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Purpose@#Chemotherapy has been the primary treatment for patients with B-cell acute lymphoblastic leukemia (B-ALL). However, there are still patients who are not sensitive to chemotherapy, including those with refractory/relapse (R/R) disease and those experiencing minimal residual disease (MRD) re-emergence. Chimeric antigen receptor-T lymphocytes (CAR-T) therapy may provide a new treatment option for these patients. @*Materials and Methods@#Our institution conducted a single-arm prospective clinical trial (ChiCTR-OPN-17013507) using CAR-T-19 to treat R/R B-ALL and MRD re-emergent patients. One hundred and fifteen patients, aged 1-25 years (median age, 8 years), were enrolled, including 67 R/R and 48 MRD re-emergent CD19-positive B-ALL patients. @*Results@#All patients achieved morphologic complete remission (CR), and within 1 month after infusion, 111 out of 115 (96.5%) patients achieved MRD-negative CR. With a median follow-up time of 48.4 months, the estimated 4-year leukemia-free survival (LFS) rate and overall survival (OS) rate were 68.7%±4.5% and 70.7%±4.3%, respectively. There were no significant differences in long-term efficacy observed among patients with different disease statuses before infusion (4-year OS: MRD re-emergence vs. R/R B-ALL, 70.6%±6.6% vs. 66.5%±6.1%, p=0.755; 4-year LFS: MRD re-emergence vs. R/R B-ALL, 67.3%±7.0% vs. 63.8%±6.2%, p=0.704). R/R B-ALL patients bridging to transplantation after CAR-T treatment had a superior OS and LFS compared to those who did not. However, for MRD re-emergent patients, there was no significant difference in OS and LFS, regardless of whether they underwent hematopoietic stem cell transplantation or not. @*Conclusion@#CD19 CAR-T therapy effectively and safely cures both R/R B-ALL and MRD re-emergent patients.
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OBJECTIVE@#To explore the consistency of flow cytometry (FCM) method and polymerase chain reaction (PCR) technique in the detection of minimal residual disease (MRD) at different treatment stages in pediatric patients with TCF3/PBX1+ B-cell acute lymphoblastic leukemia (B-ALL) and the correlations between the detection results and prognosis.@*METHODS@#The clinical data of 64 newly diagnosed pediatric patients with TCF3/PBX1+ B-ALL admitted to the Department of Pediatrics of Peking University People's Hospital from January 2005 to December 2017 were retrospectively analyzed. FCM and PCR methods were used to monitor the MRD level in bone marrow samples from 64 children during the same period of treatment on d33 and d90 respectively, and the detection results were analyzed.@*RESULTS@#There were 37 males and 27 females in the 64 patients, with a median age of 8 years(range 0.8 to 16 years). The complete remission (CR) rate after the first cycle of induction chemotherapy was 98.4% (62/63), with overall CR rate of 100%. 12 patients experienced recurrence, with a median recurrence time of 16.9 (5.3-46.3) months. The median follow-up time of the 64 patients was 77.2 (1.0-184.8) months , and the 5-year overall survival (OS) rate and event-free survival (EFS) rate were 82.8%±4.7% and 75.0%±5.4%, respectively. On d90, the concordance rate of the MRD results from the two methods was 98.4%, and the related kappa value was 0.792 (P < 0.001), which were significantly higher than those on d33. After induction chemotherapy (d33), the 5-year EFS rate of MRD-FCM- group (79.3%±5.3%) was significantly better than that of MRD-FCM+ group (40.0%±21.9%) (P =0.028), there were no significant differences in the 5-year OS rate and EFS rate between MRD-PCR+ group and MRD-PCR- group, and the 5-year EFS rate of MRD-FCM-/PCR- group (85.4%±5.5%) was significantly better than that of MRD-FCM+/PCR+ group (40.0 %±21.9%) (P =0.026).@*CONCLUSION@#In children with TCF3/PBX1+ B-ALL, the MRD results detected by FCM and PCR methods show good consistency, especially in consolidation therapy period (d90). The MRD level at the end of induction therapy (d33) is an important factor affecting the long-term prognosis, especially the MRD results detected by FCM method, which is significantly associated with prognosis.
