Pediatric B-lineage Acute Lymphoblastic Leukemia Research Articles

Healthcare cost and utilization for chimeric antigen receptor (CAR) T-cell therapy in the treatment of pediatric acute lymphoblastic leukemia: A commercial insurance claims database analysis.

B-lineage acute lymphoblastic leukemia (B-ALL) is the most common malignancy of childhood. With the introduction of novel cellular therapies, cost of care is a critical component and the financial burden experienced by patients and society requires evaluation. This study aims to assess the utilization and cost of care for chimeric antigen receptor T-cell (CAR-T) therapy for pediatric ALL patients with commercial insurance coverage in the United States. Using de-identified commercial insurance data from the OptumLabs® Data Warehouse, a cohort of 37 patients, aged 1-25 years, with B-ALL treated with CAR-T therapy between Oct 2016 and Dec 2021 in the United States was identified. Cost was evaluated for a 90 day period encompassing CAR-T infusion and by administration and complication characteristics. Among the 37 identified B-ALL patients that received a CAR-T product infusion, 14 patients were female, median age at administration was 13 years. The median 90-day total cost was $620,500 (Mean: $589,108). Inpatient cost accounted for approximately 71% of the total cost with an average of 28 inpatient days per patient. Although inpatient cost was slightly higher in the older age group (aged 10-25 years) and in patients with a code for cytokine release syndrome (CRS), these differences were not statistically significant. This real-world cost analysis shows for the first time the encompassing cost of CAR-T therapy for pediatric B-ALL patients in the US with commercial insurance. This study provides a valuable benchmark that can be used to analyze the financial implications of CAR-T therapy for pediatric B-ALL therapy on health systems.

Chromatin accessibility landscape of relapsed pediatric B-lineage acute lymphoblastic leukemia

For around half of the pediatric B-lineage acute lymphoblastic leukemia (B-ALL) patients, the molecular mechanism of relapse remains unclear. To fill this gap in knowledge, here we characterize the chromatin accessibility landscape in pediatric relapsed B-ALL. We observe rewired accessible chromatin regions (ACRs) associated with transcription dysregulation in leukemia cells as compared with normal B-cell progenitors. We show that over a quarter of the ACRs in B-ALL are in quiescent regions with high heterogeneity among B-ALLs. We identify subtype-specific and allele-imbalanced chromatin accessibility by integrating multi-omics data. By characterizing the differential ACRs between diagnosis and relapse in B-ALL, we identify alterations in chromatin accessibility during drug treatment. Further analysis of ACRs associated with relapse free survival leads to the identification of a subgroup of B-ALL which show early relapse. These data provide an advanced and integrative portrait of the importance of chromatin accessibility alterations in tumorigenesis and drug responses.

In vivo activity of the dual SYK/FLT3 inhibitor TAK-659 against pediatric acute lymphoblastic leukemia xenografts.

While children with acute lymphoblastic leukemia (ALL) experience close to a 90% likelihood of cure, the outcome for certain high-risk pediatric ALL subtypes remains dismal. Spleen tyrosine kinase (SYK) is a prominent cytosolic nonreceptor tyrosine kinase in pediatric B-lineage ALL (B-ALL). Activating mutations or overexpression of Fms-related receptor tyrosine kinase 3 (FLT3) are associated with poor outcome in hematological malignancies. TAK-659 (mivavotinib) is a dual SYK/FLT3 reversible inhibitor, which has been clinically evaluated in several other hematological malignancies. Here, we investigate the in vivo efficacy of TAK-659 against pediatric ALL patient-derived xenografts (PDXs). SYK and FLT3mRNA expression was quantified by RNA-seq. PDX engraftment and drug responses in NSG mice were evaluated by enumerating the proportion of human CD45+ cells (%huCD45+ ) in the peripheral blood. TAK-659 was administered per oral at 60mg/kg daily for 21 days. Events were defined as %huCD45+ ≥ 25%. In addition, mice were humanely killed to assess leukemia infiltration in the spleen and bone marrow (BM). Drug efficacy was assessed by event-free survival and stringent objective response measures. FLT3 and SYK mRNA expression was significantly higher in B-lineage compared with T-lineage PDXs. TAK-659 was well tolerated and significantly prolonged the time to event in six out of eight PDXs tested. However, only one PDX achieved an objective response. The minimum mean %huCD45+ was significantly reduced in five out of eight PDXs in TAK-659-treated mice compared with vehicle controls. TAK-659 exhibited low to moderate single-agent in vivo activity against pediatric ALL PDXs representative of diverse subtypes.

