Deciphering the Significance of CD56 Expression in Pediatric Acute Myeloid Leukemia: A Report from the Children's Oncology Group

• Published in: Cytometry. Part B, Clinical cytometry Vol. 98; no. 1; pp. 52 - 56
• Main Authors: Pardo, Laura M., Voigt, Andrew P., Alonzo, Todd A., Wilson, Elisabeth R., Gerbing, Robert B., Paine, Dana J., Dai, Fangyan, Menssen, Andrew J., Raimondi, Susana C., Hirsch, Betsy A., Gamis, Alan S., Meshinchi, Soheil, Wells, Denise A., Brodersen, Lisa Eidenschink, Loken, Michael R.
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.01.2020; Wiley Subscription Services, Inc
• Subjects: Acute myeloid leukemia; AML; Antigens; Bone marrow; CD56; CD56 antigen; Children; Children & youth; Cluster analysis; Clustering; Cytometry; Flow cytometry; Fluorescence; Genotypes; Leukemia; Medical prognosis; multidimensional immunophenotype; Myeloid leukemia; Oncology; Patients; pediatric; Pediatrics; Phenotypes; Principal components analysis; Surface antigens; Transcription; AML; flow cytometry; CD56; multidimensional immunophenotype; pediatric
• ISSN: 1552-4949; 1552-4957
• DOI: 10.1002/cyto.b.21829

Background In patients with acute myeloid leukemia (AML), CD56 expression has been associated with adverse clinical outcome. We reported on a phenotype associated with very poor prognosis (RAM) in children enrolled in the Children's Oncology Group trial AAML0531 (Brodersen et al. Leukemia 30 (2016) 2077–2080). RAM is also characterized in part by high‐intensity expression of the CD56 antigen. Herein, we investigate underlying biological and clinical differences among CD56‐positive AMLs for patients in AAML0531. Methods For 769 newly diagnosed pediatric patients with de novo AML enrolled in AAML0531, bone marrow specimens were submitted for flow cytometric analysis. For each patient, an immunophenotypic expression profile (IEP) was defined by mean fluorescent intensities of assayed surface antigens. Unsupervised hierarchical clustering analysis (HCA) was completed to group patients with similar immunophenotypes. Clusters were then evaluated for CD56 expression. Principal component analysis (PCA) was subsequently applied to determine whether CD56‐positive patient groups were nonoverlapping. Results HCA of IEPs revealed three unique phenotypic clusters of patients with CD56‐positive AML, and PCA showed that these three cohorts are distinct. Cohort 1 (N = 77) showed a prevalence of t(8;21) patients (72%), Cohort 2 (N = 52) a prevalence of 11q23 patients (69%), and Cohort 3 (RAM) (N = 16) a prevalence of patients with co‐occurrence of the CBFA2T3–GLIS2 fusion transcript (63%). The 5‐year event‐free survival (EFS) for Cohorts 1, 2, and 3 were 69, 39, and 19%, respectively. Conclusions When leukemia is considered by its multidimensional immunophenotype and not by the expression of a single antigen, correlations are seen between genotype and there are significant differences in patient outcomes. © 2019 International Clinical Cytometry Society