Liquid biopsy for monitoring minimal residual disease in colorectal cancer: A promising approach with clinical implications

Colorectal cancer (CRC) is a global health concern, ranking among the leading causes of cancer-related mortality. This review critically evaluates the role of liquid biopsy in detecting minimal residual disease (MRD) in CRC. The increasing incidence, particularly in China, highlights the urgency of innovative approaches for early prediction of recurrence and metastasis. The importance of MRD should be underscored as residual tumor cells post-treatment significantly impact patient prognosis. Liquid biopsy methods, including circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), exosomes, and circulating tumor RNA, are dissected for their potential in identifying molecular markers associated with CRC. The focus on ctDNA highlights its non-invasive nature, real-time monitoring capabilities, and superiority over traditional detection methods in terms of sensitivity and timeliness. The review also delves into the limitations, such as clonal hematopoiesis and the critical consideration of optimal timing for postoperative ctDNA detection. In conclusion, the review highlights the significant potential of liquid biopsy, particularly ctDNA, as a dynamic and non-invasive tool for MRD detection in CRC. By complementing traditional methods, liquid biopsy contributes to precision in tumor research and personalized treatment. These advancements offer promising avenues for improving CRC patient prognosis and tailoring individualized treatment strategies.