Intrachromosomal amplification of chromosome 21 in Egyptian pediatric B-lineage acute lymphoblastic leukemia: a hospital-based observational study

Abstract Objective This study was conducted to evaluate the clinicopathologic features as well as the association between the intrachromosomal amplification of chromosome 21 (iAMP21) and the clinical outcome in Egyptian patients with B-cell acute lymphoblastic leukemia (B-ALL) attending/admitted in the Department of Pediatric Oncology of our university hospital. Patients and methods This was a prospective study conducted on 25 newly diagnosed and five relapsed pediatric patients with B-ALL (23 males and seven females), with a mean age of 7.76 ± 5.11 years. Bone marrow aspiration was done to diagnose and evaluate remission of participants, and fluorescence in situ hybridization (FISH) analysis using the ETV6-RUNX1 probes was used to detect RUNX1 amplification. Results iAMP21 was identified in 28% of newly diagnosed patients with B-ALL and in 80% of relapsed cases with B-ALL. There was a significant association between positive iAMP21 cases and failure to attain complete remission at day 28 (P=0.004). A significant relationship among the 14 patients monitored for disease outcome was found between the presence of iAMP21 and occurrence of relapse or death in newly diagnosed, or failure to achieve complete remission or death in relapsed cases (P=0.036). Conclusion There was a higher incidence of iAMP21 among our Egyptian pediatric B-ALL cases and unfavorable effect of iAMP21 on patients’ prognosis even with coexistence of ETV6-RUNX1.

Safety and efficacy of co-administration of CD19 and CD22 CAR-T cells in children with B-ALL relapse after CD19 CAR-T therapy

BackgroundCD19-targeted chimeric antigen receptor T-cell (CAR-T) therapy has shown remarkable efficacy in treating relapsed or refractory pediatric B-lineage acute lymphoblastic leukemia (B-ALL). However, poor results are obtained when the same product is reused in patients who relapse after CAR-T. Therefore, there is a need to explore the safety and efficacy of co-administration of CD19- and CD22-targeted CAR-T as a salvage second CAR-T therapy (CART2) in B-ALL patients who relapse after their first CD19 CAR-T treatment (CART1).MethodsIn this study, we recruited five patients who relapsed after CD19-targeted CAR-T. CD19- and CD22-CAR lentivirus-transfected T cells were cultured separately and mixed before infusion in an approximate ratio of 1:1. The total dose range of CD19 and CD22 CAR-T was 4.3 × 106–1.5 × 107/kg. Throughout the trial, we evaluated the patients’ clinical responses, side effects, and the expansion and persistence of CAR-T cells.ResultsAfter CART2, all five patients had minimal residual disease (MRD)-negative complete remission (CR). The 6- and 12-month overall survival (OS) rates were 100%. The median follow-up time was 26.3 months. Three of the five patients bridged to consolidated allogeneic hematopoietic stem cell transplantation (allo-HSCT) after CART2 and remained in MRD-negative CR at the cut-off time. In patient No. 3 (pt03), CAR-T cells were still detected in the peripheral blood (PB) at 347 days post-CART2. Cytokine release syndrome (CRS) only occurred with a grade of ≤ 2, and no patients experienced symptoms of neurologic toxicity during CART2.ConclusionsMixed infusion of CD19- and CD22-targeted CAR-T cells is a safe and effective regimen for children with B-ALL who relapse after prior CD19-targeted CAR-T therapy. Salvage CART2 provides an opportunity for bridging to transplantation and long-term survival.Trial registration: Chinese Clinical Trial Registry, ChiCTR2000032211. Retrospectively registered: April 23, 2020.

