Postinduction dexamethasone and individualized dosing of Escherichia Coli L-asparaginase each improve outcome of children and adolescents with newly diagnosed acute lymphoblastic leukemia: results from a randomized study--Dana-Farber Cancer Institute ALL Consortium Protocol 00-01

Results and conclusions of the European Intergroup EURO-LB02 trial in children and adolescents with lymphoblastic lymphoma

In the European Intergroup EURO-LB02 trial, children and adolescents with lymphoblastic lymphoma underwent the non-Hodgkin lymphoma Berlin-Frankfurt-Münster protocol without prophylactic cranial radiotherapy. The primary aims of this trial were to test whether replacing prednisone with dexamethasone during induction increases event-free survival in the subgroups with T-cell lymphoblastic lymphoma and whether therapy duration could be reduced from 24 to 18 months (factorial design, randomizations). These questions could not be answered due to premature closure of the trial. Here we report on the secondary aims of the trial: whether the results of the NHL-BFM90 study could be reproduced and evaluation of disease features and prognostic factors. Three hundred and nineteen patients (66 with precursor B-cell lymphoblastic lymphoma, 233 with T-cell lymphoblastic lymphoma, 12 with mixed phenotype, 8 not classifiable) were enrolled. In induction, 215 patients received prednisone and 104 patients received dexamethasone. The median follow-up was 6.8 years (range, 3.0–10.3). The 5-year event-free survival was 82±2% [12 toxic deaths, 5 secondary malignancies, 43 non-response/relapse (central nervous system n=9; all received prednisone during induction)]. The event-free survival rate was 80±5% for patients with precursor B-cell lymphoblastic lymphoma, 82±3% for those with T-cell lymphoblastic lymphoma, and 100% for patients with a mixed phenotype. During induction, significantly more grade III/IV toxicities were observed in patients receiving dexamethasone, resulting in significant treatment delays. The number of toxic deaths did not differ significantly. The only variable associated with outcome was performance status at diagnosis. The 90% event-free survival rate for patients with T-cell lymphoblastic lymphoma shown in study NHL-BFM90 was not replicated, mainly due to more toxic deaths and central nervous system relapses. Dexamethasone in induction may prevent central nervous system relapse more effectively than prednisone but produces a higher burden of toxicity. (#NCT00275106).

Prolonged versus standard native E. coli asparaginase therapy in childhood acute lymphoblastic leukemia and non-Hodgkin lymphoma: final results of the EORTC-CLG randomized phase III trial 58951

Asparaginase is an essential component of combination chemotherapy for childhood acute lymphoblastic leukemia and non-Hodgkin lymphoma. The value of asparaginase was further addressed in a group of non-very high-risk patients by comparing prolonged (long-asparaginase) versus standard (short-asparaginase) native E. coli asparaginase treatment in a randomized part of the phase III 58951 trial of the European Organization for Research and Treatment of Cancer Children's Leukemia Group. The main endpoint was disease-free survival. Overall, 1,552 patients were randomly assigned to long-asparaginase (775 patients) or short-asparaginase (777 patients). Patients with grade ≥2 allergy to native E. coli asparaginase were switched to equivalent doses of Erwinia or pegylated E. coli asparaginase. The 8-year disease-free survival rate (±standard error) was 87.0±1.3% in the long-asparaginase group and 84.4±1.4% in the short-asparaginase group (hazard ratio: 0.87; P=0.33) and the 8-year overall survival rate was 92.6±1.0% and 91.3±1.2% respectively (hazard ratio: 0.89; P=0.53). An exploratory analysis suggested that the impact of long-asparaginase was beneficial in the National Cancer Institute standard-risk group with regards to disease-free survival (hazard ratio: 0.70; P=0.057), but far less so with regards to overall survival (hazard ratio: 0.89). The incidences of grade 3-4 infection during consolidation (25.2% versus 14.4%) and late intensification (22.6% versus 15.9%) and the incidence of grade 2-4 allergy were higher in the long-asparaginase arm (30% versus 21%). Prolonged native E. coli asparaginase therapy in consolidation and late intensification for our non-very high-risk patients did not improve overall outcome but led to an increase in infections and allergy. This trial was registered at www.clinicaltrials.gov as #NCT00003728.

