Fig 1: Co-expression of epithelial markers CK and EpCAM on circulating tumor cells (CTCs) of patients with NSCLC: (A) Frequency of distinct co-expression phenotypes among CTCs identified using different enrichment approaches. Any method depicts the percentage of a specific phenotype among the total number of CTCs detected by all methods. (B) Representative images of CTCs enriched by different methods: All depicted cells co-express CK+/EpCAM+, except the ISET-enriched cell which is of the CK+/EpCAM- phenotype. A CTC cluster identified by Parsortix is also depicted, expressing CK+/EpCAM+ in all except one cell, which is of the CK+/EpCAM- phenotype (arrow). Ariol microscopy system, Genetix, New Milton, UK) (400×).