Hyperactive CREB subpopulations increase during therapy in pediatric B-lineage acute lymphoblastic leukemia.

Persistence of residual disease in acute lymphoblastic leukemia (ALL) during the initial stages of chemotherapy is associated with inferior survival. To better understand clonal evolution and mechanisms of chemoresistance, we used multiparameter mass cytometry, at single-cell resolution, to functionally characterize pediatric B-ALL cells at disease presentation and those persisting during induction therapy. Analysis of ALL cells from presentation samples (n=42) showed that the most abundant phosphosignals were pCREB, pH2AX and pHH3 and we identified JAK-STAT and RAS pathway activation in five of six patients with JAK or RAS genetic aberrations. The clonal composition of ALL was heterogeneous and dynamic during treatment but all viable cell clusters showed pCREB activation. Levels of pCREB in ALL cells were increased or maintained during therapy and high dimensional analysis revealed a subpopulation of ALL cells at presentation that was positive for pCREB/pHH3/pS6 which increased during treatment in some patients, implicating this signaling node in conferring a survival advantage to multi-agent induction therapy. The small molecule CREB inhibitor, 666-15, was shown to reduce CREB transcriptional activity and induce apoptosis in ALL patient-derived xenograft cells of varying cytogenetic subtypes in vitro, both in the presence and absence of stromal support. Together, these data suggest that the cAMP signaling pathway may provide an opportunity for minimal residual disease-directed therapy for many patients at high risk of relapse.

Indication and selection of pediatric patients for genetically modified T cells

The use of CAR-T cells will completely change the treatment of many hematological diseases, including relapsed pediatric B-lineage acute lymphoblastic leukemia. This article is part of the Brazilian Society of Bone Marrow Transplantation (SBTMO)’s “Technical manual of cellular therapy” to guide physicians to select patients and indicate the use of the CAR-T cells in pediatric patients with acute lymphoblastic leukemia. Other aspects of CAR-T cell therapy and management of important toxicities are included on other articles of this volume.

The Cost of Cellular Therapy in the Treatment of Pediatric Acute Lymphoblastic Leukemia: A Commercial Insurance Claims Database Analysis

