Molecular Cytogenetics and Immunophenotypic Characterization of Childhood Acute Leukaemia Patients in Tertiary Care Center of Bangladesh – An observative study

Abstract

Background: Childhood leukemia is genetically a heterogeneous disease. Various types of cytogenetic abnormalities and immunophenotypic character are present in leukaemia which are important for risk stratification, treatment and play as significant prognostic factor. Pediatric acute leukaemia presents with varying clinical, morphological, immunological and molecular characteristics. It is very highly curable if diagnosed and treated properly. For detail typing and subtyping of acute leukemia immunophenotyping and cytogenetics are crucial. The aim of this study was to find out the genetic abnormalities and immunophenotypic characterization of childhood acute leukaemia patients in Bangladesh. Material & Methods: This was a retrospective observational study and was conducted in the Department of pediatric hemato-oncology of Combined Military Hospital, Dhaka and Ahsania Mission Cancer Hospital, Mirpur, Dhaka, Bangladesh during the period from February,2014 to March, 2022. There was total 98 cases of acute leukaemia. Results: In total 98 patients completed the study. We found that 79.59% patients were ALL and 20.41% patients were AML. Among ALL 80.64% were B cell type, 6.40% were T cell Type ; 12.82 % had TEL/AML1 or ETV6/RUNX1 t(12;21)(p13;q22), 5.13% patient had TCF3/PBX1 or E2A/PBX1 t(1;19)(q23;p13). In AML30.00% patient had PML/RARAt(15;17)(q22;q21), 10.00% patient had AML1/ETO or RUNX1/CBFA2T1 t(8;21) (q22;q22), 5.00% patient had FLT3/ ITD. In case of B-ALL highest expression of antigen was CD19 (91.64%) followed by CD10 (80.58%), HLADR (67.94%), CD22 (72.68%), CD79a (72.68%), TdT (52.14%) and CD34 (48.98%). In 44.24% cases there was co-expression of CD10 and CD19 and there was 11.6% expression of myeloid marker CD13 and 1.58% expression of T cell marker CD5. In case of T-ALL there was 100% expression of CD3. Expression of other antigen CD4, CD5, CD7, CD8, CD4/8 co-expression, TdT was 60%. There was 40% expression of CD1a and CD2. There was 20% expression of CD10, CD34 and TCRab also. In case of AML highest expression was MPO (93.75%) followed by CD33 (87.50%), CD13 (81.25%), CD117 (75%), HLADR (43.75%) and CD64 (50%). There was 6.25% aberrant expression of B-ALL marker CD19 and T-ALL marker CD3, CD4, CD5, CD7 also. Conclusion: Depending on this study we can say that except few variations distribution of immunophenotypical subtypes and genetic abnormalities of childhood acute leukaemia are almost similar to other literature published from neighboring countries.This study will serve as a guideline for future study in our country in this aspect.