RESUMO
CONTEXT AND OBJECTIVES: 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. DESIGN AND SETTING: 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 percent) and acute myeloid leukemia (AML) (77.3 percent). The subtype AML M0 occurred most frequently (29.4 percent). In children (n = 48), the types were: AML (18.7 percent), most frequently subtype AML M4 (33.4 percent); biphenotypic acute leukemia (BAL) (4.2 percent); and ALL (77.1 percent), including the subtypes B-ALL (72.9 percent) and T-ALL (27.1 percent). 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. CONCLUSION: 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.
CONTEXTO E OBJETIVOS: A incidência dos subtipos de leucemias agudas (LA) tem mostrado variações em relação à distribuição geográfica. Objetivou-se determinar a incidência dos subtipos morfológicos e imunofenotípicos de LA no estado do Maranhão, Brasil, e relacionar a expressão de fenótipos aberrantes em crianças com leucemia linfoblástica aguda (LLA) com fatores prognósticos. TIPO DE ESTUDO E LOCAL: Estudo de coorte único prospectivo em um centro oncológico de referência público no Maranhão. MÉTODOS: Diagnosticaram-se 70 casos de LA no período de setembro de 2008 a janeiro de 2010. No diagnóstico, realizaram-se hemogramas, mielogramas (no diagnóstico e ao final da fase de indução), citoquímica e imunofenotipagem. RESULTADOS: Nos pacientes adultos (n = 22), as incidências dos tipos de LA foram: LLA (22,7 por cento) e leucemia mieloide aguda (LMA) (77,3 por cento), sendo o subtipo LMA M0 mais frequente (29,4 por cento). Em crianças (n = 48): LMA (18,7 por cento), subtipo LMA M4 mais frequente (33,4 por cento), leucemia bifenotípica aguda (BAL) (4,2 por cento) e LLA (77,1 por cento), sendo os subtipos LLA-B (72,9 por cento) e LLA-T (27,1 por cento). Na LLA, em crianças, não se encontrou diferença estatisticamente significante entre pacientes com e sem fenótipos aberrantes, em relação aos parâmetros hematológicos e resposta ao tratamento. CONCLUSÃO: Esta pesquisa demonstra elevada frequência de casos de LMA M0 em adultos, bem como das LLA-T em crianças no Maranhão, sugerindo que podem haver diferenças na incidência dos subtipos das LMA, assim como dos subtipos de LLA, em diferentes regiões do Brasil. Não foi encontrada associação entre a expres de fenótipos aberrantes e fatores prognósticos em crianças com LLA.
Assuntos
Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Humanos , Lactente , Pessoa de Meia-Idade , Adulto Jovem , Imunofenotipagem , Leucemia/diagnóstico , Distribuição por Idade , Brasil/epidemiologia , Métodos Epidemiológicos , Leucemia/classificação , Leucemia/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , PrognósticoRESUMO
CONTEXT AND OBJECTIVES: 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. DESIGN AND SETTING: 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. CONCLUSION: 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.