Clinico-haematological Profile and Post-Induction Remission Status of Newly Diagnosed Paediatric Acute Lymphoblastic Leukaemia Patients with ETV6::RUNX1 Gene Rearrangement

Abstract

Objectives: To determine the frequency of ETV6:RUNX1 gene rearrangement in paediatric acute lymphoblastic leukaemia in Pakistan and to determine the clinico-haematological profile and post induction remission status of newly diagnosed paediatric acute lymphoblastic leukaemia and compare them across gender and based on ETV6::RUNX1 gene rearrangement positivity.

Methodology: This descriptive cross-sectional study was conducted at Department of Haematology, Armed Forces Institute of Pathology, Rawalpindi, Oct 2021 to Aug 2023. The study sample was composed of 229 cases of paediatric acute B-cell lymphoblastic leukaemia. Patients who had B-ALL occurring as a second malignancy, Down’s syndrome, those who had received chemotherapy or corticosteroids were excluded. Patients ETV6:RUNX1 gene rearrangement status was determined by PCR. All patients underwent induction with the UK ALL 2019 protocol. Bone marrow aspiration and trephine was conducted on Day+29 of induction to assess remission and MRD status.

Results: Our study sample had a median age of 3.0 (IQR: 4.0) years, 136 (59.4%) were male. ETV6::RUNX1 gene rearrangement was seen in 36 (15.7%) cases. There were no statistical differences with regards to clinico-haematological profile at presentation and outcomes between genders and among patients with and without ETV6:RUNX1 gene rearrangement, except for MRD which had a higher frequency of being negative in the former, (p=0.023).

Conclusion: ETV6::RUNX1 rearrangement is associated with a higher frequency of negative MRD post-induction.