CASE REPORT OF RELAPSE ACUTE LYMPHOBLASTIC LEUKAEMIA (ALL) -A DIAGNOSTIC DILEMMA

Acute lymphoblastic leukaemia (ALL) of the B-cell lineage (B-ALL) is a malignant neoplasm identified by the accumulation of immature lymphoid progenitor cells in bone marrow and blood. Numerous chromosomal aberrations have been found to be correlated with disease, relapse and its clinical outcome. The survival and cure rate has been improved drastically with the advent of modern methods of diagnosis and availability of targeted pharmacological agents. However, the limitation is the higher incidence of relapsed disease. An 8-year old male child was diagnosed with B-ALL, the disease relapsed despite proper therapeutic regimen after reporting to the hospital. Conventional cytogenetic analysis revealed a normal male karyotype. FISH panel for B-ALL including t(9;22) BCR-ABL, t(12;21) ETV6-RUNX1, KMT2A (11q23) rearrangement and t(1;19) PBX1-E2A was performed and was positive for translocation t(12;21) ETV6-RUNX1 in 70% of the cells at the time of diagnosis. At the time of relapse, patient underwent cytogenetics workup including cytogenetics and FISH. Bone Marrow karyotyping showed a male karyotype with t(12;21) in all the metaphases studied and FISH was positive for translocation t(12;21) ETV6-RUNX1 in 90% of the cells. Also, next-generation sequencing for 57 gene panel showed a novel single nucleotide polymorphism (SNP) in the FLT3 gene in exon 24, c.2888C>T. Taken together, these genetic abnormalities may have an important contribution to a good prognosis and therapeutic efficacy post relapse in the present case study. The clinical functionality of novel SNP reported in the FLT3 gene should be further explored in relation to diagnosis and clinical outcome of a disease.