Uniform approach to risk classification and treatment assignment for children with acute lymphoblastic leukemia

Isolated late testicular relapse of B-cell acute lymphoblastic leukemia treated with intensive systemic chemotherapy and response-based testicular radiation: A Children's Oncology Group study

BACKGROUND

The incidence of isolated testicular relapse (ITR) of acute lymphoblastic leukemia (ALL) has decreased with contemporary treatment strategies, but outcomes are suboptimal with a 58% 5-year overall survival (OS). This study aimed to improve outcome in patients with ITR of B-cell ALL (B-ALL) occurring after 18 months of first clinical remission using intensive systemic chemotherapy and to decrease long-term sequelae by limiting use of testicular radiation.

PROCEDURE

Forty patients in first ITR of B-ALL were enrolled. Induction (dexamethasone, vincristine, daunorubicin, and intrathecal triple therapy) was preceded by one dose of high-dose methotrexate (MTX, 5 g/m² ). Following induction, 25 of 26 patients who had persistent testicular enlargement underwent testicular biopsy. Eleven had biopsy-proven disease and received bilateral testicular radiation (24 Gy), whereas twenty-nine did not.

RESULTS

Overall 5-year event-free survival (EFS)/OS was 65.0 ± 8.8%/73.1 ± 8.3%, with 5-year EFS 62.1 ± 11.0% vs. 72.7 ± 14.4% for patients who did not receive radiation therapy (XRT) (n = 29) compared with those who did (n = 11), respectively (P = 0.64). There were six second bone marrow relapses and six second ITRs. The proportion of second relapses was similar in the patients that received testicular radiation and those who did not. However, the 5-year OS was similar for patients who did not receive XRT (72.6 ± 10.2%) compared with those who did (72.7 ± 14.4%) (P = 0.85).

CONCLUSIONS

A 5-year OS rate of 73.1 ± 8.3% was obtained in children with first ITR of B-ALL occurring after 18 months of CR1 (length of first clinical remission) using intensive chemotherapy and limiting testicular radiation.

Treatment outcome of pediatric acute lymphoblastic leukemia in Yeungnam region: Multicenter retrospective study of Study Alliance of Yeungnam Pediatric Hematology-Oncology (SAYPH)

OBJECTIVES

We aimed to evaluate treatment outcomes of pediatric acute lymphoblastic leukemia (ALL) subgroups by risk-stratification, in the Yeungnam region of Korea.

METHODS

We reviewed the courses of 409 newly diagnosed ALL patients from January 2004 to December 2013 in the Yeungnam region.

RESULTS

All patients were classified into three risk groups: standard risk (SR, n=212), high risk (HR, n=153) and very high risk (VHR, n=44). The mean follow-up time was 73.6 ± 39.4 months. The 7-year event-free survival (EFS) and overall survival (OS) rates were 78.7 ± 2.1% and 86.8 ± 1.8%, respectively. Significant 7-year EFS and OS rates for SR (84.0 ± 2.7%, 93.7 ± 1.8%), HR (76.5 ± 3.5%, 82.1 ± 3.3%), and VHR (60.6 ± 7.5%, 69.9 ± 7.5%) were observed (P<0.001), respectively. Relapse occurred in 52 patients, and the cumulative 7-year incidence of relapse differed according to risk groups (SR vs. HR vs. VHR=12.6% vs. 14.0% vs. 29.6%, P=0.003).For the 46 relapsed patients who were treated, the 3-year EFS and OS were 42.3 ± 8.3%and 46.4± 8.4%. Among the 44 VHR patients, EFS was not significantly different between the chemotherapy-treated patients and those received hematopoietic stem cell transplantation (P=0.533). The 7-year EFS of the hyperleukocytosis subgroup (24 cases, 14 under 10 years of age)showed a tendency for better prognosis than that of the other VHR subgroups (P=0.178).

CONCLUSION

Our results revealed improved outcomes in pediatric ALL patients with risk-stratified therapy. The hyperleukocytosis subgroup without any combined chromosomal abnormalities may respond favorably to chemotherapy alone after first complete remission.

Declines Noted in Cognitive Processes and Association With Achievement Among Children With Leukemia

PURPOSE/OBJECTIVES

To assess change in specific cognitive processes during treatment with chemotherapy only among children with acute lymphoblastic leukemia (ALL). 
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DESIGN

A prospective, repeated measures design.
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SETTING

Pediatric oncology treatment centers at Banner-University Medical Center Tucson/Banner Children's-Diamond Medical Center (University of Arizona) and Texas Children's Cancer and Hematology centers (Baylor College of Medicine) in Houston. 
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SAMPLE

71 children with ALL, with a mean age of 6.18 years at the time of diagnosis. 
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METHODS

Using mixed-effects latent growth curve modeling with time since diagnosis as a fixed effect, age-adjusted standardized measures of working memory, processing speed, executive function, and attention were obtained and repeated about one and two years later. A subsample was tested for academic achievement at the end of treatment.
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MAIN RESEARCH VARIABLES

Verbal working memory, visual spatial memory, processing speed, academic achievement, age, and gender. 
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FINDINGS

A significant main effect was observed for age at diagnosis on decline in verbal working memory during treatment. Planned contrasts revealed greater decline among children who were diagnosed when aged younger than five years compared to those diagnosed when aged five years or older. Decline in verbal working memory and achievement in letter-word identification and calculation skills were associated, and decline in spatial memory was associated with calculation. A main effect of gender was observed on processing speed, with female patients showing greater decline than male patients. 
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CONCLUSIONS

Findings from this study may guide the timing of interventions that could improve school achievement among survivors. 
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IMPLICATIONS FOR NURSING

Children undergoing treatment for ALL may experience issues with verbal working memory and increased difficulty in school. Nurses are in a position to refer parents and children to school resources for additional academic support.

Retrospective Analysis of Ploidy in Primary Osseous and Extraosseous Ewing Family Tumors in Children

Aims

To restrospectively study the DNA content in a series of childhood Ewing Family Tumors (EFT), and to investigate its prognostic value.

Methods

The study was performed on a series of 27 EFTs (osseous Ewing's sarcoma, 18 cases; extraos-sous Ewing's sarcoma, 2; peripheral neuroepithelioma, 4; Askin Rosai tumors, 3). Ploidy was investigated using both flow cytometry (FCM) and image cytometry (ICM) on tumor cell suspensions from formalin-fixed paraffin-embedded specimens or fresh frozen tissue obtained from the primary tumor at diagnosis.

Results

Ploidy was evaluable by FCM in all cases, and by ICM in 23/27. When fresh frozen tissue and paraffin-embedded samples from the same tumor were available for analysis, they yielded equal results. The rate of agreement between FCM and ICM was 82%. The majority of cases were diploid, and in the present series aneuploidy seemed to be associated with a poor outcome.

Conclusions

These results suggest that aneuploidy could be an indicator of a bad prognosis in EFT; however, the small number of cases precludes any conclusion of statistical value. Larger restrospective studies on ploidy using archival material could be performed and their reliability is supported by the concordance of results from fresh and formalin-fixed tissue.

Genomics and pharmacogenomics of pediatric acute lymphoblastic leukemia

Acute lymphoblastic leukaemia (ALL) is a prevalent form of pediatric cancer that accounts for 70-80% of all leukemias. Genome-based analysis, exome sequencing, transcriptomics and proteomics have provided insight into genetic classification of ALL and helped identify novel subtypes of the disease. B and T cell-based ALL are two well-characterized genomic subtypes, significantly marked by bone marrow disorders, along with mutations in trisomy 21 and T53. The other ALLs include Early T-cell precursor ALL, Philadelphia chromosome-like ALL, Down syndrome-associated ALL and Relapsed ALL. Chromosomal number forms a basis of classification, such as, hypodiploid ALL, near-haploid, low-hypodiploid, high-hypodiploid and hypodiploid-ALL. Advances in therapies targeting ALL have been noteworthy, with significant pre-clinical and clinical studies on drug pharmacokinetics and pharmacodynamics. Methotrexate and 6-mercaptopurine are leading drugs with best demonstrated efficacies against childhood ALL. The drugs in combination, following dose titration, have also been used for maintenance therapy. Methotrexate-polyglutamate is a key metabolite that specifically targets the disease pathogenesis, and 6-thioguanine nucleotides, derived from 6-mercaptopurine, impede replication and transcription processes, inducing cytotoxicity. Additionally, glucocorticoids, asparaginase, anthracycline, vincristine and cytarabine that trans-repress gene expression, deprives cells of asparagine, triggers cell cycle arrest, influences cytochrome-P450 polymorphism and inhibits DNA polymerase, respectively, have been used in chemotherapy in ALL patients. Overall, this review covers the progress in genome technology related to different sub-types of ALL and pharmacokinetics and pharmacodynamics of its medications. It also enlightens adverse effects of current drugs, and emphasizes the necessity of genome-wide association studies for restricting childhood ALL.