Introduction Acute lymphoblastic leukemia (ALL) is the most common malignancy of childhood, with a current incidence across all age groups of approximately 5,000 cases annually in the US and about 7,000 in Europe. Approximately 60% of cases are diagnosed in patients <20 years of age and approximately 85% of pediatric ALL derives from B-cell lineage. In the last decade, the introduction of cellular therapies in pediatric B-lineage ALL has changed the landscape of management, particularly for relapsed/refractory disease. Chimeric antigen receptor T-cell (CAR-T) based approaches allow the engineering of autologous patient T cells to specifically target and destroy tumor cells in a major histocompatibility complex (MHC)-independent manner. With the introduction of these novel therapies for ALL, cost of care is a critical component and financial toxicity experienced by patients and society requires evaluation. Methods Using de-identified commercial insurance data from the Optum Labs Data Warehouse, a cohort of 37 patients, aged 1-25 years, with ALL who received CAR-T therapy was identified, with a CAR-T product administration code between Oct 2016 and Dec 2021 in the United States. ALL diagnosis was confirmed based on ICD-9 and ICD-10 diagnostic codes, in combination with CPT codes for CAR-T administration. Mean and median cumulative costs were computed for a 90 day period, including 30 days prior to product administration, to avoid the variation of bridging therapies, and 60 days following CAR-T administration. Cost was further evaluated by the type and location of service provided, the presence of complication codes for cytokine release syndrome (CRS) and/or immune effector cell-associated neurotoxicity syndrome (ICANS). Results were stratified by age group (1-9 years vs. 10-25 years) as a proxy for upfront ALL risk group. Total cost was also evaluated based on outpatient vs. inpatient CAR-T administration. Results Among the 37 identified ALL patients that received a CAR-T product infusion (1-9 years, 13; 10-25 years, 24), 14 patients were female, 37.8% were White, median age at administration was 13 years (interquartile range 7-19 years) and 35 of 37 enrolled patients had continuous coverage enrollment from one month prior to infusion through two months post-infusion. Mean 90-day total cost of care was $585,398.10 (Median: $620,500.40). Inpatient cost accounted for approximately 71% of the total cost. Although inpatient cost was slightly higher in the older age group and in patients with a code for CRS, these differences were not statistically significant (Figure 1 & 2). No patients in the dataset had a diagnostic code for ICANS. Six patients died during the 60 days post-infusion. Conclusions This robust real-world cost analysis shows for the first time the true cost of CAR-T therapy for pediatric ALL - encompassing not only the cost of the cellular therapy product itself, but the care involved in providing it. We showed that the cost of care is not significantly impacted by patient age or the incidence of CRS. Mean total cost well exceeded $500,000 US dollars, as expected with the listed commercial price of tisagenlecleucel of $475,000. This study provides a valuable benchmark that can be used to analyze the financial toxicity of CAR-T therapy for pediatric ALL therapy on health systems, patients and families. The cost of this therapy can be re-assessed over time as other novel therapeutics are introduced into ALL therapy and long-term outcome data for this therapy are established. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Blinatumomab for treating pediatric B-lineage acute lymphoblastic leukemia: A retrospective real-world study.

Blinatumomab was shown to be safe and effective for consolidation therapy in B-cell acute lymphoblastic leukemia (B-ALL). This study aimed to investigate the effectiveness and safety of blinatumomab in pediatric B-ALL patients in a real-world setting. This was a retrospective, observational study that included patients who initiated blinatumomab treatment between October 1, 2020 and June 20, 2022. Patients with B-ALL diagnosis, age below 18 years, and at least one blinatumomab treatment cycle were included. Treatment-related toxicities were assessed. Totally 23 pediatric patients were included in this study, with a median age of 6 years (range, 2 to 11 years). Blinatumomab therapy was applied for MRD-positive (disease ≥0.01%, n = 3) or chemotherapy-ineligible (n = 20) B-ALL cases. The median follow-up time was 9 months, and all evaluable patients achieved complete molecular remission with undetectable MRD. Four relapsed B-ALL cases proceeded to hematopoietic stem cell transplantation (HSCT) without further bridging therapy, while the others underwent maintenance chemotherapy after blinatumomab treatment. Grade ≥3 febrile neutropenia, white blood cell decrease and seizure were observed in 57%, 48% and 4.3% of patients, respectively. One case discontinued therapy due to neurologic toxicities. Elevated cytokine levels were observed in 4 patients. In all 23 patients, increased T-cell and low B-cell counts (<10/μl) were detected during blinatumomab therapy. These encouraging results suggest blinatumomab in pediatric B-ALL patients with MRD+ or chemotherapy-related toxicities is effective and safe in the short run, although long-term follow-up is still needed.

Outcomes of Anti-CD19 CAR-T Treatment of Pediatric B-ALL with Bone Marrow and Extramedullary Relapse.

