Aberrant immunophenotypic expressions in acute lymphoid leukemia: an observational analytical study

Abstract

Background: This study aims to find out the expression of aberrant immunophenotypic markers in acute lymphoid leukemia (ALL) and to co-relate its expression with cytogenetic and molecular data.Methods: Retrospective cum prospective study was carried out in 75 patients of ALL who presented to Apollo Gleneagles hospitals, Kolkata from January 2014 and March 2019. Flow cytometry analysis was done using FC500 (Beckman coulter) All cases were classified according to latest WHO classification.Results: Out of 75 cases of ALL, 23 cases (30.67%) showed aberrant cross-lineage expression. Amongst the B-ALL cases, the most common aberrant antigen expressed were myeloid antigens 17 cases (77.27%). Aberrant T- antigens were noted in 4 cases (18.10%). Aberrant co-positivity of myeloid as well as T-antigens was seen in 1 case (4.54%). The most common aberrant myeloid antigen expressed was CD33 (77.7%) followed by CD13 (22.2%) and then CD15 (11.1%). Co-positivity of CD13 and CD33 was noted in 2 cases. CD2 and CD33 co-positivity was noted in 1 case. The most frequently expressed aberrant T-antigen was CD2 seen in 3 out of 5 cases (60%).Conclusions: In B-ALL, the most common aberration was myeloid antigen positivity followed by cross-lineage T-antigen expression. Aberrant CD33 expression was most frequently associated with t(9;22) followed by t(12;21). Aberrant CD15 was most frequently associated with t(4;11). No association with adverse hematological parameters or any significant increase in cytogenetic and molecular abnormality was noted in cases expressing aberrant antigen in comparison to cases not expressing aberrant antigens.

Hematological, clinical, immunophenotypic characterization, and treatment outcomes of prognostically significant genetic subtypes of B‐lineage acute lymphoblastic leukemia: A report of 1021 patients from India

“…Overall, we observed the expression of CD13 in 21.8% of the B‐ALL patients, CD33 in 19.7% of the B‐ALL patients, and CD117 in 4.7% of the B‐ALL patients. The authors from high‐income and low‐income countries reported the aberrant expression of myeloid marker expression including 10.5%–54.5% CD13, 2.6%–89% CD33, and 0%–26.2% CD117 38,39,60,62–75 . These differences in frequencies of expression of various myeloid markers might be attributed to the inherent genetic differences among ethnic subpopulations, technical factors such as lack of uniformity in using monoclonal antibody clone type, and differences in flow cytometry methodology, processing, and data analysis 74,76 .…”