Overexpression of dihydrofolate reductase is a factor of poor survival in acute lymphoblastic leukemia

Dihydrofolate reductase (DHFR) has an important function in DNA synthesis and is a target of methotrexate, which is a crucial treatment option for acute lymphoblastic leukemia (ALL). However, the number of studies conducted to date on DHFR expression in childhood ALL is limited. The aim of the present study was to determine whether the expression of DHFR is associated with survival in childhood ALL. The expression of DHFR in 96 children with ALL and 100 control individuals was determined using reverse transcription-quantitative polymerase chain reaction. The results of the present study demonstrated that the expression of DHFR mRNA in children with ALL was significantly increased (P<0.001), compared with that in the control group. In addition, increased levels of DHFR mRNA were observed in patients with B-cell lineage, compared with patients with T-cell lineage ALL (P<0.05). The Kaplan-Meier estimator analysis revealed that children with ALL who exhibited increased levels of DHFR mRNA had a decreased overall survival time (P<0.05). It was observed that certain patient prognostic features (including age, sex, white blood cell count and high DHFR expression), are associated with poor survival (log-rank test, P<0.05). Therefore, the results of the present study indicated that DHFR upregulation is a factor for poor survival in ALL.

Agents in Development for Childhood Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) is the most common cancer in childhood. Standard chemotherapy has afforded outstanding outcomes for many patients; however, there remain some sub-groups with high-risk features, refractory disease, and patients that  relapse who have a poor prognosis with conventional treatments. Over the past decade, there have been significant advances in newer treatment options, including improved monoclonal antibody therapies, T cell engagers, and chimeric antigen T-cell receptor products, all of which have changed the landscape for patients who relapse. These are now being introduced more frequently and at earlier stages of therapy. We present a brief overview of the biology and etiology of childhood ALL, treatment strategies currently in use, and discuss some newer strategies and their possible role in the future of ALL therapy for children.

Toxicity associated with intensive postinduction therapy incorporating clofarabine in the very high-risk stratum of patients with newly diagnosed high-risk B-lymphoblastic leukemia: A report from the Children's Oncology Group study AALL1131

BACKGROUND

Children, adolescents, and young adults with very high-risk (VHR) B acute lymphoblastic leukemia (B-ALL) have poor outcomes, and novel therapies are needed for this subgroup. The AALL1131 study evaluated postinduction therapy using cyclophosphamide (CPM), etoposide (ETOP), and clofarabine (CLOF) for patients with VHR B-ALL.

METHODS

Patients who were 1 to 30 years old and had VHR B-ALL received modified Berlin-Frankfurt-Münster therapy after induction and were randomized to 1) CPM, cytarabine, mercaptopurine, vincristine (VCR), and pegaspargase (control arm), 2) CPM, ETOP, VCR, and pegaspargase (experimental arm 1), or 3) CPM, ETOP, CLOF (30 mg/m2 /d × 5), VCR, and pegaspargase (experimental arm 2) during the second half of consolidation and delayed intensification.

RESULTS

The rates of grade 4/5 infections and grade 3/4 pancreatitis were significantly increased in experimental arm 2. The dose of CLOF was, therefore, reduced to 20 mg/m2 /d × 5, and myeloid growth factor was required after CLOF administration. Despite these changes, 4 of 39 patients (10.3%) developed grade 4 infections, with 1 of these patients developing a grade 5 acute kidney injury attributed to CLOF, whereas only 1 of 46 patients (2.2%) in experimental arm 1 developed grade 4 infections, and there were no grade 4/5 infections in the control arm (n = 20). Four patients in experimental arm 2 had prolonged cytopenias for >60 days, whereas none did in the control arm or experimental arm 1. Counts failed to recover for 2 of these patients, one having a grade 5 acute kidney injury and the other removed from protocol therapy; both events occurred 92 days after the start of consolidation part 2.

CONCLUSIONS

In AALL1131, CLOF, administered with CPM and ETOP, was associated with unacceptable toxicity. Cancer 2018;124:1150-9. © 2017 American Cancer Society.

Outcome of children with multiply relapsed B-cell acute lymphoblastic leukemia: a therapeutic advances in childhood leukemia & lymphoma study

The survival of pediatric patients with multiply relapsed and/or refractory (R/R) B-cell acute lymphoblastic leukemia has historically been very poor; however, data are limited in the current era. We conducted a retrospective study to determine the outcome of multiply R/R childhood B-ALL treated at 24 TACL institutions between 2005 and 2013. Patient information, treatment, and response were collected. Prognostic factors influencing the complete remission (CR) rate and event-free survival (EFS) were analyzed. The analytic set included 578 salvage treatment attempts among 325 patients. CR rates (mean ± SE) were 51 ± 4% for patients with bone marrow R/R B-ALL who underwent a second salvage attempt, 37 ± 6% for a third attempt, and 31 ± 6% for the fourth through eighth attempts combined. For patients achieving a CR after their second, third, and fourth through eighth attempts, the 2 year EFS was 41 ± 6%, 13 ± 7%, and 27 ± 13% respectively. Our results showed slight improvement when compared to previous studies. This is the largest and most recent study to date that evaluates the outcome of this patient population. Our data will provide detailed reference for the evaluation of new agents being developed for childhood B-ALL.

Single-cell developmental classification of B cell precursor acute lymphoblastic leukemia at diagnosis reveals predictors of relapse

Insight into the cancer cell populations that are responsible for relapsed disease is needed to improve outcomes. Here we report a single-cell-based study of B cell precursor acute lymphoblastic leukemia at diagnosis that reveals hidden developmentally dependent cell signaling states that are uniquely associated with relapse. By using mass cytometry we simultaneously quantified 35 proteins involved in B cell development in 60 primary diagnostic samples. Each leukemia cell was then matched to its nearest healthy B cell population by a developmental classifier that operated at the single-cell level. Machine learning identified six features of expanded leukemic populations that were sufficient to predict patient relapse at diagnosis. These features implicated the pro-BII subpopulation of B cells with activated mTOR signaling, and the pre-BI subpopulation of B cells with activated and unresponsive pre-B cell receptor signaling, to be associated with relapse. This model, termed 'developmentally dependent predictor of relapse' (DDPR), significantly improves currently established risk stratification methods. DDPR features exist at diagnosis and persist at relapse. By leveraging a data-driven approach, we demonstrate the predictive value of single-cell 'omics' for patient stratification in a translational setting and provide a framework for its application to human cancer.

Impact of age on the survival of pediatric leukemia: an analysis of 15083 children in the SEER database

BACKGROUND & AIMS

Age at diagnosis is a key factor for predicting the prognosis of pediatric leukemia especially regarding the survivorship assessment. In this study, we aimed to assess the impact of this prognostic factor such as age in children with pediatric leukemia.

METHODS

In this study, Surveillance, Epidemiology, and End Results Program-registered children with leukemia during 1988-2013 were analyzed. All patients were divided into five groups according to the age at the time of diagnosis (<1, 1-4, 5-9, 10-15, >15 years old). Kaplan-Meier and multivariable Cox regression models were used to evaluate leukemia survival outcomes and risk factors.

RESULTS

There was significant variability in pediatric leukemia survival by age at diagnosis including ALL, AML and CML subtypes. According to the survival curves in each group, survival rate were peaked among children diagnosed at 1–4 years and steadily declined among those diagnosed at older ages in children with ALL. Infants (<1 year) had the lowest survivorship in children with either ALL or AML. However, children (1-4 years) harbored the worst prognosis suffering from CML. A stratified analysis of the effect of age at diagnosis was validated as independent predictors for the prognosis of pediatric leukemia.