Comparison of Native Escherichia coli L-Asparaginase versus Pegylated Asparaginase, in Combination with Ifosfamide, Methotrexate, Etoposide, and Prednisolone, in Extranodal NK/T-Cell Lymphoma, Nasal Type

Purpose

The aim of this study was to compare asparaginase-related toxicities in two asparaginase preparations, namely native Escherichia coli L-asparaginase (L-ASP) and pegylated asparaginase (PEG-ASP) in combination with ifosfamide, methotrexate, etoposide, and prednisolone (IMEP) in natural killer (NK)/T-cell lymphoma (NTCL).

Materials and Methods

A total of 41 NTCL patients who received IMEP plus native E. coli L-ASP or PEG-ASP at Seoul National University Hospital were included in this study between January 2013 and March 2016. IMEP/ASP treatment consisted of ifosfamide, methotrexate, etoposide, plus native E. coli L-ASP (6,000 IU/m² on days 1, 3, 5, 7, 9, and 11) or PEG-ASP (2,500 IU/m² on day 1) every 3 weeks. ASP-related toxicities, toxicity patterns, length of hospital stay, and clinical outcomes were compared between the different treatment groups.

Results

The frequency of ASP-related toxicities was similar between the IMEP plus native E. coli L-ASP group and the PEG-ASP group apart from hypofibrinogenemia (native E. coli L-ASP vs. PEG-ASP group, 86.4% vs. 36.8%; p=0.001). Although post-treatment transaminase and albumin levels were significantly high and low, respectively, hepatotoxicity gradients before and after treatment did not differ significantly between the groups. Since PEG-ASP was given at an outpatient clinic in some patients, length of hospital stay was significantly shorter in the IMEP plus PEG-ASP group (median, 4.0 vs. 6.0 days; p=0.002). A favorable tendency of clinical outcomes was observed in NTCL patients treated with IMEP plus PEG-ASP (complete remission rate, 73.7% vs. 45.5%; p=0.067).

Conclusion

IMEP plus PEG-ASP showed similar ASP-related toxicities, shorter length of hospital stay, and a trend towards improved clinical outcomes compared with IMEP plus native E. coli L-ASP in NTCL.

A thymidylate synthase polymorphism is associated with increased risk for bone toxicity among children treated for acute lymphoblastic leukemia

BACKGROUND

Bone fractures and osteonecrosis frequently complicate therapy for childhood acute lymphoblastic leukemia (ALL). Bone toxicity has been associated with exposure to corticosteroids and methotrexate (MTX) and age greater than 10 years. We tested whether common genetic polymorphisms were associated with bone toxicity during treatment for ALL.

PROCEDURE

A total of 615 of 794 children enrolled on Dana Farber Cancer Institute ALL Consortium protocol 05-001 (NCT00400946) met eligibility criteria for inclusion in this analysis. Nineteen candidate polymorphisms were selected a priori, targeting genes related to glucocorticoid metabolism, oxidative damage, and folate physiology. Polymorphisms were genotyped using either PCR-based allelic discrimination or PCR product length analysis.

RESULTS

Twenty percent of subjects were homozygous for two 28 bp repeats (2R/2R, where 2R is two 28-nucleotide repeats within the 5' untranslated region [UTR] of the thymidylate synthase [TS] gene) within the 5' UTR of the gene for TS. This 2R/2R genotype was associated with increased risk of osteonecrosis among children younger than 10 years at diagnosis (multivariable hazard ratio [HR] 2.71; 95% confidence interval [CI] 1.23-5.95; P = 0.013), and with bone fracture among children ≥ 10 years (multivariable HR 2.10; 95% CI 1.11-3.96; P = 0.022). No significant association was observed between TS genotype and red blood cell (RBC) folate, RBC MTX, or relapse risk.

CONCLUSIONS

A common genetic variant is associated with increased risk of osteonecrosis among children younger than 10 years at diagnosis and with bone fractures among older children. These findings suggest that children and adolescents with the 2R/2R TS genotype should be closely monitored for the development of bone toxicity during therapy for ALL, and support a clinical trial testing the efficacy of protective interventions specifically in this vulnerable population.

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.

