Accurate isolation and detection of circulating tumor cells using enrichment-free multiparametric high resolution imaging
Frontiers in Oncology. 2023;13:1141228. DOI 10.3389/fonc.2023.1141228. PMID 37051527. PMCID PMC10083432.
How to cite
AMA
Yeo D, Kao S, Gupta R, Wahlroos S, Bastian A, Strauss H, et al. Accurate isolation and detection of circulating tumor cells using enrichment-free multiparametric high resolution imaging. Front Oncol. 2023;13:1141228. doi:10.3389/fonc.2023.1141228APA
Yeo, D., Kao, S., Gupta, R., Wahlroos, S., Bastian, A., Strauss, H., et al. (2023). Accurate isolation and detection of circulating tumor cells using enrichment-free multiparametric high resolution imaging. Frontiers in Oncology, 13, 1141228. https://doi.org/10.3389/fonc.2023.1141228BibTeX
@article{yeo2023accurate,
title = {Accurate isolation and detection of circulating tumor cells using enrichment-free multiparametric high resolution imaging},
author = {Yeo, Dannel and Kao, Steven and Gupta, Ruta and Wahlroos, Sara and Bastian, Althea and Strauss, Heidi and others},
journal = {Frontiers in Oncology},
volume = {13},
pages = {1141228},
year = {2023},
doi = {10.3389/fonc.2023.1141228}
}Circulating tumor cells carry information about a patient's cancer, but they are vanishingly rare in blood, and most detection methods first enrich for them by size or by an epithelial surface marker. Those steps can discard the very cells that have changed shape or shed the marker being used to catch them.
This study validated an enrichment-free approach that isolates every nucleated cell by density and then images whole slides to find the rare tumor cells, testing it on healthy blood spiked with known numbers of cancer cells and on blood from four patients with pancreatic, thyroid, or small cell lung cancer.
It recovered spiked cells accurately even at five cells per tube, and the results held whether blood was processed immediately or up to three days after collection.
Key findings
- The workflow identified spiked-in cancer cells accurately, down to five cells in 7.5 mL of blood. Classifying ten five-cell spike-in samples against ten cell-free control samples gave 90% sensitivity, 100% specificity, and 95% overall accuracy.
- Density-based isolation recovered far more cells than the standard alternatives. Across spike-in levels the method recovered 90.9% of cancer cells (R² = 0.984), significantly higher than density-gradient centrifugation (20.0%, p = 0.004) or red-blood-cell lysis (52.0%, p = 0.030).
- Recovery stayed stable for up to three days after collection, with high reviewer agreement. Cell recovery showed no significant loss when blood was processed at 24 or 72 hours versus the day of draw, and two blinded reviewers scored samples concordantly (R² = 0.998 spiked-in, 0.984 clinical).
The AccuCyte–CyteFinder workflow in the methods
“AccuCyte isolation involves transferring 7.5 mL of blood to a Separation Tube and centrifuging to separate blood into the three main components: red blood cells, nucleated cell layer and plasma. A CyteSeal is applied between the red blood cell and nucleated cell layer and plasma is removed. Another centrifugation results in the capture of nucleated cells into the isolation tube. Nucleated cells are spread onto slides using the CyteSpreader device and then stained using RarePlex kits and an automated slide stainer. Slides are then scanned on the CyteFinder instrument and analyzed using the CyteMapper software to identify rare cells based on their marker expression.”
— Yeo et al., Frontiers in Oncology (2023), Methods, “CTC enumeration workflow using the AccuCyte-CyteFinder system”
Disclosure: RareCyte is listed as an author affiliation on the publication cited above.
Disclosure: RareCyte is named in the competing-interests statement of the publication cited above.
Why it matters for The AccuCyte–CyteFinder workflow users
If you are considering circulating tumor cells as a readout, the hardest part is not the counting but keeping the rare cells in view long enough to count them. The AccuCyte–CyteFinder workflow separates every nucleated cell from blood by density, then spreads the cells onto slides and images the whole surface, so no candidate is discarded before scoring. That matters because a method built around an epithelial surface marker keeps only the cells that still display it, and a tumor cell that has shifted phenotype and lost that marker is gone before it can be seen. Here the antigen-agnostic first step let the study recover spiked cells accurately down to five per tube, hold that recovery when blood sat for up to three days, and reach close agreement between two independent reviewers. For your own work the trade is explicit: you image a large nucleated-cell population rather than a pre-selected subset, and that is what makes rare, marker-variable tumor cells reliably detectable.
