RESUMO
Recently, DNA methyltransferase 3A (DNMT3A) mutations have been identified in acute myeloid leukemia (AML), the highest frequency being found within cytogenetically normal (CN) AML. In this study, diagnostic samples from 123 adults younger than 60 years with primary CN-AML homogeneously treated in the Acute Leukemia French Association-9801 and -9802 trials were screened for mutations in DNMT3A-conserved domains by direct sequencing. Patients were also assessed for the presence of FLT3 (fms-like tyrosine kinase receptor-3), NPM1 (nucleophosmin), CEBPA, WT1 (Wilms tumor 1), IDH1 (isocitrate dehydrogenase 1) and IDH2 mutations. Thirty-eight mutations were detected in 36 patients (29%): 36 nucleotide substitutions, mostly affecting amino-acid residue R882 and two frameshift deletions. DNMT3A mutations were significantly associated with the French-American-British subtypes M4/M5 and the presence of NPM1 mutations. In the whole cohort, DNMT3A mutated patients had a shorter event-free survival (5-year EFS: 13% vs 32%, P = 0.02) and overall survival (5-year OS: 23% vs 45%, P = 0.02) compared with DNMT3A wild-type patients. In multivariate analysis including age, white blood cell count, NPM1/FLT3-internal tandem duplication/CEBPA risk group and DNMT3A mutational status, the presence of a DNMT3A mutation remained an independent adverse prognostic factor for EFS and OS, suggesting that testing for DNMT3A mutations could help further improve risk stratification in CN-AML.
Assuntos
Biomarcadores Tumorais/genética , Análise Citogenética , DNA (Citosina-5-)-Metiltransferases/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Mutação/genética , Adolescente , Adulto , DNA Metiltransferase 3A , DNA de Neoplasias/genética , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/classificação , Masculino , Pessoa de Meia-Idade , Nucleofosmina , Reação em Cadeia da Polimerase , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Adulto Jovem , Tirosina Quinase 3 Semelhante a fms/genéticaRESUMO
Post-remission options were compared in a population of 262 relapsing and refractory acute myeloid leukemia patients achieving complete remission (CR) after the same re-induction according to etoposide - mitoxantrone - cytarabine (EMA) trials. The selection of post-remission therapy depended on trial recommendations, age, performance status, and availability of an HLA-identical sibling. One hundred and thirty patients received chemotherapy consolidation courses, 50 received autologous stem cell transplantation (SCT), and 43 underwent allogeneic bone marrow transplantation (BMT), while 39 did not receive any additional therapy. The preliminary analysis identified 3 favorable prognostic factors correlated with event-free survival (EFS): M3 subtype, previous CR duration > 1 year, and transplantation. Three year EFS was 68 vs. 23% with autologous SCT and allogeneic BMT in M3 patients and, respectively, 41 vs. 20% in non-M3 patients. Three year probabilities of treatment-related mortality were 11 and 47%, respectively. A statistical model was conceived with adjustment on prognostic factors and post-remission option. In the multivariate analysis, autologous SCT appeared significantly better than allogeneic BMT (P < 0.01) or chemotherapy (P = 0.001), while allogeneic BMT was not statistically different than chemotherapy. This indicates a high treatment-related toxicity with allogeneic BMT in patients re-induced by highly intensive chemotherapy, and therefore a tendency for a better outcome with autologous SCT as post-remission treatment in those patients.