Figure 1. CellSearch analysis (A) and multiplex PCR performed after isolation of CTCs with AdnaTest (B) in three exemplificative patients with metastatic colorectal cancer. The figure shows that the absence of CTC at the CellSearch analysis is consistent with lack of EpCAM expression, as visualized at the AdnaTest analysis. Conversely, the approach with the multiplex PCR allows the identification of CTC underestimated by CellSearch, through the positive expression of EGFR and CEA.