Minimal residual disease (MRD), a crucial biomarker for assessing efficacy and predicting recurrence, refers to residual tumor cells remaining in the body of patients with hematological malignancies who achieved complete remission after treatment. This study aimed to conduct a retrospective analysis of the clinical diagnosis, treatment, and MRD monitoring of a pediatric patient with multiple acute B-lymphocytic leukemia relapses, alongside a review of relevant literature. In this case, Ig rearrangement based on next-generation sequencing (NGS) was more accurate in assessing the MRD level, compared with the traditional method of MRD detection, indicating the risk of earlier relapse and guided interventions in time. Additionally, NGS-MRD detected clonal evolution, providing new ideas to further investigate the intrinsic factors of disease development.

This case report presents a patient with pediatric acute myeloid leukemia (AML) with RUNX1∷MTG16, admitted to the Blood Disease Hospital of the Chinese Academy of Medical Sciences in October 2023. He was 13 years old, with a chief complaint of fatigue for 20 days. Bone marrow smear revealed 17.0% blasts, the karyotype was 46,XY,t (16; 21) (q24; q22), molecular biology demonstrated RUNX1∷MTG16 fusion gene, combined with FLT3-ITD mutation. The child was diagnosed with AML (with RUNX1 ∷ MTG16). Complete remission was achieved after chemotherapy induction. The induction therapy regimen was mitoxantrone hydrochloride liposomes combined with cytarabine (MA). The RUNX1 ∷ MTG16 and FLT3-ITD were negative after another MA treatment course. However, the RUNX1 ∷ MTG16 and FLT3-ITD were turning positive during the following intensive treatment, and he then successfully underwent matched sibling donor umbilical cord blood transplantation.

Objective:To evaluate the clinical and prognostic differences in acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) children under different diagnostic criteria (World Health Organization (WHO) 2016 and WHO 2022 criteria).Methods:In this retrospective cohort study, clinical characteristics and prognosis information of 260 acute myeloid leukemia (AML) children admitted to Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences from August 2017 to August 2021 were analyzed retrospectively. According to WHO 2016 and WHO 2022 diagnostic criteria, patients were divided into AML-MRC group and non-AML-MRC group, the prognostic and genetic differences between two groups were compared respectively. Meanwhile, the characteristics of children with 8 MRC-related genes defined in WHO 2022 diagnostic criteria were described. Mann-Whitney U test, chi-square test were used for comparison between groups. Survival curve was plotted by Kaplan-Meier method, and comparison between groups was performed by Log-Rank method. Results:Among the 260 children, there were 148 males and 112 females. The follow-up time was 26 (16, 38) months. A total of 28 children (10.8%) were diagnosed with AML-MRC according to the WHO 2016 diagnostic criteria. Compared with non-AML-MRC children, the frequency of PTPN11, RUNX11, SH2B3, MPL and STAG2 mutations was higher in AML-MRC children (25.0% (7/28) vs. 4.3% (10/232), 14.3% (4/28) vs. 3.9% (9/232), 10.7% (3/28) vs. 2.2% (5/232), 10.7% (3/28) vs. 2.2% (5/232), 10.7% (3/28) vs. 0.9% (2/232), all P<0.05). The 2-year overall survival (OS) and events free survival (EFS) rate of 28 AML-MRC children under WHO 2016 diagnostic criteria were worse than those of 232 non-AML-MRC children ((62.1±10.8)% vs. (94.5±1.6)%, χ2=22.1 ,P<0.001;(48.0±10.6)% vs. (70.9±3.2)%, χ2=6.33, P=0.012). Twenty-seven children (10.4%) were eventually diagnosed with AML-MRC according to WHO 2022 criteria, their 2-year OS rate were worse than 233 non-AML-MRC children ((60.8±11.1)% vs. (94.5±1.6)%, χ2=24.49 ,P<0.001), and there was no statistically significant difference in EFS rate between two groups at 2 years ((55.1±10.8)% vs. (70.1±3.2)%, χ2=2.44 , P=0.119). Conclusions:Compared with the 2022 WHO diagnostic criteria, the survival rates of children with AML-MRC under the 2016 WHO diagnostic criteria were worse than that of children without MRC.The new version of the AML-MRC diagnostic criteria emphasizes the importance of genes.