CONCLUSIONS

Age at diagnosis remained to be a crucial determinant of the survival variability of pediatric leukemia patients.

Comparison of conventional cytomorphology, flow cytometry immunophenotyping, and automated cell counting of CSF for detection of CNS involvement in acute lymphoblastic leukemia

BACKGROUND AND OBJECTIVE

Cytospin conventional cytomorphology (CCC) is the standard method for detecting lymphoblasts in cerebrospinal fluid (CSF) of patients with acute lymphoblastic leukemia (ALL) and for guiding treatment decisions. We evaluated flow cytometry immunophenotyping (FCI) performance for improving detection of central nervous system (CNS) involvement in ALL.

METHODS

This prospective study included analysis of consecutive CSF samples of patients of all ages with ALL at 3 clinical stages: new diagnosis, relapse suspicion, and after relapse treatment. Manual, cytospin, automated, and FCI methods were compared and their performance statistically assessed. Using FCI as the reference method, optimal CSF cutoff cell count that better correlated with presence of lymphoblasts was established by receiver operating characteristic (ROC) curve analysis.

RESULTS

Seventy-seven CSF samples were investigated, 35 (45.4%) from newly diagnosed cases, 30 (39%) suspicion of relapse, and 12 (15.6%) after treatment for relapse. Median manual WBC count in patients with CNS involvement detected by FCI was 3.75 cells/μL (0.0-1280), and this was also the count that best correlated with CNS infiltration (sensitivity, 50.0%; specificity, 82.2%). Compared with FCI, CCC sensitivity and specificity were 28.6% and 100%. Automated CSF WBC count in patients with CNS involvement detected by FCI was 5 (0.0-1578). For automated count, optimal WBC cutoff was 4.5 cells/μL (sensitivity, 62.5%; specificity, 70.5%).

CONCLUSION

Flow cytometry immunophenotyping complements conventional cytospin analysis for detection of lymphoblasts in the CSF of ALL patients at any clinical stage.

Oncogenetic mutations combined with MRD improve outcome prediction in pediatric T-cell acute lymphoblastic leukemia

Risk stratification in childhood T-cell acute lymphoblastic leukemia (T-ALL) is mainly based on minimal residual disease (MRD) quantification. Whether oncogenetic mutation profiles can improve the discrimination of MRD-defined risk categories was unknown. Two hundred and twenty FRALLE2000T-treated patients were tested retrospectively for NOTCH1/FBXW7/RAS and PTEN alterations. Patients with NOTCH1/FBXW7 (N/F) mutations and RAS/PTEN (R/P) germ line (GL) were classified as oncogenetic low risk (gLoR; n = 111), whereas those with N/F GL and R/P GL mutations or N/F and R/P mutations were classified as high risk (gHiR; n = 109). Day 35 MRD status was available for 191 patients. Five-year cumulative incidence of relapse (CIR) and disease-free survival were 36% and 60% for gHiR patients and 11% and 89% for gLoR patients, respectively. Importantly, among the 60% of patients with MRD <10^-4, 5-year CIR was 29% for gHiR patients and 4% for gLoR patients. Based on multivariable Cox models and stepwise selection, the 3 most discriminating variables were the oncogenetic classifier, MRD, and white blood cell (WBC) count. Patients harboring a WBC count ≥200 × 10⁹/L, gHiR classifier, and MRD ≥10^-4 demonstrated a 5-year CIR of 46%, whereas the 58 patients (30%) with a WBC count <200 × 10⁹/L, gLoR classifier, and MRD <10^-4 had a very low risk of relapse, with a 5-year CIR of only 2%. In childhood T-ALL, the N/F/R/P mutation profile is an independent predictor of relapse. When combined with MRD and a WBC count ≥200 × 10⁹/L, it identifies a significant subgroup of patients with a low risk of relapse.

Initial Diagnostic Workup of Acute Leukemia: Guideline From the College of American Pathologists and the American Society of Hematology

CONTEXT

- A complete diagnosis of acute leukemia requires knowledge of clinical information combined with morphologic evaluation, immunophenotyping and karyotype analysis, and often, molecular genetic testing. Although many aspects of the workup for acute leukemia are well accepted, few guidelines have addressed the different aspects of the diagnostic evaluation of samples from patients suspected to have acute leukemia.

OBJECTIVE

- To develop a guideline for treating physicians and pathologists involved in the diagnostic and prognostic evaluation of new acute leukemia samples, including acute lymphoblastic leukemia, acute myeloid leukemia, and acute leukemias of ambiguous lineage.

DESIGN

- The College of American Pathologists and the American Society of Hematology convened a panel of experts in hematology and hematopathology to develop recommendations. A systematic evidence review was conducted to address 6 key questions. Recommendations were derived from strength of evidence, feedback received during the public comment period, and expert panel consensus.

RESULTS

- Twenty-seven guideline statements were established, which ranged from recommendations on what clinical and laboratory information should be available as part of the diagnostic and prognostic evaluation of acute leukemia samples to what types of testing should be performed routinely, with recommendations on where such testing should be performed and how the results should be reported.

CONCLUSIONS

- The guideline provides a framework for the multiple steps, including laboratory testing, in the evaluation of acute leukemia samples. Some aspects of the guideline, especially molecular genetic testing in acute leukemia, are rapidly changing with new supportive literature, which will require on-going updates for the guideline to remain relevant.

New oncogenic subtypes in pediatric B-cell precursor acute lymphoblastic leukemia

Until recently, 20% to 30% of pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL) could not be classified into any of the established molecular subtypes. Recent molecular studies of such cases have, however, further clarified their mutational spectrum and identified new oncogenic subtypes consisting of cases with DUX4 rearrangements, ETV6-RUNX1-like gene expression, MEF2D rearrangements, and ZNF384 rearrangements. In this review, we describe these new subtypes, which account for up to 50% of previously unclassified pediatric BCP-ALL cases.

Cytogenetic Profile and FLT3 Gene Mutations of Childhood Acute Lymphoblastic Leukemia

Background:

Childhood acute lymphoblastic leukemia (ALL) is characterized by recurrent genetic aberrations. The identification of those abnormalities is clinically important because they are considered significant risk-stratifying markers.

Aims:

There are insufficient data of cytogenetic profiles in Saudi Arabian patients with childhood ALL leukemia. We have examined a cohort of 110 cases of ALL to determine the cytogenetic profiles and prevalence of FLT3 mutations and analysis of the more frequently observed abnormalities and its correlations to other biologic factors and patient outcomes and to compare our results with previously published results.

Materials and methods:

Patients—We reviewed all cases from 2007 to 2016 with an established diagnosis of childhood ALL. Of the 110 patients, 98 were B-lineage ALL and 12 T-cell ALL. All the patients were treated by UKALL 2003 protocol and risk stratified according previously published criteria. Cytogenetic analysis—Chromosome banding analysis and fluorescence in situ hybridization were used to detect genetic aberrations. Analysis of FLT3 mutations—Bone marrow or blood samples were screened for FLT3 mutations (internal tandem duplications, and point mutations, D835) using polymerase chain reaction methods.

Result:

Cytogenetic analysis showed chromosomal anomalies in 68 out of 102 cases with an overall incidence 66.7%. The most frequent chromosomal anomalies in ALL were hyperdiploidy, t(9;22), t(12;21), and MLL gene rearrangements. Our data are in accordance with those published previously and showed that FLT3 mutations are not common in patients with ALL (4.7%) and have no prognostic relevance in pediatric patients with ALL. On the contrary, t(9;22), MLL gene rearrangements and hypodiploidy were signs of a bad prognosis in childhood ALL with high rate of relapse and shorter overall survival compared with the standard-risk group (P = .031).The event-free survival was also found to be worse (P = .040).

Conclusions:

Our data are in accordance with those published previously, confirming the overall frequency of cytogenetic abnormalities and their prognostic relevance.

Risk of hospitalization among survivors of childhood and adolescent acute lymphoblastic leukemia compared to siblings and a general population sample

BACKGROUND

Acute Lymphoblastic Leukemia (ALL) has a high survival rate, but cancer-related late effects in the early post-treatment years need documentation. Hospitalizations are an indicator of the burden of late effects. We identify rates and risk factors for hospitalization from five to ten years after diagnosis for childhood and adolescent ALL survivors compared to siblings and a matched population sample.