Subject(s)
Male , Female , Child , Humans , Infant , Child, Preschool , Adolescent , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Neoplasm, Residual/diagnosis , Clinical Relevance , Retrospective Studies , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma , Prognosis , Burkitt Lymphoma , Basic Helix-Loop-Helix Transcription Factors/therapeutic useABSTRACT
OBJECTIVES@#To study the clinical and prognostic significance of the preferentially expressed antigen of melanoma (PRAME) gene in the absence of specific fusion gene expression in children with B-lineage acute lymphoblastic leukemia (B-ALL).@*METHODS@#A total of 167 children newly diagnosed with B-ALL were enrolled, among whom 70 were positive for the PRAME gene and 97 were negative. None of the children were positive for MLL-r, BCR/ABL, E2A/PBX1, or ETV6/RUNX1. The PRAME positive and negative groups were analyzed in terms of clinical features, prognosis, and related prognostic factors.@*RESULTS@#Compared with the PRAME negative group, the PRAME positive group had a significantly higher proportion of children with the liver extending >6 cm below the costal margin (P<0.05). There was a significant reduction in the PRAME copy number after induction chemotherapy (P<0.05). In the minimal residual disease (MRD) positive group after induction chemotherapy, the PRAME copy number was not correlated with the MRD level (P>0.05). In the MRD negative group, there was also no correlation between them (P>0.05). The PRAME positive group had a significantly higher 4-year event-free survival rate than the PRAME negative group (87.5%±4.6% vs 73.5%±4.6%, P<0.05), while there was no significant difference between the two groups in the 4-year overall survival rate (88.0%±4.4% vs 85.3%±3.8%, P>0.05). The Cox proportional-hazards regression model analysis showed that positive PRAME expression was a protective factor for event-free survival rate in children with B-ALL (P<0.05).@*CONCLUSIONS@#Although the PRAME gene cannot be monitored as MRD, overexpression of PRAME suggests a good prognosis in B-ALL.
Subject(s)
Child , Humans , Acute Disease , Antigens, Neoplasm/therapeutic use , Neoplasm, Residual/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , PrognosisABSTRACT
OBJECTIVE@#To explore the impact of induction treatment response on the prognosis of pediatric core binding factor-acute myeloid leukemia (CBF-AML).@*METHODS@#The result of induce reaction and survival data of 157 pediatric CBF-AML patients in our hospital from September 2008 to December 2018 were retrospectively analyzed.The survival rate of the patients with different degrees of morphological remission after induction chemotherapy was comparative analyzed.@*RESULTS@#Among the 157 children with CBF-AML, 113 (72.4%) patients achieved morphologic leukemia-free state (MLFS) after the first course of induction chemotherapy, 153 (98.1%) patients achieved MLFS after the second course of induction chemotherapy. The 5-year event-free survival (EFS) rate and 5-year overall survival (OS) rate of patients with non-remission (NR) status after the first course of induction of chemotherapy was significantly lower than the patients achieved MLFS and the patients achieved partial remission (PR). The 5-year EFS rate and 5-year OS rate of the patients with PR status after the second course of induction chemotherapy were lower than the patients achieved MLFS, but the difference was not statistically significant. Multivariable analyze showed that NR after the first course of induction chemotherapy and myeloid sarcoma were the independent risk factors affecting EFS of the patients. There were six patients with NR status after the first course of induction chemotherapy, in which all of them harbored t(8;21), three of them with sex chromosome deletion, two of them with myeloid sarcoma.@*CONCLUSION@#NR status after the first course of induction chemotherapy was the independent risk factor affecting EFS and OS of CBF-AML patients, it can be taken as an indicator for higher risk stratification. PR status after the first course of induction chemotherapy may not be used as a diagnostic criterion for primary drug resistance.
