[A long-term follow-up study of 82 children with acute myeloid leukemia]

Objective: To investigate the efficacy and the prognostic factors of Chinese Academy of Medical Sciences 2005 (CAMS-2005) regimen in the treatment of pediatric acute myeloid leukemia (AML). Methods: Eighty-eight cases of newly-diagnosed AML patients, who were treated with the CAMS-2005 regimen from April 2005 to July 2009, were enrolled in this case observational study. Clinical characteristics, long-term prognosis and prognostic factors were analyzed retrospectively. Overall survival (OS) and event free survival (EFS) rates were estimated by the Kaplan-Meier method. Rates of survival between the groups were compared by the Log-rank test. Prognostic factors were evaluated by COX regression analysis. Results: A total of 82 cases were enrolled in this study, including 34 core binding factor(CBF)-AML patients and 48 non-CBF-AML patients. There were 45 males and 37 females. The median age at diagnosis was 8.0 (0.7-16.0) years. During the induction therapy, 3 patients (4%) developed treatment-related early-death, while 63 patients (77%) achieved complete remission (CR) and 53 patients (65%) achieved CR after 1 course. Twenty-one patients (33%) had relapsed disease. The CR rates of CBF-AML patients and non-CBF-AML patients were 91% (31/34) and 67% (32/48) (χ(2)=5.410, P=0.020) , while the relapse rates were 29% (9/31) and 38% (12/32) (χ(2)=0.508, P=0.476) . The 8-year OS and EFS rates of all 82 patients were 59%(48/82) and 51%(42/82). The 8-year OS rates of CBF-AML patients and non-CBF-AML patients were 74% (25/34) and 48%(23/48) (χ(2)=5.812, P=0.016), while the 8-year EFS rates of CBF-AML patients and non-CBF-AML patients were 71%(24/34) and 38%(18/48) (χ(2)=8.682, P=0.003). There were statistically significant differences between groups. The 8-year OS rates of patients who achieved CR after 1 course and other patients were 68% (36/53) and 46% (12/26) (χ(2)=9.606, P=0.002), while the 8-year EFS rates were 66% (35/53) and 27% (7/26) (χ(2)=19.471, P=0.000), the differences were all statistically significant. COX multivariate analysis showed that CBF-AML or non-CBF-AML and whether achieved CR after 1 course were independent prognostic factors of OS rates (relative risk: 2.538, 2.561) and EFS rates (relative risk: 3.050, 3.686) (P <0.05). Conclusions: The efficacy of the CAMS-2005 regimen in the treatment of AML patients was well. CBF-AML or non-CBF-AML and whether achieved CR after 1 course were independent prognostic factors for pediatric AML patients.