Single-cell omics: Circulating tumor cells

This chapter presents circulating tumor cells (CTCs) as a real-time liquid biopsy, with an emphasis on single-cell sequencing. Following an abbreviated introduction of CTC biology, a variety of the most frequently utilized CTC enrichment and detection strategies is summarized. The focus of the chapter then shifts toward single-cell CTC analysis. Methods for single CTC isolation and molecular profiling are reviewed, followed by a summary of several single CTC genomic and transcriptomic studies performed in various malignancies. The chapter closes with a discussion on the importance of single CTC molecular analysis and the unique challenges in the field.