Minimal Residual Disease Testing in CLL: Is It Ready for Prime Time?
Posted: Tuesday, October 19, 2021
According to Jennifer A. Woyach, MD, Associate Professor of Medicine, The Ohio State University Comprehensive Cancer Center – James Cancer Hospital and Solove Research Institute, Columbus, assessment of minimal residual disease (MRD; defined as less than 1 chronic lymphocytic leukemia [CLL] cell per 10,000 leukocytes) may help to determine prognosis after treatment with fixed-duration regimens. Data evaluating MRD assessment in both CLL and small lymphocytic lymphoma (SLL), as well as the methods and appropriate scenarios for the use of MRD testing, were discussed in detail in her presentation during the NCCN 2021 Virtual Congress: Hematologic Malignancies. At this time, she noted, it is still unclear whether MRD is helpful in guiding treatment decisions.
Flow cytometry and next-generation sequencing have demonstrated high sensitivity in MRD detection in CLL; next-generation sequencing is approved by the U.S. Food and Drug Administration. Real-time quantitative polymerase chain reaction with allele-specific oligonucleotide primers of immunoglobin heavy chain genes is a sensitive measure; however, according to Dr. Woyach, it is not used clinically in CLL at this time.
“It is clear that undetectable MRD predicts progression-free survival for patients who are treated with chemoimmunotherapy, as well as those who are treated with venetoclax plus anti-CD20 antibodies,” Dr. Woyach remarked. “Serial measurements of MRD following therapy reliably predict [disease] progression events, though with a delay.” She explained that the level of sensitivity needed for the detection of MRD is still being considered in this population. In the short term, MRD status does not seem to inform prognosis in patients treated with Bruton’s tyrosine kinase inhibitor plus venetoclax-based regimens; however, long-term data will be needed to determine whether it is beneficial.
Numerous trials have demonstrated that MRD may be used to guide therapy. It is unclear whether using an MRD-guided treatment strategy is better than using fixed-duration therapy; ongoing and future studies are warranted to clarify this clinical question.
Disclosure: For full disclosure of study authors, nccn.org.