Effective control of acute myeloid leukaemia and acute lymphoblastic leukaemia progression by telomerase specific adoptive T-cell therapy

Telomerase (TERT) is a ribonucleoprotein enzyme that preserves the molecular organization at the ends of eukaryotic chromosomes. Since TERT deregulation is a common step in leukaemia, treatments targeting telomerase might be useful for the therapy of hematologic malignancies. Despite a large spectrum of potential drugs, their bench-to-bedside translation is quite limited, with only a therapeutic vaccine in the clinic and a telomerase inhibitor at late stage of preclinical validation. We recently demonstrated that the adoptive transfer of T cell transduced with an HLA-A2-restricted T-cell receptor (TCR), which recognize human TERT with high avidity, controls human B-cell chronic lymphocytic leukaemia (B-CLL) progression without severe side-effects in humanized mice. In the present report, we show the ability of our approach to limit the progression of more aggressive leukemic pathologies, such as acute myeloid leukaemia (AML) and B-cell acute lymphoblastic leukaemia (B-ALL). Together, our findings demonstrate that TERT-based adoptive cell therapy is a concrete platform of T cell-mediated immunotherapy for leukaemia treatment.

Impact of Initial CSF Findings on Outcome Among Patients With National Cancer Institute Standard- and High-Risk B-Cell Acute Lymphoblastic Leukemia: A Report From the Children's Oncology Group

Purpose To determine the prognostic significance of blasts, and of white and red blood cells, in CSF samples at diagnosis of acute lymphoblastic leukemia (ALL), a uniform CSF and risk group classification schema was incorporated into Children's Oncology Group B-cell ALL (B-ALL) clinical trials. Methods CSF status was designated as follows: CNS1, no blasts; CNS2a to 2c, < 5 WBCs/μL and blasts with/without ≥ 10 RBCs/μL or ≥ 5 WBCs/μL plus blasts, with WBCs ≥ 5 times the number of RBCs; CNS3a to 3c, ≥ 5 WBCs/μL plus blasts with/without ≥ 10 RBCs/μL or clinical signs of CNS disease. CNS2 status did not affect therapy; patients with CNS3 status received two extra intrathecal treatments during induction and augmented postinduction therapy with 18 Gy of cranial radiation. Results Among 8,379 evaluable patients enrolled from 2004 to 2010, 7,395 (88.3%) had CNS1 status; 857 (10.2%), CNS2; and 127 (1.5%), CNS3. The 5-year event-free and overall survival rates were, respectively, 85% and 92.7% for CNS1, 76% and 86.8% for CNS2, and 76% and 82.1% for CNS3 ( P < .001). In multivariable analysis that included age, race/ethnicity, initial WBC, and day-29 minimal residual disease < 0.1%, CSF blast, regardless of cell count, was an independent adverse predictor of outcome for patients with standard- or high-risk disease according to National Cancer Institute criteria. The EFS difference reflected a significant difference in the incidence of CNS, not marrow, relapse in patients with CNS1 versus CNS2 and/or CNS3 status. Conclusion Low levels of CNS leukemia, regardless of RBCs, predict inferior outcome and higher rates of CNS relapse. These data suggest that additional augmentation of CNS-directed therapy is warranted for CNS2 disease.

Non-infectious chemotherapy-associated acute toxicities during childhood acute lymphoblastic leukemia therapy

During chemotherapy for childhood acute lymphoblastic leukemia, all organs can be affected by severe acute side effects, the most common being opportunistic infections, mucositis, central or peripheral neuropathy (or both), bone toxicities (including osteonecrosis), thromboembolism, sinusoidal obstruction syndrome, endocrinopathies (especially steroid-induced adrenal insufficiency and hyperglycemia), high-dose methotrexate-induced nephrotoxicity, asparaginase-associated hypersensitivity, pancreatitis, and hyperlipidemia. Few of the non-infectious acute toxicities are associated with clinically useful risk factors, and across study groups there has been wide diversity in toxicity definitions, capture strategies, and reporting, thus hampering meaningful comparisons of toxicity incidences for different leukemia protocols. Since treatment of acute lymphoblastic leukemia now yields 5-year overall survival rates above 90%, there is a need for strategies for assessing the burden of toxicities in the overall evaluation of anti-leukemic therapy programs.