METHODS

176 ALL survivors were diagnosed at ≤22 years between 1998 and 2008 and treated at an Intermountain Healthcare facility. The Utah Population Database identified siblings, an age- and sex-matched sample of the Utah population, and statewide inpatient hospital discharges. Sex- and birth year-adjusted Poisson models with Generalized Estimating Equations and robust standard errors calculated rates and rate ratios. Cox proportional hazards models identified demographic and clinical risk factors for hospitalizations among survivors.

RESULTS

Hospitalization rates for survivors (Rate:3.76, 95% CI=2.22-6.36) were higher than siblings (Rate:2.69, 95% CI=1.01-7.18) and the population sample (Rate:1.87, 95% CI=1.13-3.09). Compared to siblings and population comparisons, rate ratios (RR) were significantly higher for survivors diagnosed between age 6 and 22 years (RR:2.87, 95% CI=1.03-7.97 vs siblings; RR:2.66, 95% CI=1.17-6.04 vs population comparisons). Rate ratios for diagnosis between 2004 and 2008 were significantly higher compared to the population sample (RR:4.29, 95% CI=1.49, 12.32), but not siblings (RR:2.73, 95% CI=0.54, 13.68). Survivors originally diagnosed with high-risk ALL did not have a significantly higher risk than siblings or population comparators. However, high-risk ALL survivors (Hazard ratio [HR]:3.36, 95% CI=1.33-8.45) and survivors diagnosed from 2004 to 2008 (HR:9.48, 95% CI=1.93-46.59) had the highest risk compared to their survivor counterparts.

CONCLUSIONS

Five to ten years after diagnosis is a sensitive time period for hospitalizations in the ALL population. Survivors of childhood ALL require better long-term surveillance.

Copy Number Alterations Associated with Acute Lymphoblastic Leukemia in Mexican Children. A report from The Mexican Inter-Institutional Group for the identification of the causes of childhood leukemia

B-cell precursor acute lymphocytic leukemia (B-ALL) represents a worldwide public health issue. Particularly, Mexico is one of the countries with the highest incidence of ALL in children. Between the multiple factors involved in ALL etiology, genetic alterations are clearly one of the most relevant features. In this work, a group of 24 B-ALL patients, all negative for the four most frequent gene fusions (ETV6-RUNX1, BCR-ABL1, TCF3-PBX1 and MLL-AF4), were included in a high-resolution microarray analysis in order to evaluate genomic copy-number alterations (CNAs). The results of this preliminary report showed a broad genomic heterogeneity among the studied samples; 58% of the patients were hyperdiploid and 33% displayed a chromosome 9p deletion of variable length affecting genes CDKN2A/B, two patients displayed genomic instability with a high number of focal CNAs, three patients presented unique duplications affecting 2q, 12p and 1q, respectively, and one patient displayed no copy number imbalances. The copy-number profile of 44 genes previously related to B-ALL was heterogeneous as well. Overall results highlight the need for a detailed description of the genetic alterations in ALL cancer cells in order to understand the molecular pathogenesis of the disease and to identify any prognostic markers with clinical significance.

Analysis of Thiopurine S-Methyltransferase Deficient Alleles in Acute Lymphoblastic Leukemia Patients in Mexican Patients

BACKGROUND AND AIMS

It has been demonstrated that heterozygote and homozygote thiopurine S-methyltransferase (TPMT) mutant allele carriers are at high risk to develop severe and potentially fatal hematopoietic toxicity after treatment with standard doses of 6-mercaptopurine (6-MP) and methotrexate (MX). Those drugs are the backbone of acute lymphoblastic leukemia (ALL) and several autoimmune disease treatments. We undertook this study to determine the frequency of the TPMT deficient alleles in children with ALL and non-ALL subjects from Mexico City and Yucatan, Mexico.

METHODS

We included 849 unrelated subjects, of which 368 ALL children and 342 non-ALL subjects were from Mexico City, and 60 ALL cases and 79 non-ALL individuals were from Yucatan. Genotyping of the rs1800462, rs1800460 and rs1142345 SNPs was performed by 5'exonuclease technique using TaqMan probes (Life Technologies Foster City, CA).

RESULTS

The mutant TPMT alleles were present in 4.8% (81/1698 chromosomes) and only 0.2% were homozygote TPMT*3A/TPMT*3A. We did not find statistically significant differences in the distribution of the mutant alleles between patients from Mexico City and Yucatan in either ALL cases or non-ALL. Nonetheless, the TPMT*3C frequency in ALL patients was higher than non-ALL subjects (p = 0.03). To note, the null homozygous TPMT*3A/TPMT*3A genotype was found in 2.5% of the non-ALL subjects.

CONCLUSIONS

TPMT mutant alleles did not exhibit differential distribution between both evaluated populations; however, TPMT*3C is overrepresented in ALL cases in comparison with non-ALL group. Assessing the TPMT mutant alleles could benefit the ALL children and those undergoing 6-MP and MX treatment.

Novel therapy for childhood acute lymphoblastic leukemia

INTRODUCTION

During recent decades, the prognosis of childhood acute lymphoblastic leukemia (ALL) has improved dramatically, nowadays, reaching a cure rate of almost 90%. These results are due to a better management and combination of old therapies, refined risk-group stratification and emergence of minimal residual disease (MRD) combined with treatment's intensification for high-risk subgroups. However, the subgroup of patients with refractory/relapsed ALL still presents a dismal prognosis indicating necessity for innovative therapeutic approaches. Areas covered: We performed an exhaustive review of current first-line therapies for childhood ALL in the worldwide main consortia, summarized the major advances for front-line and relapse treatment and highlighted recent and promising innovative therapies with an overview of the most promising ongoing clinical trials. Expert opinion: Two major avenues marked the beginning of 21^st century. First, is the introduction of tyrosine-kinase inhibitor coupled to chemotherapy for treatment of Philadelphia positive ALL opening new treatment possibilities for the recently identified subgroup of Ph-like ALL. Second, is the breakthrough of immunotherapy, notably CAR T-cell and specific antibody-based therapy, with remarkable success observed in initial studies. This review gives an insight on current knowledge in these innovative therapeutic directions, summarizes currently ongoing clinical trials and addresses challenges these approaches are faced with.

Prognostic factors and treatment of pediatric acute lymphoblastic leukemia

The event-free survival (EFS) for pediatric acute lymphoblastic leukemia (ALL) has shown remarkable improvement in the past several decades. In Korea also, a recent study showed 10-year EFS of 78.5%. Much of the improved outcome for pediatric ALL stems from the accurate identification of prognostic factors, the designation of risk group based on these factors, and treatment of appropriate duration and intensity according to risk group, done within the setting of cooperative clinical trials. The schema of first-line therapy for ALL remains mostly unchanged, although many groups have now reported on the elimination of cranial irradiation in all patients with low rates of central nervous system relapse. Specific high risk subgroups, such as Philadelphia chromosome-positive (Ph+) ALL and infant ALL continue to have significantly lower survival than other ALL patients. The introduction of tyrosine kinase inhibitors into therapy has led to enhanced outcome for Ph+ ALL patients. Infant ALL patients, particularly those with MLL rearrangements, continue to have poor outcome, despite treatment intensification including allogeneic hematopoietic cell transplantation. Relapsed ALL is a leading cause of mortality in pediatric cancer. Recent advances in immunotherapy targeting the CD19 of the ALL blast have shown remarkable efficacy in some of these relapsed and refractory patients. With improved survival, much of the current focus is on decreasing the long-term toxicities of treatment.

Increased Risk of Thai Childhood Acute Lymphoblastic Leukemia with the MiR196a2 T>C Polymorphism

Objectives:

This study assessed associations of the miR196a2 (rs11614913) T>C polymorphism withsusceptibility to childhood acute lymphoblastic leukemia (ALL) and clinical outcomes.

Materials and Methods:

Blood DNA samples from 104 childhood ALL patients and 180 healthy children were studied for the miR-196a2 (rs11614913) polymorphism using a polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) approach.