Objective:To investigate the clinical features and prognosis of testicular relapse in pediatric acute lymphoblastic leukemia (ALL).Methods:Clinical data including the age, time from initial diagnosis to recurrence, relapse site, and therapeutic effect of 37 pediatric ALL with testicular relapse and treated in Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences between November 2011 and December 2022 were analyzed retrospectively. Patients were grouped according to different clinical data. Kaplan-Meier analysis was used to evaluate the overall survival (OS) rate and event free survival (EFS) rate for univariate analysis, and Cox proportional-hazards regression model was used to evaluate the influencing factors of OS rate and EFS rate for multivariate analysis.Results:The age at initial diagnosis of 37 pediatric testicular relapse patients was (5±3) years and the time from initial diagnosis to testicular recurrence was (37±15) months. The follow-up time was 43 (22, 56) months. Twenty-three patients (62%) were isolated testis relapse. The 5-year OS rate and EFS rate of the 37 relapsed children were (60±9) % and (50±9) % respectively. Univariate analysis showed that the 2-year EFS rate in the group of patients with time from initial diagnosis to testicular recurrence >28 months was significantly higher than those ≤28 months ((69±10)% vs. (11±11)%, P<0.05), 2-year EFS rate of the isolated testicular relapse group was significantly higher than combined relapse group ((66±11)% vs. (20±13) %, P<0.05), 2-year EFS rate of chimeric antigen receptor T (CAR-T) cell treatment after relapse group was significantly higher than without CAR-T cell treatment after relapse group ((78±10)% vs. (15±10)%, P<0.05). ETV6-RUNX1 was the most common genetic aberration in testicular relapsed ALL (38%, 14/37). The 4-year OS and EFS rate of patients with ETV6-RUNX1 positive were (80±13) % and (64±15) %, respectively. Multivariate analysis identified relapse occurred≤28 months after first diagnosis ( HR=3.09, 95% CI 1.10-8.72), combined relapse ( HR=4.26, 95% CI 1.34-13.52) and CAR-T cell therapy after relapse ( HR=0.15,95% CI 0.05-0.51) were independent prognostic factors for 2-year EFS rate (all P<0.05). Conclusions:The outcome of testicular relapse in pediatric ALL was poor. They mainly occurred 3 years after initial diagnosis. ETV6-RUNX1 is the most common abnormal gene.Patients with ETV6-RUNX1 positive often have a favorable outcome. Early relapse and combined relapse indicate unfavorable prognosis, while CAR-T cell therapy could significantly improve the survival rate of children with testicular recurrence.

