Immunophenotypic Aberrancies in Acute Lymphoblastic Leukaemia: A Crosssectional Study from a Tertiary Care Centre in Rajasthan, India

Introduction: Leukaemic cells display characteristic patterns of surface antigenic expression. Aberrant phenotypes are defined as patterns of antigen expression on neoplastic cells that deviate from the process of normal haematopoietic maturation. Flow cytometric immunophenotyping in acute leukaemia is an important tool for the detection of these aberrancies. Aim: The present study aimed to access immunophenotypic aberrancies in B and T Acute Lymphoblastic Leukaemia (ALL). Materials and Methods: This prospective cross-sectional study included 137 newly diagnosed ALL (B and T lineage) patients from June 2023 to November 2024 at Mahatma Gandhi Medical College and Hospital, Jaipur, Rajasthan, India. Haematological parameters, including mean haemoglobin levels, Total Leukocyte Count (TLC), platelet count, and blast percentage were analysed using a cell counter and peripheral blood and bone marrow examination. Flow cytometric analysis was performed using the Beckman Coulter DxFLEX 13-colour flow cytometer. Cytogenetic studies were carried out using conventional G-banding karyotyping. Statistical analysis was conducted using the Statistical Package for Social Sciences (SPSS) statistics software windows version 22.0 released 2013. Statistical tests like Pearson’s Chi-square test and MannWhitney Test were applied. Results: Out of 137 cases of ALL; B-ALL comprised 114 (83.2%) cases and T-ALL 23 (16.7%) cases. For B-ALL, the mean age was 23.9±20.05 years whereas T-ALL subjects had a mean age of 25.3±20.88 years. The proportional frequency of aberrant antigen expression in B-ALL and T-ALL was 53 (46.50%) and 7 (30.4%), respectively. The most common aberrant antigen in B-ALL was CD33 and in T-ALL was CD13. No significant association between haematological parameters and cytogenetic abnormalities in cases with conventional and aberrant phenotype. Conclusion: B-ALL showed greater antigen heterogeneity than T-ALL. Aberrant markers may aid in residual disease monitoring, indicate genetic events, predict prognosis, and serve as therapeutic targets.