BackgroundDetection of measurable residual disease detection (MRD) by flow cytometry after the first course of chemotherapy is a standard measure of early response in patients with acute myeloid leukemia (AML). Myeloid leukemia associated with Down Syndrome (ML‐DS) is a distinct form of AML. Differences in steady‐state and regenerating hematopoiesis between patients with or without DS are not well understood. This understanding is essential to accurately determine the presence of residual leukemia in patients with ML‐DS.MethodsA standardized antibody panel defined quantitative antigen expression in 115 follow‐up bone marrow (BM) aspirates from 45 patients following chemotherapy for ML‐DS or DS precursor B‐cell acute lymphoblastic leukemia (B‐ALL‐DS) with the “difference from normal (ΔN)” technique. When possible, FISH and SNP/CGH microarray studies were performed on sorted cell fractions.Results93% of BM specimens submitted post chemotherapy had a clearly identifiable CD34+CD56+ population present between 0.06% and 2.6% of total non‐erythroid cells. An overlapping CD34+HLA‐DRheterogeneous population was observed among 92% of patients at a lower frequency (0.04%–0.8% of total non‐erythroid cells). In B‐ALL‐DS patients, the same CD34+CD56+ HLA‐DRheterogeneous expression was observed. FACS‐FISH/Array studies demonstrated no residual genetic clones in the DS‐specific myeloid progenitor cells.ConclusionsNon‐malignant myeloid progenitors in the regenerating BM of patients who have undergone chemotherapy for either ML‐DS or B‐ALL‐DS express an immunophenotype that is different from normal BM of non‐DS patients. Awareness of this DS‐specific non‐malignant myeloid progenitor is essential to the interpretation of MRD by flow cytometry in patients with ML‐DS.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.