Results:

The frequency of the miR-196a2 (rs11614913) T allele in controls was 0.51 compared with 0.33 in ALL cases. In this study, CC, TC heterozygote and CC/TC genotypes were significantly associated with increase childhood ALL susceptibility compared with the TT wild type (OR =4.321, 95% CI = 2.091-8.930 p=0.000, OR = 2.248, 95% CI =1.103-4.579, p=0.024, OR = 2.921, 95% CI = 1.504-5.673 p=0.001, respectively). However, the miR-196a2 (rs11614913) T>C polymorphism was not associated with demographic data or clinico-pathological data in ALL cases.

Conclusion:

CC, TC and CC+TC genotypes of miR-196a2 (rs11614913) was significantly associated with increased susceptibility in Thai childhood ALL but not with clinical variables.

The Behavior Rating Inventory of Executive Function (BRIEF) to Identify Pediatric Acute Lymphoblastic Leukemia (ALL) Survivors At Risk for Neurocognitive Impairment

Neurocognitive problems, including executive dysfunction, are potential late effects of pediatric acute lymphoblastic leukemia treatment. Surveillance for neurocognitive impairment in a timely and efficient manner is imperative to ongoing clinical care. We sought to determine if the Behavior Rating Inventory of Executive Function (BRIEF) Parent Form identified leukemia survivors with cognitive impairment. In this 28-site cross-sectional study, parents of 256 children, a mean of 8.9±2.2 years after treatment for standard-risk precursor-B acute lymphoblastic leukemia and in first remission, completed the BRIEF. We used a multivariate logistic regression to calculate the association between elevated scores on 3 composite BRIEF indices (Behavioral Regulation Index, Metacognition Index, Global Executive Composite [GEC]) and special education and attention-deficit/hyperactivity disorder (ADHD) outcomes. All BRIEF index scores were significantly associated with receipt of special education services or ADHD. The BRI was most strongly associated with ADHD (odds ratios=4.33; 95% confidence interval, 1.72-10.9). The GEC was most strongly associated with ADHD (odds ratios=4.46; 95% confidence interval, 1.77-11.22). Elevated scores on the BRIEF GEC were associated with low sensitivity (24.1 to 39.1) for detecting the outcomes but better specificity (range, 87.7 to 89.3). These results suggest that the parent-completed BRIEF is associated with clinical outcomes but is not a sensitive tool to identify leukemia survivors that require a comprehensive neuropsychological assessment.

Mercaptopurine Ingestion Habits, Red Cell Thioguanine Nucleotide Levels, and Relapse Risk in Children With Acute Lymphoblastic Leukemia: A Report From the Children's Oncology Group Study AALL03N1

Purpose Children with acute lymphoblastic leukemia (ALL) are generally instructed to take mercaptopurine (6-MP) in the evening and without food or dairy products. This study examines the association between 6-MP ingestion habits and 6-MP adherence, red cell thioguanine nucleotide (TGN) levels, and risk of relapse in children with TMPT wild-type genotype. Methods Participants included 441 children with ALL receiving oral 6-MP for maintenance. Adherence was monitored over 48,086 patient-days using the Medication Event Monitoring System; nonadherence was defined as adherence rate < 95%. 6-MP ingestion habits examined included: takes 6-MP with versus never with food, takes 6-MP with versus never with dairy, and takes 6-MP in the evening versus morning versus varying times. Results Median age at study was 6 years (range, 2 to 20 years); 43.8% were nonadherent. Certain 6-MP ingestion habits were associated with nonadherence (taking 6-MP with dairy [odds ratio (OR), 1.9; 95% CI, 1.3 to 2.9; P = .003] and at varying times [OR, 3.4; 95% CI, 1.8 to 6.3; P = .0001]). After adjusting for adherence and other prognosticators, there was no association between 6-MP ingestion habits and relapse risk (6-MP with food: hazard ratio [HR], 0.7; 95% CI, 0.3 to 1.9; P = .5; with dairy: HR, 0.3; 95% CI, 0.07 to 1.5; P = .2; taken in evening/night: HR, 1.1; 95% CI, 0.2 to 7.8; P = .9; at varying times: HR, 0.3; 95% CI, 0.04 to 2.7; P = .3). Among adherent patients, there was no association between red cell TGN levels and taking 6-MP with food versus without (206.1 ± 107.1 v 220.6 ± 121.6; P = .5), with dairy versus without (220.1 ± 87.8 v 216.3 ± 121.3; P =.7), or in the evening/night versus morning/midday versus varying times (218.8 ± 119.7 v 195.5 ± 82.3 v 174.8 ± 93.4; P = .6). Conclusion Commonly practiced restrictions surrounding 6-MP ingestion might not influence outcome but may hinder adherence. Future recommendations regarding 6-MP intake during maintenance therapy for childhood ALL should aim to simplify administration.

Influence of Musculoskeletal Manifestations as the Only Presenting Symptom in B-Cell Acute Lymphoblastic Leukemia

OBJECTIVE

To evaluate the clinical and prognostic impact of musculoskeletal manifestations as the only initial presenting symptom in childhood acute lymphoblastic leukemia (ALL).

STUDY DESIGN

We retrospectively reviewed 158 children with precursor B-cell type ALL who were followed up for >2 years. The patients were assigned to the groups musculoskeletal manifestations (n = 24) or nonmusculoskeletal manifestations (n = 134) based on initial presenting symptom. The symptom duration (regarding any initial presenting symptom) and the leukemic symptom duration (regarding symptoms of systemic manifestation, such as fever, bleeding, or pallor) were assessed, along with other clinical characteristics.

RESULTS

The musculoskeletal manifestations group exhibited a longer symptom duration than the nonmusculoskeletal manifestations group (43 days vs 22 days, P = .006), but overall survival did not significantly differ between the groups. Multivariate analysis indicated that a longer symptom duration did not affect prognosis but that a longer leukemic symptom duration was associated with a poorer prognosis (hazard ratio, 7.720; P = .048).

CONCLUSION

Musculoskeletal manifestations are associated significantly with diagnostic delay, but this delay does not affect the prognosis. Diagnostic delay after the onset of leukemic symptoms, however, does appear to affect the prognosis. Intensive evaluations for hematologic malignancies may be unnecessary in children who complain of limb pain without any definite cause, unless they also present with accompanying leukemic symptoms.

Comparison of self-report and electronic monitoring of 6MP intake in childhood ALL: a Children's Oncology Group study

Adequate exposure to oral 6-mercaptopurine (6MP) during maintenance therapy for childhood acute lymphoblastic leukemia (ALL) is critical for sustaining durable remissions; accuracy of self-reported 6MP intake is unknown. We aimed to directly compare self-report to electronic monitoring (Medication Event Monitoring System [MEMS]) and identify predictors of overreporting in a cohort of 416 children with ALL in first remission over 4 study months (1344 patient-months for the cohort) during maintenance therapy. Patients were classified as "perfect reporters" (self-report agreed with MEMS), "overreporters" (self-report was higher than MEMS by ≥5 days/month for ≥50% of study months), and "others" (not meeting criteria for perfect reporter or overreporter). Multivariable logistic regression examined sociodemographic and clinical characteristics, 6MP dose intensity, TPMT genotype, thioguanine nucleotide levels, and 6MP nonadherence (MEMS-based adherence <95%) associated with the overreporter phenotype; generalized estimating equations compared 6MP intake by self-report and MEMS. Self-reported 6MP intake exceeded MEMS at least some of the time in 84% of patients. Fifty patients (12%) were classified as perfect reporters, 98 (23.6%) as overreporters, 2 (0.5%) as underreporters, and 266 (63.9%) as others. In multivariable analysis, the following variables were associated with the overreporter phenotype: non-white race: Hispanic, odds ratio (OR), 2.4, P = .02; Asian, OR, 3.1, P = .02; African American, P < .001; paternal education less than college (OR, 1.4, P = .05); and 6MP nonadherence (OR, 9.4, P < .001). Self-report of 6MP intake in childhood ALL overestimates true intake, particularly in nonadherent patients, and should be used with caution.

Inferior outcomes for black children with high risk acute lymphoblastic leukemia and the impact of socioeconomic variables

BACKGROUND

While significant improvements have been made for children with acute lymphoblastic leukemia (ALL) in the United States over the past 20 years, black patients continue to have inferior outcomes. The full impact of socioeconomic variables on outcomes in this minority population is not entirely understood.