Subject(s)
Child , Humans , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Core Binding Factors , Disease-Free Survival , Induction Chemotherapy , Leukemia, Myeloid, Acute/drug therapy , Prognosis , Remission Induction , Retrospective StudiesABSTRACT
OBJECTIVE@#To study the influence of dasatinib treatment on body height in children with acute myeloid leukemia (AML).@*METHODS@#A retrospective analysis was performed for the clinical data of 86 AML children aged <17 years. According to the treatment regimen, these children were divided into a conventional chemotherapy group and a dasatinib chemotherapy group. The 57 children in the conventional chemotherapy group were given conventional chemotherapy drugs without tyrosine kinase inhibitor, and the 29 children in the dasatinib chemotherapy group were given conventional chemotherapy drugs and dasatinib. The two groups were compared in terms of height standard deviation score (HtSDS) at the beginning of treatment and after treatment, as well as the change in HtSDS after 1 and 2 years of treatment.@*RESULTS@#There was no significant difference in HtSDS between the conventional and dasatinib chemotherapy groups before treatment. Within the first two years of treatment, the dasatinib chemotherapy group had a similar change trend of HtSDS as the conventional chemotherapy group. Four children in the dasatinib chemotherapy group reached the final adult height during follow-up, which was significantly lower than the target height (P=0.044). In the conventional chemotherapy group, there was no significant difference between final adult height and target height. In the dasatinib chemotherapy group, the children in adolescence had a significant change in HtSDS after treatment (P=0.032).@*CONCLUSIONS@#Dasatinib treatment may affect the final height of children with AML, and the use of dasatinib after the beginning of adolescence may lead to growth disorder, but dasatinib treatment has little effect on body height in the short-term treatment.
Subject(s)
Adolescent , Child , Humans , Body Height , Dasatinib , Therapeutic Uses , Growth Disorders , Leukemia, Myeloid, Acute , Drug Therapy , Retrospective StudiesABSTRACT
OBJECTIVE@#To explore the clinical-biological characteristics and prognosis of pediatric pro-B cell acute lymphoblastic leukemia (pro-B-ALL).@*METHODS@#A total of 64 patients aged less than 18 years old with pro-BALL were enrolled. Clinical characteristics, therapeutic effect and prognostic factors were retrospectively analyzed.@*RESULTS@#Pro-B-ALL occurred in 6.23% (64/1 028) of pediatric ALL. Among the 64 patients, 35 were male and 29 were female. The median age was 7.0 years (range 0.4-16.0 years) at diagnosis, of which 39% and 6% were ≥ 10 years old and < 1 year old respectively. The median WBC count was 25.5×10@*CONCLUSIONS@#Pediatric pro-B ALL is a heterogeneous disease with clinical and biological diversity. Biological characteristics, such as immunological markers, genetic alterations, and MRD at 3 months after chemotherapy may be important factors for the long-term prognosis.
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Infant , Male , Antigens, CD/genetics , Disease-Free Survival , Histone-Lysine N-Methyltransferase/genetics , Myeloid-Lymphoid Leukemia Protein/genetics , Neoplasm, Residual/diagnosis , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Prognosis , Retrospective StudiesABSTRACT
Objective: To analyze the clinical outcome and the prognostic factor in pediatric patients with core binding factor-acute myeloid leukemia (CBF-AML). Methods: A total of 121 newly diagnosed pediatric CBF-AML patients enrolled from Aug. 2005 to Sep. 2017 were retrospectively reviewed. Cumulative incidence of relapse (CIR), event-free survival (EFS) and overall survival (OS) rates were estimated by Kaplan-Meier method and prognostic factors were evaluated by Cox regression with SPSS. Results: Of the 121 patients, 120 patients were assessed for bone marrow remission after induction chemotherapy. 100 cases (83.3%) achieved complete remission (CR) after the first course of chemotherapy. 119 cases (99.2%) achieved CR after the second course of chemotherapy. Of the 121 patients, 13 patients (10.7%) had recurrence with the median interval of recurrence as 13.8 months (3.7 to 58.8 months). 17 patients (14.0%) died. The CIR, EFS and OS at 3 years were 12.7%, 77.5% and 82.8%, respectively. The factors including age at diagnosis, sex, initial WBC count, presence of extramedullary leukemia, C-KIT expression, additional chromosomal abnormalities, and CR after the first course of chemotherapy were analyzed by multivariate regression analysis of Cox. Multivariate analysis identified that additional chromosomal abnormalities was the only independent risk factor affecting OS (HR=4.289, 95%CI 1.070-17.183, P=0.040). Conclusions: Pediatric CBF-AML was a unique setting of prognostic subtypes. Chemotherapy produced good responses. Additional chromosomal abnormalities was the only independent risk factor for OS in pediatric CBF-AML.
