Circulating tumor DNA for MRD detection in colorectal cancer: recent advances and clinical implications.

Circulating tumor DNA (ctDNA)-based molecular residual disease (MRD) provides a powerful approach to predict recurrence in colorectal cancer (CRC) and potentially improve survival outcomes for individuals diagnosed with CRC. Currently, there are two primary technical approaches for the detection of MRD using ctDNA: the tumor-informed assays and the tumor-agnostic assays. Multiple studies have demonstrated the role of MRD detection in CRC patients after radical therapy, including early relapse monitoring, molecular profiling, and treatment response prediction. Numerous interventional clinical trials based on ctDNA are underway to explore the value of MRD in optimizing adjuvant treatment decisions for patients with CRC. Once validated, ctDNA-MRD has the potential to impact current clinical treatment decisions. In this review, we summarize current techniques for detecting MRD based on ctDNA and review the data that have been collected to date on MRD detection in CRC patients who received curative-intent therapy. We also discuss prospective research of ctDNA MRD detection in this patient population and provide guidelines for the current and future use of MRD in clinical practice.