Combination of microfluidic chips and biosensing for the enrichment of circulating tumor cells

It has been reported that more than 90% of cancer patients are died from cancer metastasis. Circulating tumor cells (CTCs) could detach from solid tumors to form new lesions via blood transport and play an important role in cancer metastasis and progression. As part of the liquid biopsy, the investigation and analysis toward CTCs are of great importance for prognosis assessment and tumor precision medical treatment. Unfortunately, the enrichment of circulating tumor cells has been a huge challenge due to the fact that CTCs are very rare and vulnerable. Thus, a number of effective strategies have been developed for the enrichment of CTCs. This paper discusses the advantages and disadvantages of label-free and label-based methods commonly used in the isolation of CTCs. In particular, we systematically review the most recent advances in the combination of microfluidic chips and biosensing for the enrichment of circulating tumor cells. Finally, we put forward the current barriers that need to be overcome and developmental trends in the CTCs research.