Subject(s)
Child , Humans , Core Binding Factors , Disease-Free Survival , Leukemia, Myeloid, Acute , Prognosis , Remission Induction , Retrospective StudiesABSTRACT
Objective: To evaluate the safety and efficacy of chimeric antigen receptors T cells (CAR-T) in childhood acute B lymphoblastic leukemia (B-ALL) to probe the prognosis-related factors. Methods: Forty-eight children, 29 boys and 19 girls, aged 3-17years old (median age was 8 years old) , with recurrent or refractory CD19 positive B-ALL, were treated by the CD19 specific CAR-T cells. A total of 48 cases received 61 infusions. Flow cytometry or real-time quantitative polymerase chain reaction method were used to monitor micro residual disease (MRD) . The follow-up period was from 16 to 1 259 days with the median follow-up of 406 days. SPSS software was used to statistical analysis. Results: No adverse reaction was observed during 61 infusions. The most common adverse reaction after CAR-T cell infusions was cytokine-release syndrome (CRS) . Only 2 cases experienced level 3 CRS performance, including continuous high fever, convulsions, delirium, serous cavity effusion, and decreasing of blood pressure. Tocilizumab was given to release CRS performance. No treatment-related death occurred. Thirty-seven patients showed response during 7 to 28 days after infusions. The early response rate was 77.1%, with MRD before infusion less than 5% group higher than the MRD more than 5% group (87.1% vs 58.8%, χ2=4.968, P=0.036) . For the 37 patients who showed response to CAR-T cell infusions, univariate analysis identified that age, disease status at the time of treatment, MRD before infusion affected 2-year OS rate (P<0.05) . Multivariate prognostic analysis for EFS disclosed that the MRD before infusion more than 5% (RR=3.433, 95% CI 1.333-8.844, P=0.011) and not bridge to HSCT (RR=4.996, 95% CI 1.852-13.474, P=0.001) were the independent risk factors. Conclusion: The fourth generation CAR-T cells directed against CD19 could effectively and safely treat relapsed and refractory B-ALL, which implicated that CAR-T therapy as a novel therapeutic approach could be useful for patients with relapsed or refractory B-ALL who have failed all other treatment options. Reducing MRD as far as possible by effective pretreatment chemotherapy was in favor of increasing the response rate. Bridging HSCT after CAR-T cell treatment might be a better therapeutic strategy for the patient with refractory or molecular relapsed B-ALL.
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Male , Antigens, CD19 , Follow-Up Studies , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Receptors, Antigen, T-Cell , Receptors, Chimeric Antigen , T-LymphocytesABSTRACT
Objective: To explore the clinical features and prognostic factors of Ph-positive and/or BCR-ABL positive acute lymphoblastic leukemia (Ph+ ALL) in children. Methods: The clinical data of 68 Ph+ ALL children who were treated at Peking University People's Hospital from December 2006 to December 2016 was retrospectively reviewed. Survival analysis were estimated by Kaplan-Meier method. Univariate analysis was estimated by Log-rank test and Chi-square, and multivariate analysis was estimated by Cox proportional hazards regression model. Results: In the 68 cases, the proportion of male to female was 2.1∶1, with a median age of 8 (1-16) years, and the median overall survival (OS) and disease free survival (DFS) were 16.8 months and 13.5 months, respectively. The early response rate to treatment was 43.9%, with myeloid-antigens-expression group lower than the non-expression group (29.6% vs 61.3%, χ2=5.814, P=0.020); The complete remission (CR) rate after one-course induction therapy was 86.2% (56/65), with good-response group higher than the poor-response group (100.0% vs 74.2%, χ2=6.680, P=0.003);The CR rate after induction in patients receiving imatinib plus chemotherapy was higher than the patients receiving chemotherapy only (94.9% vs 73.1%, χ2=5.185, P=0.024). The 2-and 5-year OS were (61.4±7.0)% and (50.8±8.1)%, respectively. The 2-and 5-year DFS were (54.6±6.8)% and (48.6±7.3)%, respectively. Univariate analysis showed that the initial WBC, LDH, spleen size, liver size, with-myeloid-antigens-expression, early response to treatment, MRD (BCR-ABL) after one-course induction, application of imatinib and different treatment options affected 2-year OS rate (all P<0.05). LDH, spleen size, liver size, with-myeloid-antigens-expression, early response to treatment, MRD (BCR-ABL) after one-course induction, application of imatinib and different treatment options affected 2-year DFS rate (all P<0.05). Multivariate prognostic analysis for OS (RR=45.7, 95% CI 1.4-1 528.2, P=0.033) and DFS (RR=52.3, 95% CI 1.6-1 725.9, P=0.026) showed that the spleen ≥ 3 cm was the independent risk factor. Conclusions: Pediatric Ph+ ALL is a special condition with unique clinical and biological features. The early response to treatment was poor in patients with myeloid-antigens-expression, which resulted in a low CR rate after one-course induction and the administration of imatinib can remarkably improve the CR rate. Initial spleen ≥ 3 cm is an independent prognostic factor. The efficacy of chemotherapy alone is poor, and imatinib combined with chemotherapy is applauded in the aim of improving outcomes.
