To demonstrate that the ScreenCell® CYTO device is capable of isolating circulating tumor cells (CTCs) in metastatic breast cancer and counting these cells based on the expression of specific biomarkers. Two biomarker cocktails will be compared:
1) Conventional cocktails: EpCAM + Cytokeratin + CD45
2) ScreenCell cocktail: MARCKSL1, SLC9A3R1, and RHOD