Acute myeloid leukemia: negative prognostic impact of early blast persistence can be in part overcome by a later remission prior to post-induction therapy.

In acute myeloid leukemia (AML), there is an ongoing debate on the prognostic value of the early bone marrow (BM) assessment in patients receiving intensive therapy. In this retrospective study, we have analyzed the prognostic impact of the early response in 1008 newly diagnosed AML patients, who were treated at our institution with intensive chemotherapy followed by consolidation chemotherapy and/or allogeneic hematopoietic stem cell transplantation (allo-HSCT). We found that early blast persistence has an independent negative prognostic impact on overall survival (OS), event-free survival (EFS) and relapsefree survival (RFS). This negative prognostic impact may only be overcome in patients showing at least a partial remission at the early BM assessment and who subsequently achieve blast clearance by additional induction chemotherapy prior to consolidation therapy with allo-HSCT. In accordance, we propose that the time slope of remission is an additional leukemia-related dynamic parameter that reflects chemosensitivity and thus may inform postinduction therapy decision-making. In addition to patient-related factors, European LeukemiaNet (ELN) risk group, measurable residual disease (MRD) monitoring and donor availability, this may particularly apply to ELN intermediate risk patients, in whom a decision between consolidation chemotherapy and allo-HSCT remains challenging in many cases.