Risk factors and treatment for steroid-related mood and behavior symptoms in preschool children with leukemia: A case series

Treatment of pediatric acute lymphoblastic leukemia (ALL) relies on systemic corticosteroids for remission; however, they can cause significant mood and behavior changes that interfere with quality of life and may increase risk for injury. This case series reports on preschool children with preexisting developmental and psychiatric risk factors who presented with behavioral side effects that required intervention. Identification of these vulnerable children may provide opportunities for early intervention, anticipatory guidance, and effective treatment to minimize behavioral side effects and improve quality of life and safety during ALL treatment.

Treatment for childhood acute lymphoblastic leukemia in Taiwan: Taiwan Pediatric Oncology Group ALL-2002 study emphasizing optimal reinduction therapy and central nervous system preventive therapy without cranial radiation

BACKGROUND

Reinduction therapy has improved the outcomes in children with acute lymphoblastic leukemia (ALL). We sought to determine the optimal course(s) of reinduction therapy for standard-risk (SR, or "low-risk" in other groups) patients. Also, we evaluated outcomes using triple intrathecal therapy without cranial radiation (CrRT) for central nervous system (CNS) preventive therapy.

PROCEDURE

From 2002 to 2012, all newly diagnosed children with ALL in Taiwan were enrolled in Taiwan Pediatric Oncology Group ALL-2002 protocol. SR patients were randomized to receive single or double reinduction courses. The patients enrolled before 2009 received CrRT, while those enrolled later did not. The Kaplan-Meier method was used to estimate survival rates and the difference between two groups was compared by the two-sided log-rank test.

RESULTS

In 1,366 eligible patients, the 5-year overall survival (OS) was 81.6 ± 1.1% (standard error) and 5-year event-free survival (EFS) was 74.3 ± 1.2%. In SR patients, the 5-year OS for one and two reinduction courses was 91.6 ± 2.1% and 93.7 ± 1.8%, respectively, and the 5-year EFS was 85.2 ± 2.7% and 89.8 ± 2.3%, respectively. There were no significant differences in survival between these two groups. Patients with MLL or BCR-ABL1 had the worst outcomes: 5-year EFS was 23.4 and 31.8% and 5-year OS was 28.6 and 44.7%, respectively. There was no significant difference in CNS relapse or survival between the era with or without CrRT.

CONCLUSIONS

For SR patients, one-course reinduction was adequate. Triple intrathecal therapy alone successfully prevented CNS relapse.

Consensus expert recommendations for identification and management of asparaginase hypersensitivity and silent inactivation

L-asparaginase is an integral component of therapy for acute lymphoblastic leukemia. However, asparaginase-related complications, including the development of hypersensitivity reactions, can limit its use in individual patients. Of considerable concern in the setting of clinical allergy is the development of neutralizing antibodies and associated asparaginase inactivity. Also problematic in the use of asparaginase is the potential for the development of silent inactivation, with the formation of neutralizing antibodies and reduced asparaginase activity in the absence of a clinically evident allergic reaction. Here we present guidelines for the identification and management of clinical hypersensitivity and silent inactivation with Escherichia coli- and Erwinia chrysanthemi- derived asparaginase preparations. These guidelines were developed by a consensus panel of experts following a review of the available published data. We provide a consensus of expert opinions on the role of serum asparaginase level assessment, indications for switching asparaginase preparation, and monitoring after change in asparaginase preparation.

Comparison of hypersensitivity rates to intravenous and intramuscular PEG-asparaginase in children with acute lymphoblastic leukemia: A meta-analysis and systematic review

BACKGROUND

Pegylated-asparaginase (PEG-ASP) is a critical treatment for pediatric acute lymphoblastic leukemia (ALL) and has traditionally been delivered via intramuscular (IM) injection. In an attempt to reduce pain and anxiety, PEG-ASP has increasingly been delivered via intravenous (IV) administration. The study objective was to perform a meta-analysis and systematic review to compare and generate pooled hypersensitivity rates for IM and IV PEG-ASP.

METHODS

A systematic literature search was conducted for all epidemiological studies that investigated IV and IM hypersensitivity rates for pediatric ALL. Included studies were critically appraised using the GRACE checklist. Pooled estimates and odds ratios with 95% confidence intervals (CIs) for IM and IV hypersensitivity rates were derived based on either a random or fixed effects model.

