Prognostic evaluation of a multi-target magnetic bead-enriched circulating tumor cell-enriched identification system...

Colorectal cancer (CRC) is the third most prevalent cancer in the world. Traditional tissue biopsy cannot provide dynamic monitoring of patients' tumors or reflect the characteristics of tumors in real time because the sampling process is invasive and accompanied by risks. Circulating tumor cells (CTCs) are considered a major cause of tumor metastasis, and investigating CTCs helps to understand the biology and vulnerability of malignant tumors during hematogenous metastasis.

We sequentially used epithelial cell adhesion molecule (EpCAM)-coated immunoliposomal magnetic beads (Ep-IMBs) and vimentin-coated immunoliposomal magnetic beads (Vi-IMBs) to capture and characterize CTCs from 110 CRC patients. We further constructed a Cox risk regression model, optimized the model composition using backward stepwise regression, and finally applied nomograms to show the effect of each variable on survival risk.

The specificity of the CTCs enrichment and identification system was 100% and the sensitivity was 79.0%. Multivariate analysis indicated total CTC number was an important predictor for bad survival, whereas American Joint Committee on Cancer (AJCC) stage, lymph node metastasis, and carcinoembryonic antigen (CEA) level were associated with prognosis, and the risk of mortality was associated with the AJCC stage of the CRC.

The CTC enrichment and identification system constructed in this research demonstrated superior accuracy. In addition, CTCs can be used as an important predictor for prognosis of patients with CRC, and the combination of other clinical predictive factors can help clinicians to better design individualized treatment regimens, which is of great clinical application value.