PurposeAnti-CD19 chimeric antigen receptor T-cell (19CAR-T) immunotherapy has achieved impressive clinical results in adult and pediatric relapsed/refractory (r/r) B-lineage acute lymphoblastic leukemia (B-ALL). However, the application and effect of CAR-T therapy in B-ALL patients with extramedullary relapse are rarely issued even disqualified in some clinical trials. Here, we examined the efficacy of 19CAR-T in patients with both bone marrow and extramedullary involvement.Materials and MethodsCAR-T cells were generated by transfection of primary human T lymphocytes with a lentiviral vector expressing anti-CD19 single-chain antibody fragments with the cytoplasmic domains of 4-1BB and CD3ζ, and used to infuse patients diagnosed as having r/r B-ALL with extramedullary origination. Clinical responses were evaluated by the use of bone marrow aspiration, imaging, and flow cytometry.ResultsEight patients received 19CAR-T infusion and all attained complete remission (CR). Only one patient was bridged to hematopoietic stem cell transplantation (HSCT). Although three patients relapsed after infusion, they received 19/22CAR-T infusion sequentially and attained a second remission. To date, five patients are in continuous CR and all eight patients are still alive. The mean follow-up time was 21.9 months, while the 24-month estimated event-free survival is 51.4%.Conclusion19CAR-T therapy can lead to clinical remission for extramedullary relapsed pediatric B-ALL patients. However, the problem of CD19+ relapses after CAR-T remained to be solved. For patients relapsing after CAR-T, a second CAR-T therapy creates another opportunity for remission for subsequent HSCT.

Age related gene DST represents an independent prognostic factor for MYCN non-amplified neuroblastoma

BackgroundMYCN amplification and age are two critical prognostic factors of pediatric neuroblastoma. Previously, we had revealed the prognosis of MYCN target genes. However, the prognostic effects of age related genes in neuroblastoma are unclear.MethodsThe prognostic significance of age and MYCN amplification was determined through multivariate cox regression and Kaplan-Meier survival analysis. Genes differentially expressed in MYCN non-amplified younger neuroblastoma patients were identified using Therapeutically Applicable Research to Generate Effective Treatments (TARGET) and Gene Expression Omnibus (GEO) datasets. The prognostic effects of age related genes ALCAM, CACNA2D3, DST, EPB41L4A and KIF1B in pediatric neuroblastoma patients were determined by Kaplan-Meier survival.ResultsIn a pediatric pan-cancer analysis, age was associated with the overall survival of pediatric B-lineage acute lymphoblastic leukemia, neuroblastoma and wilms tumor in TARGET dataset. Moreover, the prognostic effects of age in neuroblastoma were validated using two independent neuroblastoma cohorts. Furthermore, age and MYCN amplification were independent prognostic factors in pediatric neuroblastoma. Compared with MYCN non-amplified older neuroblastoma patients, MYCN non-amplified younger neuroblastoma patients had better clinical outcomes. ALCAM, CACNA2D3, DST, EPB41L4A and KIF1B were highly expressed in MYCN non-amplified younger neuroblastoma patients. And the higher expression levels of ALCAM, CACNA2D3, DST, EPB41L4A or KIF1B were associated with better prognosis of MYCN non-amplified neuroblastoma patients. DST was an independent prognostic factor in MYCN non-amplified neuroblastoma patients and MYCN non-amplified neuroblastoma younger patients with higher DST expression levels had the best clinical overall survival.ConclusionsAge related gene DST was an independent prognostic factor in MYCN non-amplified neuroblastoma. MYCN non-amplified younger neuroblastoma patients with higher DST expression levels had the best clinical overall survival.

Prognostic Relevance of Expression of EMP1, CASP1, and NLRP3 Genes in Pediatric B-Lineage Acute Lymphoblastic Leukemia.

