title: Immunophenotypic characterization of acute leukemia at a public oncology reference center in Maranhão, northeastern Brazil.
abstract: OBJECTIVE
  The incidence of acute leukemia (AL) subtypes varies according to geographical distribution. The aim here was to determine the incidence of morphological and immunophenotypic AL subtypes in the state of Maranhão, Brazil, and to correlate the expression of aberrant phenotypes in children with acute lymphoblastic leukemia (ALL) with prognostic factors.
  
  
  METHODS
  Single prospective cohort study at a public oncology reference center in Maranhão.
  
  
  METHODS
  Seventy AL cases were diagnosed between September 2008 and January 2010. For the diagnosis, complete blood cell counts, myelograms (at diagnosis and at the end of the induction phase), cytochemical analysis and immunophenotyping were performed.
  
  
  RESULTS
  Among adult patients (n = 22), the incidence of AL types was: ALL (22.7%) and acute myeloid leukemia (AML) (77.3%). The subtype AML M0 occurred most frequently (29.4%). In children (n = 48), the types were: AML (18.7%), most frequently subtype AML M4 (33.4%); biphenotypic acute leukemia (BAL) (4.2%); and ALL (77.1%), including the subtypes B-ALL (72.9%) and T-ALL (27.1%). Among the children with ALL, there were no statistically significant differences between patients with and without aberrant phenotypes, in relation to hematological parameters and treatment response.
  
  
  CONCLUSIONS
  This work demonstrates that the frequencies of AML M0 cases among adults and T-ALL cases among children in Maranhão were high. This suggests that there may be differences in AML subtype incidence, as seen with ALL subtypes, in different regions of Brazil. No association was found between the expression of aberrant phenotypes and prognostic factors, in children with ALL.
authors.affiliation: Clinical Research Center, University Hospital, Universidade Federal do Maranhão, São Luís, Maranhão, Brazil. eldanoronha@yahoo.com.br
authors.forename: Elda Pereira
authors.initials: EP
authors.lastname: Noronha
authors.forename: Heliana Trindade
authors.initials: HT
authors.lastname: Marinho
authors.forename: Erika Bárbara Abreu Fonseca
authors.initials: EB
authors.lastname: Thomaz
authors.forename: Cintia Assunção
authors.initials: CA
authors.lastname: Silva
authors.forename: Geni Lourdes Ramos
authors.initials: GL
authors.lastname: Veras
authors.forename: Raimundo Antônio Gomes
authors.initials: RA
authors.lastname: Oliveira
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D004812:Epidemiologic Methods; D006801:Humans; D016130:Immunophenotyping; D007223:Infant; D007938:Leukemia / Q000145:classification / Q000175:diagnosis* / Q000453:epidemiology; D008875:Middle Aged; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis / Q000453:epidemiology; D011379:Prognosis; D055815:Young Adult