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Infant , Male , Antineoplastic Combined Chemotherapy Protocols , Benzamides , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Prognosis , Remission Induction , Retrospective Studies , Treatment OutcomeABSTRACT
<p><b>OBJECTIVE</b>To study the relationship between loss of sex chromosomes and prognosis in children with acute myeloid leukemia (AML) M2 subtype.</p><p><b>METHODS</b>According to cytogenetic characteristics, 106 children with AML were divided into three groups: patients with normal karyotype (Group A, n=26), patients with abnormal karyotype who had no loss of sex chromosomes (Group B, n=52), and patients with abnormal karyotype who had loss of sex chromosomes (Group C, n=28). Prognosis was compared between the three groups.</p><p><b>RESULTS</b>The 5-year event-free survival (EFS) rates of Groups A, B, and C were (38.9±11.2)%, (59.3±7.3)%, and (66.5±10.5)%, respectively; the EFS of Group C was significantly higher than that of Group A (P=0.035). The 5-year overall survival (OS) rates of Groups A, B, and C were (54.3±13.5)%, (68.1±7.7)%, and (77.9±9.8)%, respectively (P>0.05). The 5-year EFS of 58 patients with t(8;21) was (63.3±7.3)%, significantly higher than that of patients with normal karyotype (P=0.015). All the 28 cases in Group C had t(8;21), and their 5-year EFS was not significantly different from that of patients with t(8;21) in Group B (P>0.05).</p><p><b>CONCLUSIONS</b>Loss of sex chromosomes is a favorable karyotype in children with AML M2 subtype and the patients in this group mostly have t(8;21). Why loss of sex chromosomes indicates a favorable prognosis is probably because it is accompanied by t(8;21) in the patients.</p>
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Male , Chromosomes, Human, Pair 21 , Chromosomes, Human, Pair 8 , Karyotype , Leukemia, Myeloid, Acute , Genetics , Mortality , Prognosis , Sex Chromosome Aberrations , Translocation, GeneticABSTRACT
<p><b>OBJECTIVE</b>To explore the efficacy and adverse effects of clofarabine for relapsed/refractory acute lymphoblastic leukemia in children.</p><p><b>METHODS</b>Twenty-six pediatric patients with relapsed/refractory acute lymphoblastic leukemia were treated with clofarabine. There were 22 males and 4 females, with a mean age of 9.5 years (ranging from 4 to 17 years). They received clofarabine 52 mg/m2 intravenously over 2 hours daily for 5 days. Thirteen patients received two cycles and one patient received three cycles.</p><p><b>RESULTS</b>In the first cycle of clofarabine, complete remission was obtained in 11 children (42%) and partial remission was obtained in 7 children (27%). Eight children (31%) were considered unresponsive. In the second cycle, 11 (85%) of the 13 children obtained complete remission, 1 (8%) partial remission and 1 (8%) was unresponsive. One child received three cycles and obtained complete remission in each cycle. The common adverse events were myelosuppression, infection, liver dysfunction and gastrointestinal adverse reactions. There were no chemotherapy-related deaths.</p><p><b>CONCLUSIONS</b>Clofarabine is effective in the treatment of children with relapsed/refractory acute lymphoblastic leukemia and its adverse effects can be tolerated. Clofarabine could be a promising new treatment for relapsed/refractory acute lymphoblastic leukemia.</p>
Subject(s)
Adolescent , Child , Child, Preschool , Female , Humans , Infant , Male , Adenine Nucleotides , Therapeutic Uses , Antineoplastic Agents , Therapeutic Uses , Arabinonucleosides , Therapeutic Uses , Follow-Up Studies , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Drug Therapy , RecurrenceABSTRACT
