Characterization and identification of specific EGFR mutations in circulating tumor cells (CTCs) isolated from non-small cell lung cancer patients using antibody independent method, ApoStream.

11044 Background: A variety of methods for isolation of CTCs of epithelial origin are available; most employ antibodies to epithelial cell adhesion molecule (EpCAM). Using classic phenotypic definition, a CTC is nucleated, cytokeratin CK(+), CD45(-) cell. However, some CTCs may elude capture as they originate from primary tumor cells which have undergone epithelial-mesenchymal transition (EMT). We report here the use of ApoStream, a novel dielectrophoresis field-flow-assisted, antibody-free method to isolate CTCs from blood. Methods: Blood was collected from consented NSCLC patients and processed using ApoStrea. For CTC enumeration comparison, CellSearch FDA-approved kit was used. Isolated cells were evaluated with multiplexed immunofluorescent assay and laser scanning cytometry analysis were applied to identify multiple combinations of positive and/or negative staining for CK/CD45/DAPI and EpCam. To determine specific EGFR mutations from captured CTCs, samples were analyzed using Improved and Complete En...