PROCEDURE

Disease characteristics, demographic, and socioeconomic status (SES) variables were collected on black (n = 44) and white (n = 178) patients diagnosed at the University of Alabama at Birmingham. Cox proportional hazard regression was used to evaluate the influence of SES and insurance status on survival.

RESULTS

As a cohort, 5-year overall survival (OS) was 87% (82-91%), with a median follow-up of 99 months. In univariable analysis, black race was not significantly associated with a higher risk of death or relapse and death. White and black patients with standard-risk leukemia had excellent outcomes, with 97% (91-99%) and 96% (75-99%) 5-year OS, respectively. In contrast, for high-risk disease, white patients had a statistically significant improved 5-year OS rates compared with black patients (79% [68-87%] vs. 52% [28-72%]). Black children were more likely to have public insurance, and, in multivariable analysis, this was associated with a trend toward an improved outcome. Black patients also had poorer census tract-level SES parameters, but these variables were not associated with survival.

CONCLUSION

Our study demonstrates significantly inferior outcomes for black children with high-risk leukemia. These outcome disparities were not related to SES variables, including poverty or private insurance coverage, suggesting the involvement of other factors and highlighting the need for a prospective investigative analysis.

Genomic characterization of paediatric acute lymphoblastic leukaemia: an opportunity for precision medicine therapeutics

Major advances in genetic and epigenetic profiling of acute lymphoblastic leukaemia (ALL) have enhanced the understanding of key biological subsets of de novo and relapsed ALL, which has led to improved risk stratification of patients. These achievements have further defined critical leukaemia-associated pathways and somatic alterations that may be preferentially sensitive to treatment with kinase inhibitors, epigenetic therapy or other novel agents. Therapeutic success in childhood ALL currently relies upon refined risk stratification of patients based on (i) underlying biological and clinical characteristics, and (ii) depth of initial treatment response with appropriate modulation of chemotherapy intensity. This review describes the current mutational landscape of childhood ALL and discusses opportunities for substantial improvements in survival with implementation of molecularly targeted therapies.

Tumor suppressors BTG1 and IKZF1 cooperate during mouse leukemia development and increase relapse risk in B-cell precursor acute lymphoblastic leukemia patients

Deletions and mutations affecting lymphoid transcription factor IKZF1 (IKAROS) are associated with an increased relapse risk and poor outcome in B-cell precursor acute lymphoblastic leukemia. However, additional genetic events may either enhance or negate the effects of IKZF1 deletions on prognosis. In a large discovery cohort of 533 childhood B-cell precursor acute lymphoblastic leukemia patients, we observed that single-copy losses of BTG1 were significantly enriched in IKZF1-deleted B-cell precursor acute lymphoblastic leukemia (P=0.007). While BTG1 deletions alone had no impact on prognosis, the combined presence of BTG1 and IKZF1 deletions was associated with a significantly lower 5-year event-free survival (P=0.0003) and a higher 5-year cumulative incidence of relapse (P=0.005), when compared with IKZF1-deleted cases without BTG1 aberrations. In contrast, other copy number losses commonly observed in B-cell precursor acute lymphoblastic leukemia, such as CDKN2A/B, PAX5, EBF1 or RB1, did not affect the outcome of IKZF1-deleted acute lymphoblastic leukemia patients. To establish whether the combined loss of IKZF1 and BTG1 function cooperate in leukemogenesis, Btg1-deficient mice were crossed onto an Ikzf1 heterozygous background. We observed that loss of Btg1 increased the tumor incidence of Ikzf1^+/− mice in a dose-dependent manner. Moreover, murine B cells deficient for Btg1 and Ikzf1^+/− displayed increased resistance to glucocorticoids, but not to other chemotherapeutic drugs. Together, our results identify BTG1 as a tumor suppressor in leukemia that, when deleted, strongly enhances the risk of relapse in IKZF1-deleted B-cell precursor acute lymphoblastic leukemia, and augments the glucocorticoid resistance phenotype mediated by the loss of IKZF1 function.

Leukemic blasts are present at low levels in spinal fluid in one-third of childhood acute lymphoblastic leukemia cases

BACKGROUND

Central nervous system (CNS) involvement is associated with relapse in childhood acute lymphoblastic leukemia (ALL) and is a diagnostic challenge.

PROCEDURE

In a Nordic/Baltic prospective study, we assessed centralized flow cytometry (FCM) of locally fixed cerebrospinal fluid (CSF) samples versus local conventional cytospin-based cytology (CC) for detecting leukemic cells and evaluating kinetics of elimination of leukemic cells in CSF.

RESULTS

Among 300 patients with newly diagnosed ALL, 87 (29%) had CSF involvement by FCM, while CC was positive in 30 (10%) of 299 patients with available CC data (P < 0.001). Patients with FCM+/CC+ had higher CSF leukemic blast counts compared to patients positive by FCM only (medians: 0.10 vs. 0.017 leukemic blasts/μl, P = 0.006). Patients positive by FCM had higher white blood cell counts in peripheral blood than patients negative by FCM (medians: 45 × 10(9) /l vs. 10 × 10(9) /l, P < 0.001), were younger (medians: 3 years vs. 4 years, P = 0.03), and more frequently had T-cell ALL (18/87 vs. 16/213, P = 0.001). At treatment day 15, five of 52 patients (10%) who had CSF positive by FCM at diagnosis remained so despite at least two doses of weekly intrathecal chemotherapy.

CONCLUSIONS

Longer follow-up is needed to clarify whether FCM positivity has prognostic significance and is an indicator for intensified CNS-directed therapy.

Treatment of children with acute lymphoblastic leukemia with risk group based intensification and omission of cranial irradiation: A Korean study of 295 patients

BACKGROUND

Recent studies indicate 70-80% event-free survival (EFS) for pediatric acute lymphoblastic leukemia (ALL). In this study, we report the outcome of 295 children and adolescents treated at our institution, with stratification into four risk groups, and omission of cranial irradiation in all patients.

PROCEDURE

Patients were diagnosed from January 2005 to December 2011 and classified and treated as low, standard, high, and very high risk groups. A delayed intensification phase was given twice for high and very high risk groups. None of the patients received cranial irradiation for central nervous system (CNS) prophylaxis.

RESULTS

The 10-year EFS and overall survival (OS) were 78.5 ± 2.5% and 81.9 ± 2.7%, respectively. EFS according to risk group was as follows: low risk 91.2 ± 3.7%, standard risk 98.1 ± 1.9%, high risk 81.5 ± 4.3%, very high risk 59.4 ± 5.3%. In a multivariate analysis, high hyperdiploidy and infant ALL were significant predictors of EFS. Cumulative incidence of any relapse, isolated CNS relapse, and any CNS relapse were 17.1 ± 2.3%, 1.5 ± 0.7%, and 2.3 ± 0.9%, respectively. Other events included infection-related deaths during remission induction chemotherapy (3), primary refractory disease (2), and treatment-related deaths in first complete remission (8).

CONCLUSIONS

In this single-institution study of Korean pediatric ALL patients, risk group based intensification with omission of cranial irradiation resulted in EFS comparable to previous studies, excellent survival of low- and standard-risk patients, and a low rate of CNS relapse.

The Impact of Socioeconomic Factors on the Outcome of Childhood Acute Lymphoblastic Leukemia (ALL) Treatment in a Low/Middle Income Country (LMIC)

Survival for childhood acute lymphoblastic leukemia (ALL) has improved significantly, but these benefits may not be available to many children from low and middle income countries, where reasons for treatment failure may be unique to their environment. We retrospectively reviewed data on pediatric (1 to 18 y or younger) patients with newly diagnosed ALL treated over 5 years at a children's cancer hospital in Pakistan. Patients were treated with modified Berlin-Frankfurt-Muenster -based therapy without risk stratification. There were 255 children with a median age of 7 years (mean, 7.65 y) and a male preponderance (M:F=1.6:1). 20% had T-ALL, one-third had white blood cells >50×10/L and 13.7% central nervous system disease. A majority (56.5%) was malnourished. In total, 49 (19.2%) died before the end of induction and 21 died in complete remission. Most deaths were infection-related. A total of 50 patients relapsed and 19 abandoned therapy after complete remission. Five-year overall survival is 52.9% with abandonment censored and 45.8% with abandonment as an event. Overall survival was related to socioeconomic status but not to known risk factors. The outcome of ALL at our center is suboptimal and associated with factors not commonly seen in developed countries. Special attention to early diagnosis, infection control, and parental educational are needed to improve the survival.

