EGFR and metastatic prostate carcinoma: To check if the isolated fractions represent tumoral subpopulations with differential phenotypes we performed gene expression analysis by RT-qPCR of CTCs isolated from patients with prostate metastatic cancer (n = 8; 26 ± 19.79 x 106 PBMCs) using anti-EpCAM, anti-EGFR and anti-FGFR magnetic beads.