Objective:To investigate the clinical characteristics and long-term prognostic factors of relapsed pediatric acute lymphoblastic leukemia (ALL).Methods:Clinical data including the age, time from initial diagnosis to relapse, relapse site, and molecular biological features of 217 relapsed ALL children primarily treated by the Chinese Children's Leukemia Group (CCLG)-ALL 2008 protocol in Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences between April 2008 and April 2015 were collected and analyzed in this retrospective cohort study. Kaplan-Meier analysis was used to evaluate the overall survival (OS) rate and event free survival (EFS) rate for univariate analysis, and Cox proportional-hazards regression model was used to evaluate the influencing factors of OS rate and EFS rate for multivariate analysis.Results:The age at initial diagnosis of 217 relapsed patients was 5 (3, 7) years. There were 135 males and 82 females. The time from initial diagnosis to relapse of 217 children was 22 (10, 39) months. After relapse, 136 out of 217 children (62.7%) received treatment and the follow-up time was 65 (47, 90) months. The 5-year OS rate and EFS rate of the 136 relapsed children were (37±4) % and (26±4) %, respectively. The predicted 10-year OS rate and EFS rate were (35±5) % and (20±4) %, respectively. Univariate analysis showed that the 5-year OS rate in the group of patients with late relapse (43 cases) was significantly higher than those with very early (54 cases) and early relapse (39 cases) ((72±7)% vs. (16±5)%, (28±8)%, χ2=35.91, P<0.05), 5-year OS rate of the isolated extramedullary relapse group (20 cases) was significantly higher than isolated bone marrow relapse group (102 cases) and combined relapse group (14 cases) ((69±11)% vs. (31±5)%, (29±12)%, χ2=9.14, P<0.05), 5-year OS rate of high-risk group (80 cases) was significantly lower than standard-risk group (10 cases) and intermediate-risk group (46 cases) ((20±5)% vs. (90±10)%, (54±8)%, χ2=32.88, P<0.05). ETV6::RUNX1 was the most common fusion gene (13.2%, 18/136). The predicted 10-year OS rate of relapsed children with positive ETV6::RUNX1 was significantly higher than those without ETV6::RUNX1 (118 cases) ((83±9)% vs. (26±5)%, χ2=14.04, P<0.05). The 5-year OS for those accepted hematopoietic stem cell transplantation (HSCT) after relapse (42 cases) was higher than those without HSCT (94 cases) ((56±8)% vs. (27±5)%, χ2=15.18, P<0.05). Multivariate analysis identified very early/early relapse ( HR=3.91, 95% CI 1.96-7.79; HR=4.15, 95% CI 1.99-8.67), bone marrow relapse including isolated bone marrow relapse and combined relapse ( HR=6.50, 95% CI 2.58-16.34; HR=5.19, 95% CI 1.78-15.16), with ETV6::RUNX1 ( HR=0.23, 95% CI 0.07-0.74) and HSCT after relapse ( HR=0.24, 95% CI 0.14-0.43) as independent prognostic factors for OS (all P<0.05). Conclusions:Relapsed pediatric ALL mainly occurs very early and often affects bone marrow, which confer poor outcome. ETV6::RUNX1 is the most common genetic aberration with a favorable outcome. HSCT could rescue the outcome of relapsed children, though the survival rate is still poor.

Minimal residual disease (MRD), a crucial biomarker for assessing efficacy and predicting recurrence, refers to residual tumor cells remaining in the body of patients with hematological malignancies who achieved complete remission after treatment. This study aimed to conduct a retrospective analysis of the clinical diagnosis, treatment, and MRD monitoring of a pediatric patient with multiple acute B-lymphocytic leukemia relapses, alongside a review of relevant literature. In this case, Ig rearrangement based on next-generation sequencing (NGS) was more accurate in assessing the MRD level, compared with the traditional method of MRD detection, indicating the risk of earlier relapse and guided interventions in time. Additionally, NGS-MRD detected clonal evolution, providing new ideas to further investigate the intrinsic factors of disease development.

This case report presents a patient with pediatric acute myeloid leukemia (AML) with RUNX1∷MTG16, admitted to the Blood Disease Hospital of the Chinese Academy of Medical Sciences in October 2023. He was 13 years old, with a chief complaint of fatigue for 20 days. Bone marrow smear revealed 17.0% blasts, the karyotype was 46,XY,t (16; 21) (q24; q22), molecular biology demonstrated RUNX1∷MTG16 fusion gene, combined with FLT3-ITD mutation. The child was diagnosed with AML (with RUNX1 ∷ MTG16). Complete remission was achieved after chemotherapy induction. The induction therapy regimen was mitoxantrone hydrochloride liposomes combined with cytarabine (MA). The RUNX1 ∷ MTG16 and FLT3-ITD were negative after another MA treatment course. However, the RUNX1 ∷ MTG16 and FLT3-ITD were turning positive during the following intensive treatment, and he then successfully underwent matched sibling donor umbilical cord blood transplantation.