Objective To investigate the clinical characteristics and risk factors of childhood acute leukemia (AL) with severe neurologic complications.Methods From Jun.1991 to Mar.2011,26 AL patients with severe neurologic complications in Peking University People's Hospital were enrolled.The incidence,clinical features,and risk factors for severe neurologic complications were retrospectively analyzed.Results There 26 patients included 8 cases of acute lymphoblastic leukemia,17 cases of acute myeloid leukemia(AML) and 1 case of acute mixed lineage leukemia.There were 20 patients taking CT scan and 17 patients were confirmed with intracranial hemorrhage.Six cases of AML without CT scan were dead.The patients suffering from intracranial hemorrhage all had intraparenchymal hemorrhage.The AML-M5 with intracranial hemorrhage had higher white blood cell count and higher level of L-lactate dehydrogenase than those without intracranial hemorrhage.These were 5 cases(31.25%) of AML with platelet count < 20 × 109/L,12 cases(70.58%) of AML with prolonged prothrombin time,7 cases(41.17%) of AML with prolonged activated partial thromboplastin time,and 8 cases(47.06%) of AML with low fibrinogen when the severe neurologic complication occurred.Conclusions The most common type of severe neurologic complications of childhood AL is intracranial hemorrhage.The patients with AML are prone to occur intracranial hemorrhage.Intensive blood production transfusion may be beneficial to reduce the probability of intracranial hemorrhage in these patients.
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To improve the effect of pediatrics clinical probation teaching for eight-year program medical students,the exploration and practice of case-based instruction teaching with symptoms as main line,reading reports,and application of high quality counterfeit baby simulator-assisted instruction were carried out,which could inspire students' learning interest,and contribute to the training of students'clinical and scientific thought,their self-education and clinical skills.
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<p><b>OBJECTIVE</b>To investigate whether there were differences in the clinical characteristics, cytogenetic characteristics, immunophenotype and prognosis in children with B cell type acute lymphoblastic leukemia (B-ALL) carrying different fusion genes.</p><p><b>METHODS</b>The research included 80 children with B-ALL from Peking University People's Hospital between March 2006 and December 2008. Eighteen children were positive for TEL/AML1, 14 for E2A/PBX1, 11 for BCR/ABL,and 2 cases for MLL/AF4, and 35 cases were negative for all of the 4 fusion genes. Data including clinical characteristics, morphology, immunophenotype and cytogenetic characteristics were collected, and the disease-free survival (DFS) was evaluated. The children were followed up until April 2009.</p><p><b>RESULTS</b>In the 18 children with TEL/AML1+B-ALL, 66.7% were younger than 5 years old. They had low tumor load. FAB-L2 morphology was commonly observed, but t(12;21) was often absence in these children. Up to now,17 children who survived were disease-free. In the 14 children with E2A/PBX1+B-ALL, the majority were female. Thirteen children showed FAB-L1 morphology. Twelve children showed pre-B-ALL immunophenotype. The EFS was close to 80%. In the 11 children with BCR/ABL+B-ALL, 10 children showed common B type immunophenotype. FAB-L1 and FAB-L2 morphology was found in 4 children respectively. The DFS was less than 20%. Two children with MLL/AF4 positive B-ALL had high tumor load. Their morphologic diagnosis was FAB-L1. Both showed the Pro-B-ALL immunophenotype. One child discontinued treatment at the early stage of chemotherapy, and the other child survived disease-free until now.</p><p><b>CONCLUSIONS</b>The B-ALL children with different fusion genes have different clinical characteristics, immunophenotypes and prognosis.</p>