Basu Discusses Tumor-Informed MRD Assays and Clinical Decision-Making

Arnab Basu, MD, MPH, FACP, assistant professor in genitourinary medical oncology at the University of Alabama in Birmingham, discusses circulating tumor DNA (ctDNA) tests with high sensitivity and specificity. He highlights a study that shows specificity is preserved across tumor types and explains the factors that contribute to this. He also covers the impact on clinical decision-making.

Basu explains that tumor-informed minimal residual disease (MRD) assays provide high specificity by sequencing the tumor and identifying unique genomic alterations. This minimizes false positives, allowing for safer treatment decisions, especially for patients with severe disease.

Transcription:

0:10 | I think the specificity is a very important clinical parameter for making a clinical decision, because if you know that a treatment has an adverse safety signal, you do not want to provide it to a patient who does not have disease. The specificity here basically means that it is hard to be a false positive on some of these DNA tests. I can say that pretty confidently about the tumor-informed MRD assays.

0:42 | The reason for that high specificity is the way the tumor-informed assays are designed by sequencing the tumor, identifying what the genomic alterations are that are specific to that tumor, and also, certain other considerations go into it like making sure it is not an actionable mutation that is going to disappear if we treat the patient. But overall, [a patient] has to have several of these alterations present before it is called a positive, so it is hard to be positive by chance, almost impossible. When you have a patient who does have that positivity, there is a high chance this patient has a severe disease. It makes it a lot more comfortable for us to give an intervention.

REFERENCE:

Patel KR, Rais-Bahrami S, Basu A. High sensitivity ctDNA assays in genitourinary malignancies: current evidence and future directions. Oncologist. 2024;29(9):731-737. doi:10.1093/oncolo/oyae198