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) (χ²=5.410, P=0.020) , while the relapse rates were 29% (9/31) and 38% (12/32) (χ²=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) (χ²=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) (χ²=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) (χ²=9.606, P=0.002), while the 8-year EFS rates were 66% (35/53) and 27% (7/26) (χ²=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.

Objective: To evaluate heterogeneity and clonal evolution in pediatric ETV6-RUNX1⁺ acute lymphoblastic leukemia (ALL) in China. Methods: Totally 48 children (<14 years) with newly diagnosed ETV6-RUNX1⁺ ALL in Institute of Hematology and Blood Disease Hospital, CAMS and PUMC, from February 2006 to June 2011 were included. The copy number variations were analyzed by quantitative multigene fluorescence in situ hybridization (QM-FISH) in 48 patients. Non-normal distribution of measurement data were shown with Median (range) , count data were shown with percent (%) . Overall survival and event-free survival were estimated by the Kaplan-Meier method and compared with the log-rank test. Results: Forty-eight patients were tested by QM-FISH. Of 48 patients, 70.8% harbored one clone, 18.8% two subclones, and 10.4% three or more subclones. The clone heterogeneity was detected by two different models: the linear succession model and the branching evolution model. ETV6-RUNX1⁺ ALL relapse evolved from an ancestral clone or a new clone. The patients relapsed from a new clone got the worse outcome. Conclusion The clone evolution was detected in pediatric ETV6-RUNX1⁺ ALL in China. QM-FISH might be helpful to evaluate the outcome of relapsed patients. A new clone was associated with a poorer outcome.

OBJECTIVETo evaluate the copy number variations (CNVs) in pediatric ETV6/RUNX1 gene positive acute lymphoblastic leukemia(ALL) and its correlation with clinical features and prognosis.

METHODTotally 141 children (<14 years of age) with newly diagnosed ETV6/RUNX1 positive ALL in Institute of Hematology and Blood Diseases Hospital, were included from January 2006 to November 2012. The CNVs were analyzed by multiplex ligation-dependent probe amplification (MLPA). The survival rate between the patients with CNVs were explored. Overall survival (OS) and event-free survival (EFS) were estimated by the Kaplan-Meier method and compared with the log-rank test.

RESULTAmong the 141 cases, 55.3% (n=78) were boys and 44.7% (n=63) were girls and the median age was 4 (1-13) years. The estimated 5-year DFS rate for the patients was (84±4)%. The estimated 5-year OS rate for the patients was (85±4)%. Ninety-five patients were tested MLPA. CNVs were detected in 73 cases (76.8%). CNVs of genes EBF1(15.8%), CDKN2A/2B(18.9%), PAX5(21.1%), ETV6(54.8%), BTG1(10.5%) were detected in more than 10% of the patients. Among the 95 patients, EBF1 deletions were found in 9 patients and EBF1 amplifications were found in 6 patients; 5-year recurrence-free survival (RFS) was statistically significant among 3 groups (χ(2)=9.809, P=0.007) . PAX5 deletions were found in 13 patients and PAX5 amplifications were found in 7 patients; the difference in 5-year RFS was statistically significant between 3 groups(χ(2)=7.622, P=0.022). ETV6 deletions were found in 39 patients and ETV6 amplifications were found in 13 patients; the difference in 5-year RFS was statistically significant among the 3 groups (χ(2)=11.045, P=0.004).

CONCLUSIONThe CNVs had prognostic relevance in ETV6/RUNX1 positive ALL.

Adolescent ; Child ; Core Binding Factor Alpha 2 Subunit ; DNA Copy Number Variations ; Disease-Free Survival ; Humans ; Multiplex Polymerase Chain Reaction ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Prognosis ; Proto-Oncogene Proteins c-ets ; Repressor Proteins ; Survival Rate