simple technique; EpCAM-negative cells can be isolated | Payne et al. 2012 [4] |
CellSearch | Immunomagnetic enrichment of EpCAM-positive cells | IHC (CKs, CD45, DAPI) | Moderate; low in EpCAM negative cases | High | At least 7.5 mL blood sample | Poor | Live or dead cells | Cannot identify EpCAM-negative CTCs (such as tumour stem cells with estrogen receptor negative phenotype in breast cancers); expensive; | Easy to use semiautomated system; reproducibility; only assay approved by FDA | Peeters et al. 2013 [5] |
AdnaTest | Detected only viable CK19-releasing | RNA isolation and multiplex PCR for tumour-specific transcripts (MUC1+/HER2+/EpCAM+) | High | High | 5mL | Good | - | MUC1 is also expressed on activated T lymphocytes; Semiquantitative PCR | Enables the additional analysis of transcripts | Tewes et al. 2009 [6] |
MagSweeper | Magnetic isolation | None | High | High | At least 7.5 mL blood sample | Good | Live cells | Low efficiency | No impact on the transcriptional profile of single cancer cell isolated | Talasaz et al. 2009 [7] |
Cytometric analysis | Immunoflurorescent detection of antigen expression | None | Low | - | - | Good | Live cells | Dependent on expression of epithelial or tumor markers | Further characterization (FACS); multiple antibodies; morphology evaluation | Lu et al. 2010 [8] |