Treatment of Common Childhood Malignancies

Malignancy is the fourth leading cause of death in persons aged 1 to 19 years. The success of the pediatric oncology cooperative group clinical trials has allowed a systematic approach to the treatment of relatively rare malignancies. Each trial builds on previous results in terms of both survival and toxicity. This article will discuss the current treatment regimens for several of the more common pediatric malignancies and their long-term complications developed through this process.

Prognostic impact of RUNX1 and ETV6 gene copy number on pediatric B-cell precursor acute lymphoblastic leukemia with or without hyperdiploidy

The ETV6/RUNX1 fusion gene is a valuable prognostic marker that is frequently observed in B-cell precursor acute lymphoblastic leukemia (B-cell ALL). However, the clinical significance of copy number aberrations in these genes remains unclear. In this study, the effects of various aberrations inETV6 and RUNX1 gene copy number on disease prognosis were evaluated in 21 pediatric patients diagnosed with B-cell ALL with/without t(12;21). The prognostic significance of changes in gene copy number of ETV6 or RUNX1 in the presence or absence of hyperdiploidy, trisomy 21, and t(12;21) translocation were also evaluated. RUNX1 gene copy number amplifications were detected in 83 % of the patients who lacked t(12;21) and in all of the patients with hyperdiploidy. Trisomy 21 was detected in 78 % of the patients with hyperdiploidy. Changes in ETV6 gene copy number were detected in patients who lacked both the t(12;21) translocation and RUNX1 gene copy number amplifications. However, RUNX1 gene copy number amplification and ETV6 deletion were observed in all of the patients with t(12;21). RUNX1 gene copy number amplification was associated with hyperdiploidy, but not with t(12;21). Thus, the evaluation of distinct FISH and cytogenetic patterns in patients with B-cell ALL may strengthen the prognostic significance of changes in gene copy number.

Gene Signature of High White Blood Cell Count in B-Precursor Acute Lymphoblastic Leukemia

In this study we sought to identify genetic factors associated with the presenting white blood cell (WBC) count in B-precursor acute lymphoblastic leukemia (BP-ALL). Using ETV6-RUNX1-positive BP-ALL patient samples, a homogeneous subtype, we identified 16 differentially expressed genes based on the presenting WBC count (< 50,000/cumm vs > 50,000). We further confirmed that IL1R1, BCAR3, KCNH2, PIR, and ZDHHC23 were differentially expressed in a larger cohort of ETV6-RUNX1-negative BP-ALL patient samples. Statistical analysis demonstrated that expression levels of these genes could accurately categorize high and low WBC count subjects using two independent patient sets, representing positive and negative ETV6-RUNX1 cases. Further studies in leukemia cell line models will better delineate the role of these genes in regulating the white blood cell count and potentially identify new therapeutic targets.

Outcome and Prognostic Factors for ETV6/RUNX1 Positive Pediatric Acute Lymphoblastic Leukemia Treated at a Single Institution in Korea

Purpose

ETV6/RUNX1 (+) acute lymphoblastic leukemia (ALL), which is the most common genetic subtype of pediatric ALL, has a favorable prognosis. In this study, we analyzed the outcome of ETV6/RUNX1 (+) ALL patients treated at our institution with the aim of identifying significant prognostic variables.

Materials and Methods

Sixty-three patients were diagnosed with ETV6/RUNX1 (+) ALL from 2005 to 2011. Prognostic variables studied included minimal residual disease (MRD) as detected by ETV6/RUNX1 (+) fusion, and the presence of additional cytogenetic abnormalities.

Results

The 5-year event-free survival was 84.1±4.6%, with 10 patients relapsing at a median of 28.3 months from diagnosis for a 5-year cumulative incidence of relapse of 15.9±4.6%. Multivariate analysis revealed that the presence MRD, as detected by real-time quantitative-polymerase chain reaction or fluorescence in situ hybridization for ETV6/RUNX1 fusion at end of remission induction, and the presence of additional structural abnormalities of 12p (translocations or inversions) negatively affected outcome. Despite treatment such as allogeneic hematopoietic cell transplantation, eight of the 10 relapsed patients died from disease progression for overall survival of 82.5±6.9%.

Conclusion

ETV6/RUNX1 (+) ALL may be heterogeneous in terms of prognosis, and variables such as MRD at end ofremission induction or additional structural abnormalities of 12p could define a subset of patients who are likely to have poor outcome.

Oxidative Stress, Motor Abilities, and Behavioral Adjustment in Children Treated for Acute Lymphoblastic Leukemia

PURPOSE/OBJECTIVES

To examine associations among oxidative stress, fine and visual-motor abilities, and behavioral adjustment in children receiving chemotherapy for acute lymphoblastic leukemia (ALL)
.

DESIGN

A prospective, repeated-measures design
.

SETTING

Two pediatric oncology settings in the southwestern United States.

SAMPLE

89 children with ALL were followed from diagnosis to the end of chemotherapy.

METHODS

Serial cerebrospinal fluid samples were collected during scheduled lumbar punctures and analyzed for oxidative stress biomarkers. Children completed fine motor dexterity, visual processing speed, and visual-motor integration measures at three time points. Parents completed child behavior ratings at the same times.

MAIN RESEARCH VARIABLES

Oxidative stress, fine motor dexterity, visual processing, visual-motor integration, and behavioral adjustment
.

FINDINGS

Children with ALL had below-average fine motor dexterity, visual processing speed, and visual-motor integration following the induction phase of ALL therapy. By end of therapy, visual processing speed normalized, and fine motor dexterity and visual-motor integration remained below average. Oxidative stress measures correlated with fine motor dexterity and visual-motor integration. Decreased motor functioning was associated with increased hyperactivity and anxiety
.

CONCLUSIONS

Oxidative stress occurs following chemo-therapy for childhood ALL and is related to impaired fine motor skills and visual symptoms
.

IMPLICATIONS FOR NURSING

Early intervention should be considered to prevent fine motor and visual-spatial deficits, as well as behavioral problems.

Dexamethasone and High-Dose Methotrexate Improve Outcome for Children and Young Adults With High-Risk B-Acute Lymphoblastic Leukemia: A Report From Children's Oncology Group Study AALL0232

PURPOSE

Survival for children and young adults with high-risk B-acute lymphoblastic leukemia has improved significantly, but 20% to 25% of patients are not cured. Children's Oncology Group study AALL0232 tested two interventions to improve survival.

PATIENTS AND METHODS

Between January 2004 and January 2011, AALL0232 enrolled 3,154 participants 1 to 30 years old with newly diagnosed high-risk B-acute lymphoblastic leukemia. By using a 2 × 2 factorial design, 2,914 participants were randomly assigned to receive dexamethasone (14 days) versus prednisone (28 days) during induction and high-dose methotrexate versus Capizzi escalating-dose methotrexate plus pegaspargase during interim maintenance 1.

RESULTS

Planned interim monitoring showed the superiority of the high-dose methotrexate regimens, which exceeded the predefined boundary and led to cessation of enrollment in January 2011. At that time, participants randomly assigned to high-dose methotrexate during interim maintenance 1 versus those randomly assigned to Capizzi methotrexate had a 5-year event-free survival (EFS) of 82% versus 75.4% (P = .006). Mature final data showed 5-year EFS rates of 79.6% for high-dose methotrexate and 75.2% for Capizzi methotrexate (P = .008). High-dose methotrexate decreased both marrow and CNS recurrences. Patients 1 to 9 years old who received dexamethasone and high-dose methotrexate had a superior outcome compared with those who received the other three regimens (5-year EFS, 91.2% v 83.2%, 80.8%, and 82.1%; P = .015). Older participants derived no benefit from dexamethasone during induction and experienced excess rates of osteonecrosis.

CONCLUSION

High-dose methotrexate is superior to Capizzi methotrexate for the treatment of high-risk B-acute lymphoblastic leukemia, with no increase in acute toxicity. Dexamethasone given during induction benefited younger children but provided no benefit and was associated with a higher risk of osteonecrosis among participants 10 years and older.

