Frequency of 11 q23/MLL gene rearrangement in Egyptian childhood acute myeloblastic leukemia: biologic and prognostic significance

ABSTRACT

Molecular cytogenetic abnormalities involving 11q23 are among the most cytogenetic abnormalities in AML patients. We aimed to evaluate the frequency of MLUAF9 fusion gene in AML patients and its prognostic significance. Twenty eight children patients with AML and twenty healthy controls were subjected to complete clinical examination and laboratory investigations including, complete hemogram and BM examination. Diagnosis was. based on FAB morphologic and immunophenotypic criteria. Detection of [MLUAF9] fusion gene were assessed by dual color FISH. Follow up were carried out clinically and by blast count in BM, and response to therapy to detect the outcome of the disease. The frequency of MLL fusion gene MLUAF9 in AML cases was 21% [6/28]. Four patients with MLUAF9 fusion gene were newly diagnosed, two cases were at relapse and no patient at remission showed positivity. As regard the clinical outcome, five out of six MLL positive cases died, three of them during induction and two during relapse. The FAB AML subtypes with MLUAF9 fusion were one M2, three M4 and two M5. FISH technique is a sensitive tool for rapid detection of MLL gene rearrangement at diagnosis which is of high clinical relevance directing treatment strategy as most of these abnormalities have been associated with poor prognosis