The emerging role of circulating tumor cells in cancer management

Circulating tumor cells (CTCs) are cells that are shed from the primary tumor and circulate in the blood, and their metastasis and formation of a secondary tumor are closely associated with cancer-related death. Therefore, regulating tumor metastasis through CTCs can be a novel strategy to fight cancer. It has been demonstrated that CTCs can reflect the profile of the primary tumor and provide valuable information about intratumoral heterogeneity and their evolution over time. Moreover, the revelation of the relationship between metastasis and CTCs suggests that CTC regulation represents a promising novel anticancer strategy. Above all, at the molecular level, genetic analysis might be vital in the new era of gene-targeted cancer therapies and contribute to personalized anti-metastasis tumor treatments. In this review, we will focus on the biological significance of CTCs in the peripheral blood and discuss their potential clinical implications in cancer management.