Risk stratification in the clinical application of minimal residual disease assessment in acute myeloid leukemia.

Background: In acute myeloid leukemia (AML), further investigation is warranted to integrate measurable residual disease (MRD) with genetic characteristics for formulating a dynamic prognostic system for predicting response and selecting appropriate postremission therapeutic strategies.

Methods: The authors incorporated MRD with genetic risk classification and assessed its impact on transplantation decision making within different risk cohorts, comprising 769 patients with newly diagnosed AML across three clinical trials. Only patients who achieved complete remission (CR) within two courses of chemotherapy were selected.

Results: In the favorable-risk and intermediate-risk groups, patients who underwent transplantation according to the protocol experienced significant 3-year overall survival (OS) benefits compared with those who did not (favorable-risk group: hazard ratio [HR], 0.38; 95% confidence interval [CI], 0.20-0.73l p = .004; intermediate-risk group: HR, 0.53; 95% CI, 0.33-0.85; p = .008). In the intermediate-risk group, early detection of MRD positivity, even after the initial course of chemotherapy, was associated with a significantly elevated cumulative incidence of relapse (47.2% vs. 36.0%; p = .009) and a notable extension of OS with allogeneic hematopoietic stem cell transplantation (HR, 0.47; 95% CI, 0.28-0.79; p = .004). Conversely, patients who achieved MRD negativity at either of the two time points had comparable OS in the favorable-risk and intermediate-risk groups, regardless of whether they underwent transplant or not. In the adverse-risk group, allogeneic hematopoietic stem cell transplantation led to improvements in OS irrespective of MRD status (HR, 0.51; 95% CI, 0.38-0.69; p < .001).

Conclusions: Early clearance of MRD demonstrated significant prognostic value, particularly for patients in the favorable-risk and intermediate-risk groups. Positive MRD status after two courses of intensive chemotherapy were associated with a higher relapse rate and inferior OS, necessitating allogeneic hematopoietic stem cell transplantation.