title: Prevalence of FMS-like tyrosine kinase 3/internal tandem duplication (FLT3/ITD+) in de novo acute myeloid leukemia patients categorized according to cytogenetic risk.
abstract: OBJECTIVE
  The mechanism involved in leukemogenesis remains unclear and more information about the disruption of the cell proliferation, cell differentiation and apoptosis of neoplastic cells is required.
  
  
  METHODS
  Cross-sectional prevalence study at the Discipline of Hematology, Hospital São Paulo, Universidade Federal de São Paulo.
  
  
  METHODS
  We investigated FMS-like tyrosine kinase 3/internal tandem duplication (FLT3/ITD+) in 40 adult patients with de novo acute myeloid leukemia (AML), categorized according to cytogenetic results, from September 2001 to May 2005.
  
  
  RESULTS
  Thirteen patients (32.5%) were classified as presenting the favorable karyotype, 11 patients (27.5%) as an intermediate group, 7 patients (17%) as an undefined group and 9 patients (22.5%) as the unfavorable group. FLT3/ITD+ was found in 10 patients (25%): 3 with FLT3/ITD+ and favorable karyotype; 4 with FLT3/ITD+ and intermediate karyotype; 2 with FLT3/ITD+ and undefined karyotype; and only 1 with FLT3/ITD+ and unfavorable karyotype. Among the patients without FLT3/ITD+, 10 presented favorable karyotype, 8 intermediate, 4 undefined and 8 unfavorable karyotype. The cytogenetic results showed no correlations between FLT3/ITD presence and the prognostic groups (P = 0.13). We found that 2 patients were still alive more than 24 months later, FLT3/ITD+ did not influence the patients' survival rate.
  
  
  CONCLUSIONS
  We found the same frequency of AML with FLT3/ITD+ in both the favorable and intermediate prognosis groups. Only one patient presented AML, FLT3/ITD+ and unfavorable karyotype (the hypothetical worst clinical situation). Therefore, the prognostic advantage of favorable cytogenetics among patients with FLT3/ITD+ remains to be elucidated, for it to be better understood.
authors.affiliation: Universidade Estadual de Ponta Grossa, Ponta Grossa, Paraná, Brazil.
authors.forename: Everson Augusto
authors.initials: EA
authors.lastname: Krum
authors.forename: Mihoko
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Maria de Lourdes Lopes Ferrari
authors.initials: Mde L
authors.lastname: Chauffaille
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D020440:Gene Duplication; D006801:Humans; D007621:Karyotyping; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D020080:Tandem Repeat Sequences / Q000235:genetics*; D055815:Young Adult; D051941:fms-Like Tyrosine Kinase 3 / Q000235:genetics*
chemical_list: D051941:fms-Like Tyrosine Kinase 3