title: Frequency of 11q23/MLL gene rearrangement in Egyptian childhood acute myeloblastic leukemia: Biologic and clinical significance.
abstract: BACKGROUND
  Molecular cytogenetic abnormalities involving 11q23 are among the most common cytogenetic abnormalities in acute myeloid leukemia (AML) patients.
  
  
  OBJECTIVE
  we aimed to evaluate the frequency of MLL/AF9 fusion gene in de novo AML patients, its impact on clinical features, and its prognostic significance.
  
  
  METHODS
  Twenty-eight children patients with AML and 20 healthy controls were subjected to complete clinical examination and laboratory investigations including, complete hemogram and bone marrow (BM) examination. Diagnosis was based on FAB morphologic and immunophenotypic criteria. Detection of (MLL/AF9) fusion gene was assessed by dual color fluorescent in situ hybridization (FISH). Follow-up were carried out clinically and by blast count in BM, and response to therapy to detect the outcome of the disease.
  
  
  RESULTS
  The incidence of MLL-fusion gene MLL/AF9 in AML cases was about (6/28) (21%). Four patients with MLL/AF9 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 MLL/AF9 fusion were one M2, three M4, and two M5.
  
  
  CONCLUSIONS
  MLL-fusion gene MLL/AF9 was found in about 21% of studied AML patients when assessed by FISH technique and this is of high clinical relevance as most of these abnormalities have been associated with poor prognosis.
authors.affiliation: Department of Pediatrics, Pediatric Hematology-Oncology Unit, Egypt.
authors.forename: Adel Abdelhaleim
authors.initials: AA
authors.lastname: Hagag
authors.affiliation: Department of Pediatrics, Pediatric Hematology-Oncology Unit, Egypt.
authors.forename: Shebl S
authors.initials: SS
authors.lastname: Shebl
authors.affiliation: Department of Clinical Pathology, Tanta University, Egypt.
authors.forename: Nabih H
authors.initials: NH
authors.lastname: El-Fadaly
keywords: 11q23/MLL gene; Acute myelobastic leukemia; Dual color FISH