Abstract B28: Large and polymorphonuclear circulating cancer-associated cell with dual epithelial and macrophage/myeloid phenotype as a liquid biomarker in non-small cell lung cancer patients

Purpose: In addition to the FDA-approved definition of a circulating tumor cell (CTC), various phenotypes of circulating cancer-associated cells in the blood have been described. A distinct large (>30μm), polymorphonuclear, circulating, cancer-associated cell (CCAC) with a dual epithelial and macrophage/myeloid phenotype has been identified in solid cancer patients. The goal of the study was to identify and further characterize these hybrid CCACs in non-small cell lung cancer (NSCLC) patients. Experimental Design: In a prospective trial, 7.5 mL of peripheral blood was collected from 167 subjects. CTCs and CCACs were isolated by size-based exclusion with a microfilter and immunofluorescence staining was performed (cytokeratin (CK) 8/18/19, EpCAM, CD14/45, DAPI). Results: 78 NSCLC patients and 89 control subjects (69 chronic smokers with and without lung nodules on screening LDCT, 20 healthy never-smokers) were enrolled. Distinct, large, polymorphonuclear CKpos/EpCAMpos/CD14/45pos CCACs were detected at lower rates than traditional CKpos/EpCAMpos/CD45negCTCs, but significantly higher in subjects with NSCLC in comparison to controls (p