Minimal Residual Disease (MRD): Detecting Relapse Before It Becomes Clinically Apparent

Minimal Residual Disease (MRD) refers to the small number of cancer cells that may remain in a patient after treatment, despite achieving clinical remission by conventional assessments. These residual cells are often below the detection limits of standard imaging or histopathology, yet they can be the source of future relapse. In both hematological malignancies and an increasing number of solid tumors, MRD assessment is becoming an important extension of precision oncology.

Traditionally, post-treatment surveillance has relied heavily on imaging and clinical symptoms. While essential, these approaches often detect relapse only after a significant tumor burden has re-emerged. MRD testing, typically based on highly sensitive molecular methods, offers an earlier window into disease dynamics by identifying tumor-derived genetic material at very low levels. This molecular signal may precede radiological or clinical relapse by months.

A key strength of MRD testing lies in longitudinal monitoring. Repeated assessments over time allow clinicians to track molecular trends rather than relying on a single snapshot. Rising MRD levels can suggest impending relapse, while sustained MRD negativity may provide reassurance of durable response. This shift from episodic evaluation to continuous molecular surveillance represents a meaningful change in how treatment success and disease control are assessed.

Clinical & Operational Relevance

When applied in appropriate clinical contexts, MRD testing supports more informed post-treatment management:

• Earlier detection of relapse compared with conventional imaging in selected settings

• Risk stratification after treatment, helping differentiate patients with higher or lower relapse risk

• Longitudinal disease monitoring, enabling trend-based interpretation rather than binary results

• Support for clinical decision-making, such as intensified surveillance or therapeutic adjustment

• Reduced reliance on frequent imaging, potentially lowering patient burden and healthcare costs

MRD testing is most valuable when integrated into a clearly defined surveillance strategy, guided by disease type, treatment intent, and clinical evidence.

AGTC Genomics CancerTRACE MRD testing is approached as a clinical decision-support tool rather than a standalone result. By leveraging sensitive molecular technologies and longitudinal testing strategies, MRD assessment is designed to complement imaging and clinical evaluation. The focus is on delivering reliable, interpretable results that help clinicians monitor treatment response, anticipate relapse, and tailor follow-up strategies in a real-world oncology setting.

Closing Remarks

MRD testing shifts cancer surveillance from waiting for visible disease to detecting molecular change early. As precision oncology continues to evolve, the ability to monitor what remains—rather than what is already evident—may play an increasingly important role in guiding long-term patient care.