Feasibility of whole-exome sequencing of circulating tumor cells

The objective of our study was to evaluate the feasibility of whole-exome sequencing in circulating tumor cells (CTCs) and corresponding formalin-fixed, paraffin-embedded (FFPE) tumor tissue from metastatic breast cancer patients. The goal is to determine and compare the gene mutations, copy number alterations and structural variants in the coding sequences in CTCs and FFPE tumor tissue in order to elucidate if CTCs genomic alterations are clinically useful biomarkers. With this approach, we seek to establish the potential clinical utility of detailed molecular characterization of CTCs. Cancer cells may acquire resistance to therapy through molecular and genetic alterations. A detailed characterization of CTCs could provide useful clues about the mechanisms and gene mutations that lead to treatment resistance. Ultimately, this information holds enormous potential to be used as predictive biomarkers to guide clinicians in therapeutic decisions and be of great benefit to breast cancer patients.