Aberrant immunophenotypic expressions in childhood acute leukemias: A tertiary care hospital experience

Pediatric acute leukemias can present with aberrant immunophenotypes characterized by a different pattern of antigen expression on malignant cells, unlike the process of usual hematopoietic maturation. The objective of this study was to determine the aberrant immunophenotype expressions in newly diagnosed pediatric acute lymphoblastic and acute myeloid leukemias.

This cross-sectional study was carried out at University of Child Health Sciences, The Children's Hospital, Lahore, from October 2022 to December 2022 after IRB approval. After taking informed consent from parents/guardians, 290 children diagnosed with acute leukemia were included in the study. Peripheral blood or bone marrow samples in EDTA vial were used for flowcytometric analysis by using BD FACS Canto II flow-cytometer. The data was collected on a pre-designed proforma and analyzed by using IBM-SPSS V-23.

Among 290 cases, Acute Lymphoblastic Leukemia (ALL) constituted 221(76.2%) cases and 69(23.7%) were Acute Myeloid Leukemia (AML). Out of the total, the aberrant antigens were present in 32(11%) patients with 40 total events (18.1% immunophenotype aberrancy rate). The most common aberrant antigens were reported in B-ALL and the most common aberrant expression was of CD13 (62.5%). In AML, the most common aberrant antigen seen was CD19 (55.6%) and in T-ALL the most common were CD117 and HLA-DR (26.6%).

The most aberrant immunophenotypic markers were seen mostly in B-ALL pediatric cases followed by AML and T-ALL. Such abnormal expressions should be kept in mind while diagnosing the children with acute leukemia as they may affect the prognosis.