Clinical Summary

• Real-world use of molecular residual disease testing increased substantially between 2021 and 2023 in a large US claims database.
• MRD testing was most commonly used in colorectal, hematologic, and breast cancers, but extended across diverse tumor types.
• Roughly one-third of tested patients had advanced or metastatic disease, highlighting expanding clinical applications beyond adjuvant settings.

Molecular residual disease (MRD) testing is increasingly being integrated into oncology practice, according to a retrospective analysis of more than 11,000 patients from a large US claims database, which was presented at the 2026 Oncology Nursing Society (ONS) Congress. Researchers from Quest Diagnostics and Optum Health examined real-world utilization patterns of MRD testing across cancer types and disease stages.

MRD testing detects ultralow levels of circulating tumor DNA (ctDNA) to identify residual disease after treatment. Testing typically begins with a personalized baseline assay based on a patient’s tumor DNA, followed by serial blood monitoring, sometimes as often as every 4 weeks.

The analysis used de-identified administrative claims data from the Optum Labs Data Warehouse and included adults with cancer who underwent MRD testing between January 1, 2021, and May 31, 2024. Clinical characteristics were assessed during the 360 days before the first MRD test claim.

A total of 11,556 individuals were included in the study. More than half of all MRD tests (53.3%) were performed in the Southern United States. Testing spanned multiple malignancies, with colorectal cancer accounting for 29.1% of cases, followed by hematologic cancers (21.1%) and breast cancer (13%).

Utilization increased sharply over time, rising from 827 tests in 2021 to 2355 tests in 2022 and 5482 in 2023. Most testing was covered by Medicare Advantage plans (76.8%), while 23.2% of patients had commercial insurance coverage.

Although MRD testing was frequently used in earlier-stage adjuvant settings, 33.5% of evaluable patients had advanced or metastatic cancer. Investigators noted that this trend reflects expanding clinical interest in MRD applications across broader oncology populations.

The findings suggest that MRD testing is moving beyond research settings into routine clinical care for both solid and hematologic malignancies. Increasing use in metastatic disease may indicate growing interest in ctDNA monitoring for treatment response and disease surveillance.

For oncology nurses and other clinicians, the rapid adoption of MRD testing underscores the need for patient education regarding the purpose, interpretation, and potential implications of ctDNA monitoring. Because testing is now being used across diverse tumor types and disease stages, clinicians may encounter more patient questions about how MRD results influence treatment decisions and follow-up care.

The authors emphasized that “real-world evidence shows that MRD testing is rapidly increasing” and noted expanding use across “diverse solid and hematologic cancers as well as individuals with metastatic or advanced cancer.”

Overall, the study highlights the growing integration of MRD testing into contemporary cancer care and the evolving role of ctDNA-based monitoring in oncology practice.

Source:

Brassil K, Li Y, Holland E, Morin P, Stockl K, Slavin T. Real-World Utilization of Molecular Residual Disease Testing in Cancer Care. Presented at the Oncology Nursing Society Annual Congress; May 13-17, 2026. San Antonio, TX.