Long-term Outcomes And Prognostic Factor Analysis Of 330 Children With Acute Lymphoblastic Leukemia

Objective:To retrospectively analyze the long-term outcomes and prognostic factors in childhood acute lymphoblastic leukemia(ALL).Methods:408 cases of acute lymphoblastic leukemia in children were diagnosed at the department of hematology-oncology of the affiliated children’s hospital of Zhejiang University School of Medicine from January,2009 through December,2012.Seventy eight patients were excluded from the survival analysis,of whom,refused to receive any treatment or less than 14 days of chemotherapy.The remaining 330 cases accepted modified National Protocol of Childhood ALL in China 2009(NPCAC-ALL-2009)and were eligible for the survival and prognosis analysis.Patients were followed-up via telephone calls or outpatient clinic visits.All statistical analyses were performed with SPSS 21.0 software.Results:Of the 330 cases who accepted effective therapy,37 cases had relapse,including 34 cases with bone marrow relapse,1 case with CNS relapse,1 case with testicular relapse,and 1 case with both testicular and bone marrow relapses.The total 5-year accumulative relapse rate was 11.2%.Survival analysis of the 330 cases showed that the 5-year overall survival(OS)and event free survival(EFS)rates were(86.3± 1.9)%and(81.2±2.2)%,respectively.Prognostic factor analysis showed that gender,initial Hb concentration,Plt count,ALT level,AST level,FAB morphological classification,EA2/PBX1 fusion gene positive,EVI1 mutation positive,TEL/AML1 positive,Hypodiploid(<44 chromosomes),hyperdiploid(>50 chromosomes)did not have significant impact on the long-term prognosis of ALL in this cohort,while age(≤10 year or<lyear),initial lymphnode size ≥1cm3,initial white blood cell count(≥100×109/L),initial LDH level ≥600U/L),d15-MRD level(≥0.01%),d33-MRD level(≥0.01%),T-ALL,MLL related gene rearrangement were the unfavorable prognostic factors(P=0.000,0.012,0.000,0.031,0.002,0.000,0.000 and 0.005,respectively).Multivariate Cox regression analysis showed that age(≥10 year or<1year)(RR=2.224,P=0.023),initial white blood cell count(≥100×109/L)(RR=3.441,P=0.006)5 d33-MRD level(≥0.01%))(RR=3.596,P=0.003)were the unfavorable prognostic factors.Conclusion:330 cases of pediatric ALL recently treated in our hospital have been improved 5-year OS of(86.3± 1.9)%and 5-year EFS of(81.2±2.2)%,respectively.The total 5-ywith ear accumulative relapse rate is 11.2%.Age(≥10 year or<1 year),initial lymphnode size>lcm3,initial white blood cell count(≥100×109/L),initial LDH level(≥600U/L),d15-MRD level(>0.01%),d33-MRD level(≥0.01%),T-ALL,and MLL related gene rearrangement are the poor prognostic factors.