Circulating Tumor Cell-Derived Organoids: Current Progress, Applications, and Future

Circulating tumor cells (CTCs) are malignant cells that detach from primary or metastatic tumors and enter the bloodstream. Organoids, as three-dimensional in vitro models, can mimic the tumor microenvironment and histopathological characteristics, thereby serving as valuable tools in tumor research. CTC-derived organoids retain tumor heterogeneity and metastatic potential, which provides a unique model for the study of metastatic cascade mechanisms, individualized drug screening, and precision therapy. However, the current research on CTC-derived organoids faces challenges, such as the scarcity of CTCs and the high technical difficulty in their isolation and enrichment, which leads to a low success rate in constructing organoid models. Moreover, most existing studies focus on a single cancer type and lack systematic integration of full-process standardization as well as cross-cancer applicability. In this paper, we review the isolation and enrichment strategies of CTC-derived organoids along with the techniques for optimizing in vitro culture systems, and discusses their potential applications. This review summarizes the existing results, analyzes the technical bottlenecks, and provides a theoretical basis for the standardized construction and application of CTC-derived organoids, while promoting their application in tumor precision medicine.