detection of 11q23 gene rearrangement in children with acute lymphoblastic leukemia and its association with demographic data and response to initial chemotherapy on the seventh day of induction

background: acute lymphoblastic leukemia (all) is the most common form of childhood cancer leading to cancer-related death in children. most infants with all harbor recurring structural chromosomal rearrangements that are important initiating events in leukemogenesis but are insufficient to explain the biology and heterogeneity of the disease. mixed-lineage leukemia-rearrangement (mll-rearrangement) at 11q23 occurs in at least two-thirds of infants with all. the most common mll rearrangements are t(411)(q21q23)/mll-aff1 (af4) found in approximately 50% of patients. methods: forty children with all were enrolled in our study. 11q23 rearrangement and its association with other prognostic factors such as age, sex, initial wbc, organomegaly, immunophenotype, and therapeutic response on the seventh day of induction were studied. results: four patients including three (11.5%) boys and one (7.1%) girl were positive for 11q23 translocation. there was no association between 11q23 rearrangement and sex, age, and initial wbc counts. none of the patients with 11q23 translocation showed blast count less than 5% in the bone marrow on the seventh day of induction (p=0.002). conclusion: there was a significant correlation between 11q23 translocation with lack of initial response to chemotherapy. keywords: acute lymphoblastic leukemia, 11q23 translocation, cytogenetic, infant acute lymphoblastic leukemia, prognosis, induction failure