  Immunoaffinity-based liquid biopsies of circulating tumor cells (CTCs) hold
great promise for cancer management, but typically suffer from low throughput,
relative complexity and post-processing limitations. Here we address these
issues simultaneously by decoupling and independently optimizing the nano-,
micro- and macro-scales of an enrichment device that is simple to fabricate and
operate. Unlike other affinity-based devices, our scalable mesh approach
enables optimum capture conditions at any flow rate, as demonstrated with
constant capture efficiencies, above 75% between 50-200 uL/min. The device
achieved 96% sensitivity and 100% specificity when used to detect CTCs in the
blood of 79 cancer patients and 20 healthy controls. We demonstrate its post
processing capacity with the identification of potential responders to immune
checkpoint inhibition therapy and the detection of HER2 positive breast cancer.
The results compare well with other assays, including clinical standards. This
suggests that our approach, which overcomes major limitations associated with
affinity-based liquid biopsies, could help improve cancer management.