RESULTS

Four studies satisfied the inclusion criteria and were of adequate quality. The random effects pooled hypersensitivity rates were 23.5% (95% CI 14.7-33.7) and 8.7% (95% CI 5.4-12.8) for IV and IM, respectively. The fixed effects pooled odds ratio after adjusting for publication bias was 2.49 (95% CI 1.62-3.83), indicating a significantly higher risk of hypersensitivity for IV over IM PEG-ASP. This risk is far more pronounced for high-risk (HR) patients compared with standard-risk (SR) patients (IV vs. IM: HR ↑35.2% and SR ↓2.9%).

CONCLUSIONS

Although administering PEG-ASP through IV is preferable for patients, it poses a significantly higher risk of hypersensitivity when compared with IM administration, especially for HR patients. We recommend pediatric oncologists consider treating patients with HR pediatric ALL with IM PEG-ASP to reduce the risk of hypersensitivity.

Asparaginase-associated pancreatitis is not predicted by hypertriglyceridemia or pancreatic enzyme levels in children with acute lymphoblastic leukemia

BACKGROUND

l-Asparaginase is an important drug for treatment of childhood acute lymphoblastic leukemia (ALL), but is associated with serious toxicities, including pancreatitis and hypertriglyceridemia (HTG). Asparaginase-associated pancreatitis (AAP) is a common reason for stopping asparaginase treatment. The aim of this study was to explore if HTG or early elevations in pancreatic enzymes were associated with the subsequent development of AAP.

METHOD

Children (1.0-17.9 years) diagnosed with ALL, treated with asparaginase for 30 weeks, according to the NOPHO ALL2008 protocol at the University Hospital Rigshospitalet, Copenhagen, Denmark, were eligible. Pancreatic enzymes, triglycerides, and cholesterol were measured regularly.

RESULTS

Thirty-one patients were included. Seven patients were diagnosed with AAP. HTG was most evident when PEG-asparaginase and dexamethasone were administered concomitantly. Overall, there was no significant difference in triglyceride levels in patients who experienced AAP and patients who did not. An increase in triglyceride levels during concomitant dexamethasone therapy in delayed intensification was significantly associated with an increase in pancreas-specific amylase levels two weeks later (P = 0.005).

CONCLUSIONS

AAP does not seem to be associated with HTG. Continuous monitoring of pancreas enzymes does not predict AAP.

Allergic-like reactions to asparaginase: Atypical allergies without asparaginase inactivation

BACKGROUND

Asparaginase is an important component of pediatric acute lymphoblastic leukemia (ALL) therapy. Unfortunately, this treatment is hampered by hypersensitivity reactions. In general, allergies - regardless of severity - cause complete inactivation of the drug. However, we report atypical allergic reactions without inactivation of asparaginase, here called allergic-like reactions.

PROCEDURE

Patients with an allergic-like reaction, who were treated according to the Dutch Childhood Oncology Group ALL-11 or the CoALL 08-09 protocol, were described. The reactions were identified by continual measurement of asparaginase activity levels. Characteristics, including timing of occurrence, symptoms, grade, and the presence of antiasparaginase antibodies, were compared to those of real allergies.

RESULTS

Fourteen allergic-like reactions occurred in nine patients. Five reactions were to PEGasparaginase and nine to Erwinia asparaginase. Allergic-like reactions occurred relatively late after the start of infusion compared to real allergies. Antibodies were absent in all but one patient with an allergic-like reaction, while they were detected in all patients with a real allergy. Symptoms and grade did not differ between the groups. Asparaginase was continued with the same formulation in six patients of whom four finished treatment with adequate activity levels.

CONCLUSIONS

In conclusion, allergic-like reactions occur relatively late after the start of infusion and without antibodies. Despite these clinical differences, allergic-like reactions can only be distinguished from real allergies by continually measuring asparaginase activity levels. If clinically tolerated, formulations should not be switched in case of allergic-like reactions. Moreover, failure to recognize these reactions may lead to a less favorable prognosis if asparaginase therapy is terminated unnecessarily.

Clinical presentation and risk factors of serious infections in children with Down syndrome treated for acute lymphoblastic leukemia

BACKGROUND

Treatment of acute lymphoblastic leukemia (ALL) in children with Down syndrome (DS) is associated with a higher incidence of life-threatening infections compared to the overall pediatric population. The objective of this study was to describe infections and identify risk factors of microbiologically documented infections at a sterile site in children with DS during chemotherapy for ALL.