Glucocorticoid (GC), such as prednisolone, is an essential component of multidrug chemotherapy regimen for pediatric acute lymphoblastic leukemia (ALL). Resistance to GC in leukemia cells is associated with disease progression and poor prognosis. Despite the extensive use of GC for many years, molecular mechanisms underlying its resistance in ALL have not been fully uncovered. Recent studies have shown a potential role of EMP1, CASP1, and NLRP3 genes in prednisolone response. In this study on 148 pediatric B-ALL patients, we studied these three genes to assess their association with prednisolone response measured by day 8 blast count after 7 days of induction therapy with prednisolone. Intriguingly, ALL samples exhibited higher expression of EMP1 along with a low expression of CASP1 and NLRP3 compared to disease free normal bone marrow collected from patients with solid tumors. Among the three analyzed genes, only EMP1 was found to be overexpressed in prednisolone poor responders (p=0.015). Further, a comparison of gene expression between cytogenetic subtypes revealed higher expression of EMP1 in BCR-ABL subtype. Expression of EMP1 in multiple gene expression datasets was used for gene set enrichment analysis, which revealed TNF-α, IL-2-STAT5 signaling, inflammatory responses and hypoxia as the major positively associated pathways and E2F targets as negatively associated pathways. Interestingly, the clinical remission rate was higher in CASP1 high patients (p=0.048). In univariate survival analysis, higher EMP1 expression was associated with poor prognostic measures while higher expression of NLRP3 and CASP1 was associated with better prognostic measures in our data. Further, multivariate analysis revealed an independent association of high CASP1 and NLRP3 with a better prognosis. This study strengthens the available evidence that mRNA expression of EMP1, CASP1, and NLRP3 may serve as potential biomarkers for risk stratification of pediatric B-ALL patients.

Droplet Digital PCR Improves IG-/TR-based MRD Risk Definition in Childhood B-cell Precursor Acute Lymphoblastic Leukemia.

Minimal residual disease (MRD) is the most powerful prognostic factor in pediatric acute lymphoblastic leukemia (ALL). Real-time quantitative polymerase chain reaction (RQ-PCR) represents the gold standard for molecular MRD assessment and risk-based stratification of front-line treatment. In the protocols of the Italian Association of Pediatric Hematology and Oncology (AIEOP) and the Berlin-Frankfurth-Munschen (BFM) group AIEOP-BFM ALL2009 and ALL2017, B-lineage ALL patients with high RQ-PCR-MRD at day+33 and positive at day+78 are defined slow early responders (SERs). Based on results of the AIEOP-BFM ALL2000 study, these patients are treated as high-risk also when positive MRD signal at day +78 is below the lower limit of quantification of RQ-PCR (“positive not-quantifiable,” POS-NQ). To assess whether droplet digital polymerase chain reaction (ddPCR) could improve patients’ risk definition, we analyzed MRD in 209 pediatric B-lineage ALL cases classified by RQ-PCR as POS-NQ and/or negative (NEG) at days +33 and/or +78 in the AIEOP-BFM ALL2000 trial. ddPCR MRD analysis was performed on 45 samples collected at day +78 from SER patients, who had RQ-PCR MRD ≥ 5.0 × 10–4 at day+33 and POS-NQ at day+78 and were treated as medium risk (MR). The analysis identified 13 of 45 positive quantifiable cases. Most relapses occurred in this patients’ subgroup, while ddPCR NEG or ddPCR-POS-NQ patients had a significantly better outcome (P < 0.001). Overall, in 112 MR cases and 52 standard-risk patients, MRD negativity and POS-NQ were confirmed by the ddPCR analysis except for a minority of cases, for whom no differences in outcome were registered. These data indicate that ddPCR is more accurate than RQ-PCR in the measurement of MRD, particularly in late follow-up time points, and may thus allow improving patients’ stratification in ALL protocols.

Copy Number Alterations are Associated with the Risk of Very Early Relapse in Pediatric B-lineage Acute Lymphoblastic Leukemia: A Nested Case-control MIGICCL Study

Refining risk stratification to avoid very early relapses (VER) in Mexican patients with B-lineage acute lymphoblastic leukemia (B-ALL) could lead to better survival rates in our population. The purpose of this study was to investigate the association between the United Kingdom ALL (UKALL)-CNA classifier and VER risk in Mexican patients with childhood B-ALL. A nested case-control study of 25 cases with VER and 38 frequency-matched controls without relapse was conducted within the MIGICCL study cohort. They were grouped into the categories of the UKALL-CNA risk classifier (good [reference], intermediate and poor), according to the results obtained by multiplex ligation dependent probe amplification. Overall and disease-free survival (DFS) were estimated using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards analyses were conducted. The CDKN2A/B genes were most frequently deleted in the group with relapse. According to UKALL-CNA classifier, 33 (52.4%) patients were classified as good, 21 (33.3%) intermediate and 9 (14.3%) poor-risk B-ALL. The intermediate and poor risk groups were associated with an increased risk of VER (HR=4.94, 95% CI=1.87-13.07 and HR=7.42, 95% CI=2.37-23.26, respectively) in comparison to the good-risk patients. After adjusting by NCI risk classification and chemotherapy scheme in a multivariate model, the risks remained significant. Our data support the clinical utility of profiling CNAs to potentially refine current risk stratification strategies of patients with B-ALL.

