Impact of pretransplant measurable residual disease on the outcome of allogeneic hematopoietic cell transplantation in adult monosomal karyotype AML

Allogeneic hematopoietic cell transplantation (HCT) is often unsuccessful for monosomal karyotype (MK) acute myeloid leukemia (AML). To what degree failures are associated with pretransplant measurable residual disease (MRD)—a dominant adverse-risk factor—is unknown. We therefore studied 606 adults with intermediate- or adverse-risk AML in morphologic remission who underwent allogeneic HCT between 4/2006 and 1/2019. Sixty-eight (11%) patients had MK AML, the majority of whom with complex cytogenetics. Before HCT, MK AML patients more often tested MRD pos by multiparameter flow cytometry (49 vs. 18%; P