PROCEDURE

We conducted a single-institution retrospective review of infectious episodes encountered by patients with DS during primary treatment for ALL. Correlations between features of clinical presentation and severity of microbiologically proven infections were investigated.

RESULTS

Among 237 suspected infectious episodes encountered by 35 patients with DS and ALL (DS-ALL), a total of 40 episodes (16.9%) had the clinical presentation of a severe infection (SI). Seventeen patients had 33 (13.9%) microbiologically proven infections from a sterile site. Fever was not part of the clinical presentation in 27% of microbiologically documented infectious episodes. The odds ratio of a microbiologically proven infection at a sterile site was significantly increased during a 7-day interval after treatment with glucocorticoids (2.18; 95% CI: 1.02-4.66; P = 0.04). Neither administration of anthracyclines in the preceding 14 days nor neutropenia correlated with infections.

CONCLUSIONS

Serious infections in DS-ALL may present without typical signs such as fever. The immediate time period following administration of glucocorticoids is particularly associated with the risk of SIs.

Osteonecrosis in children with acute lymphoblastic leukemia

The morbidity and toxicity associated with current intensive treatment protocols for acute lymphoblastic leukemia in childhood become even more important as the vast majority of children can be cured and become long-term survivors. Osteonecrosis is one of the most common therapy-related and debilitating side effects of anti-leukemic treatment and can adversely affect long-term quality of life. Incidence and risk factors vary substantially between study groups and therapeutic regimens. We therefore analyzed 22 clinical trials of childhood acute lymphoblastic leukemia in terms of osteonecrosis incidence and risk factors. Adolescent age is the most significant risk factor, with patients >10 years old at the highest risk. Uncritical modification or even significant reduction of glucocorticoid dosage cannot be recommended at this stage. A novel and innovative approach to reduce osteonecrosis-associated morbidity might be systematic early screening for osteonecrosis by serial magnetic resonance images. However, discriminating patients at risk of functional impairment and debilitating progressive joint disease from asymptomatic patients still remains challenging.

Improvement of the Outcome of Relapsed or Refractory Acute Lymphoblastic Leukemia in Children Using a Risk-Based Treatment Strategy

Relapsed/refractory acute lymphoblastic leukemia (ALL) is a leading cause of death by cancer in children. Our institution has switched relapse treatment strategy to improve survival. We reviewed records of first relapse/refractory childhood ALL between 1996 and 2012. Based on length of first remission, relapse site and immunophenotype, patients were classified into two groups: standard-risk relapse (SRR) and high-risk relapse and refractory (HRRR). Before 2007, all patients were uniformly treated with the same induction as at presentation, followed by hematopoietic stem cell transplantation (HSCT). Since 2007, treatment was given according to risk of failure: SRR were mostly treated with chemotherapy; HRRR patients underwent HSCT after intensive chemotherapy, aiming reduction of pre-transplant disease burden. Sixty-four patients were included. Thirty (47%) were SRR and 34 (53%) HRRR, including 11 with refractory ALL. Five-years overall survival (OS) and event-free survival (EFS) were similar for SRR, but were significantly higher with new risk-based strategy for HRRR: 56% versus 17% (P = 0.03) for OS, and 56% vs 11% for EFS (P = 0.008), respectively. In multivariate analysis, treatment strategy was significantly associated with survival. In conclusion, change for a risk-based strategy in our institution increased survival of high-risk patients to levels similar of those of standard-risk patients.

Serial Ultrasound Monitoring for Early Recognition of Asparaginase Associated Pancreatitis in Children With Acute Lymphoblastic Leukemia

BACKGROUND

Acute lymphoblastic leukemia (ALL) is the most common cancer in children and L-asparaginase is an essential component of the treatment. Cessation of L-asparaginase decreases event free survival. Acute pancreatitis is the toxicity that most commonly results in cessation of L-asparaginase. We tested whether serial ultrasound examinations could predict asparaginase-associated pancreatitis (AAP).

METHODS

Children (aged 1.0-17.9 years) with childhood ALL treated at the University Hospital Rigshopitalet, Copenhagen, according to the standard or intermediate risk arms of the NOPHO ALL2008 protocol, with PEG-asparaginase of 2 or 6 week intervals, for 30 weeks had their pancreas monitored using serial ultrasound in order to detect early signs of inflammation.