Clinical significance of minimal residual disease in B-lineage acute lymphoblastic leukemia pediatric patients with different fusion gene backgrounds

Objective To study the clinical significance of minimal residual disease (MRD) in B-lineage acute lymphoblastic leukemia (B-ALL) pediatric patients with different fusion gene backgrounds. Methods A retrospective analysis was performed on the medical data of 441 B-ALL children who were treated from January 2008 to April 2015. Among the 441 children, 336 had negative fusion gene, 79 had positive ETV6-RUNX1 fusion gene, and 26 had positive E2A-PBX1 fusion gene. Flow cytometry was used to detect MRD, and the influence of MRD on day 15 (TP1), day 33 (TP2), and week 12 (TP3) of induction therapy on prognosis was analyzed. Results In patients with negative fusion gene, the positive MRD group had significantly lower overall survival (OS) rate and event-free survival (EFS) rate (P 0.05). Conclusions MRD has the most definite prognostic significance in pediatric B-ALL patients with negative fusion gene, while it has unsatisfactory prognostic significance in those with positive ETV6-RUNX1 or positive E2A-PBX1.

Prognostic Impact of Somatic Copy Number Alterations in Childhood B-Lineage Acute Lymphoblastic Leukemia.

The high prevalence of relapse in pediatric B-lineage acute lymphoblastic leukemia (B-ALL) despite the improvements achieved using current risk stratification schemes, demands more accurate methods for outcome prediction. Here, we provide a concise overview about the key advances that have expanded our knowledge regarding the somatic defects across B-ALL genomes, particularly focusing on copy number alterations (CNAs) and their prognostic impact. The identification of commonly altered genes in B-ALL has inspired the development of risk classifiers based on copy number states such as the IKZF1plus and the United Kingdom (UK) ALL-CNA classifiers to improve outcome prediction in B-ALL. CNA-risk classifiers have emerged as effective tools to predict disease relapse; though, their clinical applications are yet to be transferred to routine practice.

A Case Report and Review of B‑Lineage Acute Lymphoblastic Leukemias with Cannibalistic Lymphoblasts: A Unique Morphologic and Molecular Genetic Entity?

AbstractCannibalism is a type of “cell-in-cell” phenomenon commonly described in myeloid lineage malignancies. Although lymphocytes and their precursors are inherently non-phagocytic, there are sporadic case reports describing cannibalism by leukemic lymphoblasts. In the current manuscript, we report the case of a pediatric B-lineage acute lymphoblastic leukemia (B-ALL) patient showing cannibalistic lymphoblasts and have reviewed the clinical and laboratory characteristics of similar cases documented in literature. Our manuscript highlights that all reported B-ALL patients showing cannibalistic lymphoblasts had intra-cytoplasmic vacuolations, and all such treatment-naïve pediatric patients were ETV6-RUNX1 fusion positive and had aberrant expression of myeloid lineage antigens.

Demographic features of pediatric B-ALL (B Lineage Acute Lymphoblastic Leukemia) patients in Pakistani population.

