Abstract
Circulating tumor cells (CTCs) are shed from the primary tumor into the peripheral bloodstream, where they play crucial roles in tumor metastasis and recurrence. As a cornerstone of liquid biopsy, CTCs hold significant potential for early tumor diagnosis, therapeutic response monitoring, and prognosis. However, the rarity and heterogeneity of CTCs pose considerable challenges for their isolation and enrichment. Additionally, their predictive usefulness in tumor immunotherapy remains relatively limited. The present review summarizes recent advancements in CTC isolation and detection technologies, explores their clinical applications in immunotherapy, and discusses current challenges alongside potential strategies for improvement. The integration of these technologies into clinical practice could pave the way for more personalized and precise cancer treatment strategies in the future.