循环肿瘤细胞（CTCs）已成为乳腺癌的一种有前景的生物标记物，能提供对疾病进展和治疗反应的见解。虽然CTCs已在早期乳腺癌中证明了预后的相关性，但仍需要更多的验证来确定最佳的截断点。在转移性乳腺癌中，使用FDA批准的CellSearch®系统检测CTCs是一种强独立的预后因素。然而，间充质CTCs和Parsortix® PC1系统作为替代检测方法表现出潜力。本章综合评述了在乳腺癌中CTCs的临床研究，强调了它们在疾病不同阶段的预后和预测价值，并提供了对CTC研究未来可能走向的见解。©2023版权归Elsevier Inc.所有。

Circulating tumor cells (CTCs) have emerged as a promising biomarker in breast cancer, offering insights into disease progression and treatment response. While CTCs have demonstrated prognostic relevance in early breast cancer, more validation is required to establish optimal cut-off points. In metastatic breast cancer, the detection of CTCs using the Food and Drug Administration-approved CellSearch® system is a strong independent prognostic factor. However, mesenchymal CTCs and the Parsortix® PC1 system show promise as alternative detection methods. This chapter offers a comprehensive review of clinical studies on CTCs in breast cancer, emphasizing their prognostic and predictive value in different stages of the disease and provides insights into potential future directions in CTC research.Copyright © 2023. Published by Elsevier Inc.