Fig. 3From: PD-L1 expressing circulating tumour cells in head and neck cancersSingle CTCs detected after enrichment using spiral microfluidics. Immunofluorescent staining for (a) DAPI (b) Cytokeratin (c) EGFR (d) Composite EGFR/DAPI (e) CD45. CTCs: EGFR + CK + DAPI + CD45-. White blood cells: CD45 + DAPI+. Scale bar represents 50 μmBack to article page