Trends in management of acute lymphoblastic leukemia: Influence of insurance based healthcare and treatment compliance on the outcome of adolescents and adults with acute lymphoblastic leukemia

AIM

In this study, we attempted to analyze the impact of insurance based health care system and treatment compliance on the outcome of adolescent and adults with acute lymphoblastic leukemia (ALL).

MATERIALS AND METHODS

Patients who underwent treatment for ALL during the period 2003-2011 were enrolled into this retrospective study. Patients on supportive or palliative care only and patients with age <10 years were excluded. The hospital records and tumor registry records were studied. Patients were stratified into two groups, Group A (prior to the introduction of state health insurance [SHI], 2003-2007) and Group B (after the introduction of SHI, 2008-2011). Overall survival (OS) was calculated using Kaplan-Meier method.

RESULTS

A total of 420 patients with suspected or confirmed ALL visited our center during the study period and 179 patients (87 in Group A and 92 in Group B) were considered for inclusion. The median age in years (range) was 18 (10-57) and 18 (10-58) respectively in Groups A and B with males more than females. Median OS (95% CI) was 9 (6.7-11.2) and 12 (7.3-16.7) months in the Groups A and B respectively (P = 0.265). Poor treatment compliance in both groups was high (36% in Group A and 41% in Group B, [P = 0.107]) with lower default rates in Group B (P = 0.019). Patients with good compliance in the total study population and the individual study groups had significantly better OS.

CONCLUSIONS

Insurance based health care has improved outcomes in the present study but not compliance to treatment. Significantly better OS was observed in patients with good compliance.

The Association Between Motor Skills and Academic Achievement Among Pediatric Survivors of Acute Lymphoblastic Leukemia

OBJECTIVE

Assess the association between fine motor (FM) and visual-motor integration (VMI) skills and academic achievement in pediatric acute lymphoblastic leukemia (ALL) survivors.

METHODS

In this 28-site cross-sectional study of 256 children in first remission, a mean of 8.9 ± 2.2 years after treatment for standard-risk precursor-B ALL, validated measures of FM, VMI, reading, math, and intelligence were administered at mean follow-up age of 12.8 ± 2.5 years. 

RESULTS

 VMI was significantly associated with written math calculation ability (p < .0069) after adjusting for intelligence (p < .0001). VMI was more strongly associated with math in those with lower intelligence (p = .0141). Word decoding was also significantly associated with VMI but with no effect modification by intelligence. FM skills were not associated with either reading or math achievement.

CONCLUSION

These findings suggest that VMI is associated with aspects of math and reading achievement in leukemia survivors. These skills may be amenable to intervention.

Systemic Exposure to Thiopurines and Risk of Relapse in Children With Acute Lymphoblastic Leukemia: A Children's Oncology Group Study

IMPORTANCE

Variability in prescribed doses of 6-mercaptopurine (6MP) and lack of adherence to a 6MP treatment regimen could result in intra-individual variability in systemic exposure to 6MP (measured as erythrocyte thioguanine nucleotide [TGN] levels) in children with acute lymphoblastic leukemia (ALL). The effect on relapse risk of this variability is unknown.

OBJECTIVE

To determine the effect of high intra-individual variability of 6MP systemic exposure on relapse risk in children with ALL.

DESIGN, SETTING, AND PARTICIPANTS

We used a prospective longitudinal design (Children's Oncology Group study [COG-AALL03N1]) to monitor 6MP and disease relapse in 742 children with ALL in ambulatory care settings of 94 participating institutions from May 30, 2005, to September 9, 2011. All participants met the following eligibility criteria: (1) diagnosis of ALL at 21 years or younger; (2) first continuous remission in progress at the time of study entry; (3) receiving self-, parent-, or caregiver-administered oral 6MP during maintenance therapy; and (4) completion of at least 6 months of maintenance therapy at the time of study enrollment. The median patient age at diagnosis was 5 years; 68% were boys; and 43% had National Cancer Institute-based high-risk disease.

MAIN OUTCOMES AND MEASURES

Daily 6MP regimen adherence was measured over 68 716 person-days using an electronic system that recorded the date and time of each 6MP bottle opening; adherence rate was defined as the ratio of days that a 6MP bottle was opened to days thata 6MP bottle was prescribed. Average monthly 6MP dose intensity was measured over 120 439 person-days by dividing the number of 6MP doses actually prescribed by the number of planned protocol doses (75 mg/m2/d). Monthly erythrocyte TGN levels (pmol/8 × 108 erythrocytes) were measured over 6 consecutive months per patient (n = 3944 measurements). Using intra-individual coefficients of variation (CV%), patients were classified as having stable (CV% <85th percentile) vs varying (CV% ≥85th percentile) indices. Median follow-up time was 6.7 years from the time of diagnosis.

RESULTS

Adjusting for clinical prognosticators, we found that patients with 6MP nonadherence (mean adherence rate <95%) were at a 2.7-fold increased risk of relapse (95% CI, 1.3-5.6; P = .01) compared with patients with a mean adherence rate of 95% or greater. Among adherers, high intra-individual variability in TGN levels contributed to increased relapse risk (hazard ratio, 4.4; 95% CI, 1.2-15.7; P = .02). Furthermore, adherers with varying TGN levels had varying 6MP dose intensity (odds ratio [OR], 4.5; 95% CI, 1.5-13.4; P = .01) and 6MP drug interruptions (OR, 10.2; 95% CI, 2.2-48.3; P = .003).

CONCLUSIONS AND RELEVANCE

These findings emphasize the need to maximize 6MP regimen adherence and maintain steady thiopurine exposure to minimize relapse in children with ALL.

Molecular Analysis of Central Nervous System Disease Spectrum in Childhood Acute Lymphoblastic Leukemia

Treatment of the central nervous system (CNS) is an essential therapeutic component in childhood acute lymphoblastic leukemia (ALL). The goal of this study was to identify molecular signatures distinguishing patients with CNS disease from those without the disease in pediatric patients with ALL. We analyzed gene expression data from 207 pediatric patients with ALL. Patients without CNS were classified as CNS1, while those with mild and advanced CNS disease were classified as CNS2 and CNS3, respectively. We compared gene expression levels among the three disease classes. We identified gene signatures distinguishing the three disease classes. Pathway analysis revealed molecular networks and biological pathways dysregulated in response to CNS disease involvement. The identified pathways included the ILK, WNT, B-cell receptor, AMPK, ERK5, and JAK signaling pathways. The results demonstrate that transcription profiling could be used to stratify patients to guide therapeutic decision-making in pediatric ALL.

Association of body mass index and survival in pediatric leukemia: a meta-analysis

BACKGROUND

Obesity is a worldwide epidemic in children and adolescents. Adult cohort studies have reported an association between higher body mass index (BMI) and increased leukemia-related mortality; whether a similar effect exists in childhood leukemia remains controversial.

OBJECTIVE

We conducted a meta-analysis to determine whether a higher BMI at diagnosis of pediatric acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML) is associated with worse event-free survival (EFS), overall survival (OS), and cumulative incidence of relapse (CIR).

DESIGN

We searched 4 electronic databases from inception through March 2015 without language restriction and included studies in pediatric ALL or AML (0-21 y of age) reporting BMI as a predictor of survival or relapse. Higher BMI, defined as obese (≥95%) or overweight/obese (≥85%), was compared with lower BMI [nonoverweight/obese (<85%)]. Summary risk estimates for EFS, OS, and CIR (ALL only) were calculated with random- or fixed-effects models according to tests for between-study heterogeneity.

RESULTS

Of 4690 reports identified, 107 full-text articles were evaluated, with 2 additional articles identified via review of citations; 11 articles were eligible for inclusion in this meta-analysis. In ALL, we observed poorer EFS in children with a higher BMI (RR: 1.35; 95% CI: 1.20, 1.51) than in those at a lower BMI. A higher BMI was associated with significantly increased mortality (RR: 1.31; 95% CI: 1.09, 1.58) and a statistically nonsignificant trend toward greater risk of relapse (RR: 1.17; 95% CI: 0.99, 1.38) compared with a lower BMI. In AML, a higher BMI was significantly associated with poorer EFS and OS (RR: 1.36; 95% CI: 1.16, 1.60 and RR: 1.56; 95% CI: 1.32, 1.86, respectively) than was a lower BMI.

CONCLUSION

Higher BMI at diagnosis is associated with poorer survival in children with pediatric ALL or AML.