Chemotherapy Intensity, MRD Status, and Outcomes in AML
Posted: Wednesday, April 28, 2021
Measurable residual disease (MRD; formerly known as minimal residual disease) in patients with acute myeloid leukemia (AML) who achieved complete remission portends a poor prognosis. Randomized trials have yet to address whether treatment intensity may impact the rates of complete remission without MRD. Published in Leukemia & Lymphoma, a letter to the editor by Elihu H. Estey, MD, of the University of Washington, Seattle, and colleagues implied it might not matter how patients achieve MRD-negative remission.
“Our results suggest [the] effects of chemotherapy intensity on the outcome are mediated by different rates of MRD-negative complete remission rather than qualitative differences in the nature of the MRD-negative remissions induced by regimens of different intensities,” the investigators commented. “However, rates of MRD-negative complete remission are likely influenced by factors other than treatment intensity.”
A total of 516 patients who received high- (92%) or low- (8%) intensity therapy was enrolled in the study. The rates of MRD-negative remission were 80% and 52% in those who underwent high- and low-intensity therapy, respectively. Overall (P = .23) and relapse-free (P = .097) survival rates did not seem to differ between the treatment intensities. Patients who achieved MRD-negative remission appeared to experience better overall and relapse-free survival outcomes (P < .001 for both).
Regardless of treatment intensity, patients with MRD-negative disease seemed to have similar overall and relapse-free survival outcomes; this finding also appeared to hold true in those with MRD-positive disease. Based on the multivariate analysis, MRD status, age, performance status, and European LeukemiaNet risk seemed to be significantly associated with overall and relapse-free survival. After adjustments were made for these covariates, the intensity of therapy did not appear to impact the risk of death (P = .38) or the risk of relapse or death in remission (P = .67). The effect of MRD on overall (P = .62) and relapse-free (P = .42) survival did not seem to differ between the treatment intensities.
Disclosure: The study authors reported no conflicts of interest.