The presence of minimal residual disease (MRD) is associated with poorer outcomes in patients with acute myeloid leukemia (AML) treated with traditional cytarabine- and anthracycline-based regimens. Researchers sought to understand whether the same dynamic exists for patients treated with hypomethylating agents.
In this study, 116 patients with AML treated with single-agent azacytidine, decitabine, or guadecitabine had MRD analysis performed on bone marrow specimens. The median age was 76 years. Sixty-nine (59%) patients achieved complete remission (CR) or CR with incomplete recovery of platelets or blood counts. The median number of cycles to achieve response was 2 (range, 1-6). Sixty-one patients (53%) had evaluable MRD data at the time of response, of whom 25 (41%) became MRD-negative at 3 months cumulative after CR.
MRD-negative status was associated with a reduced cumulative risk of relapse (P = 0.012) but not improved relapse-free survival (RFS) or overall survival (OS). The researchers concluded that this was due to a high frequency of nonrelapse deaths attributable to comorbidities and infections in the MRD-negative group. Likewise, patients who achieved MRD-negative status at CR and at any time up to 3 months postresponse were not associated with improved RFS or OS despite a significantly lower cumulative risk of relapse (P = 0.05).
In this group of older patients with AML treated with hypomethylating agents, achieving an MRD-negative state was associated with a reduced risk of relapse but not improved RFS or OS. Further research on patients experiencing a lower rate of nonrelapse mortality may be required to assess the true impact of MRD-negative status on survival.
Boddu P, et al. ASCO Abstract 7018.