Objectives: This study was conducted to evaluate demographic features of pediatric B-ALL patients in Pakistani population and their prognosis in a Tertiary Care Hospital. Study Design: Descriptive study. Setting: Department of Pathology Tertiary Care Children Hospital, Lahore. Period: 1st January 2016 to 31st December 2016. Material &amp; Methods: A total of 66 samples of newly diagnosed B-ALL patients (aged 1-15 years) were taken for study. For diagnosis of B-ALL, bone marrow aspiration, cytochemical staining, immunophenotyping was done. Results: Out of 66 B-ALL patients, 35 (53%) were males and 31 (47%) were females. The median age for pediatric ALL subjects was 5 years. Out of 66 B-ALL patients, 39 (59%) were in standard risk group. The prognosis of ALL patients in our study was poor as compared with international statistics with 12/21 deaths (57%) in standard risk group. Also, history of consanguinity of parents was significantly high in dead patients (p = 0.013). Deaths were also comparatively more in males than in females. Conclusion: The prognosis of pediatric B-ALL patients in our study was poor as compared with international statistics because of multifactorial reasons. Strategies are needed to be adopted to improve the outcome of B-ALL patients in our population.

Evaluation of CD304 expression in pediatric Blineage acute lymphoblastic leukemia

BACKGROUND: Acute lymphoblastic leukemia is the most common form of cancer (25–30%) and predominant subtype of leukemia (75–80%) in children. However, childhood ALL has considerable phenotypic and genotypic heterogeneity, which is of diagnostic and prognostic importance. CD304 is a transmembrane glycoprotein C-type lectin found on plasmacytoid dendritic cells, It acts as a receptor for class III semaphorins mediating neuronal guidance and axonal growth.Aim of the study: to study expression of CD304 in de novo newly diagnosed pediatric B- lineage ALL patients and to evaluate its association with hematological and clinical parameters.Patients and methods: This cross sectional study was conducted on 30 pediatric patients with de novo newly diagnosed BALL randomly selected in relation to sex included (16 males and 14females) with their age ranging 1-14 year.RESULTS: This study revealed that CD304 was detected in (56.67%) of newly diagnosed B-ALL patients and (43.33%) of them were negative for CD304 expression. It was detected that CD304 was not associated with age, gender, clinical presentations, other prognostic hematological parameters (Hb, WBC count, platelate count), blast percentage, NCI risk, B-ALL subtype, positive PAS and response to induction therapy.CONCLUSIONS: CD304 expression was independent on the hematological and physical characteristics of patients, since the majority of positive CD304B-ALL cases were in high risk groups of NCI criteria and 60% of non- responder were positive CD304. PAS stain was detected in standard risk groups of NCI criteria, common B-ALL subtype and response to induction therapy.

Leukemia-induced dysfunctional TIM-3+CD4+ bone marrow T cells increase risk of relapse in pediatric B-precursor ALL patients.

Interaction of malignancies with tissue-specific immune cells has gained interest for prognosis and intervention of emerging immunotherapies. We analyzed bone marrow T cells (bmT) as tumor-infiltrating lymphocytes in pediatric precursor-B cell acute lymphoblastic leukemia (ALL). Based on data from 100 patients, we show that ALL is associated with late-stage CD4+ phenotype and loss of early CD8+ T cells. The inhibitory exhaustion marker TIM-3 on CD4+ bmT increased relapse risk (RFS = 94.6/70.3%) confirmed by multivariate analysis. The hazard ratio of TIM-3 expression nearly reached the hazard ratio of MRD (7.1 vs. 8.0) indicating that patients with a high frequency of TIM-3+CD4+ bone marrow T cells at initial diagnosis have a 7.1-fold increased risk to develop ALL relapse. Comparison of wild type primary T cells to CRISPR/Cas9-mediated TIM-3 knockout and TIM-3 overexpression confirmed the negative effect of TIM-3 on T cell responses against ALL. TIM-3+CD4+ bmT are increased in ALL overexpressing CD200, that leads to dysfunctional antileukemic T cell responses. In conclusion, TIM-3-mediated interaction between bmT and leukemia cells is shown as a strong risk factor for relapse in pediatric B-lineage ALL. CD200/TIM-3-signaling, rather than PD-1/PD-L1, is uncovered as a mechanism of T cell dysfunction in ALL with major implication for future immunotherapies.