RESULTS

Nineteen of 31 eligible patients were included. Three of the included patients developed AAP. None of the patients, including the three patients that developed AAP, had signs of inflammatory edema or pancreas enzymes above three times the upper normal limit prior to AAP.

CONCLUSION

We found no signs of inflammatory edema within the pancreas on ultrasound during treatment with PEG-asparginase in our cohort prior to development of AAP or in patients that did not develop AAP.

Racial disparities in the survival of American children, adolescents, and young adults with acute lymphoblastic leukemia, acute myelogenous leukemia, and Hodgkin lymphoma

BACKGROUND

Race-based survival in children and adolescents with hematologic malignancies has been a national challenge for decades. Large-scale investigations of age- and race-based survival trends over time in these patients have not previously been reported. The objective of this study was to investigate whether race- and age-related differences in pediatric and adolescent and young adult (AYA) leukemia and lymphoma survival persist and to what extent these differences have changed over time.

METHODS

Using the Surveillance, Epidemiology, and End Results program, this study investigated the outcomes of black and white (1975-2012; n = 27,369) and white and Hispanic (1992-2012; n = 20,574) children (0-14 years old) and AYAs (15-39 years old) with acute lymphoblastic leukemia (ALL), acute myelogenous leukemia (AML), and Hodgkin lymphoma (HL). Estimates of 5- and 10-year relative survival were compared over time.

RESULTS

Trends showed a convergence of survival for white and black children with ALL but a divergence in survival for AYA patients. Hispanic children and AYAs both suffered inferior outcomes. Trends for AML revealed persistent survival differences between black and white children and suggested worsening disparities for AYAs. Survival trends in HL revealed sustained survival differences between black and white AYA patients, whereas no differences were found in Hispanic and white patient outcomes for AML or HL.

CONCLUSIONS

Although survival for children and AYAs with ALL, AML, and HL has improved over the past 4 decades, differences persist between black, white, and Hispanic children and AYAs; survival disparities between black and white children with ALL have been nearly eliminated. Strategies aimed at identifying causality and reducing disparities are warranted. Cancer 2016. © 2016 American Cancer Society. Cancer 2016;122:2723-2730. © 2016 American Cancer Society.

The use of Erwinia asparaginase for adult patients with acute lymphoblastic leukemia after pegaspargase intolerance

Asparaginase administration has become a crucial component of front-line pediatric and pediatric-insipired multi-agent regimens for the treatment of acute lymphoblastic leukemia (ALL). The aim of this retrospective study was to assess the safety and feasibility of switching to Erwinia asparaginase after pegaspargase intolerance in adult ALL patients treated at Memorial Sloan Kettering Cancer Center. Our analysis included 10 patients, with a median age of 39 years (range 20-72), male predominance (90%), and a typical B-cell to T-cell ratio (70:30%) for ALL. Nine patients were switched to Erwinia asparaginase after pegaspargase hypersensitivity and one patient after grade 4 hyperbilirubinemia secondary to pegaspargase. With Erwinia asparaginase, no hypersensitivity reactions occurred and no patient developed other known clinical asparaginase-related toxicities. Laboratory adverse effects consisted of mostly mild elevation in liver enzymes. No morphologic relapses have occurred in any patient switched to Erwinia asparaginase in first remission at a follow up of 0.4-34.6 months. These findings are unique in that all of our patients received Erwinia asparaginase after hypersensitivity or intolerance to pegaspargase and 50% of them were older than 40 years of age, a population with very limited Erwinia asparaginase data. Our observations provide preliminary information that treatment with Erwinia asparaginase can proceed as scheduled in adult patients, despite pegaspargase hypersensitivity and possibly liver intolerance.

A 10-Year Follow-up Survey of Treatment Abandonment of Children With Acute Myeloid Leukemia in Suzhou, China

A survey of the clinical data on acute myeloid leukemia (AML) over the past 10 years in the treatment center of Children's Hospital was presented. The aim of the study was to identify the factors influencing the treatment abandonment rate (AR) of AML. Of the 474 AML cases examined, 264 were abandoned (55.7%). The most important factor affecting AR appeared to be the AML subtype-that is, the M3 versus non-M3 (42% vs. 60%). Patient age was observed to be closely related to AR-the older the patients, the lower the AR-and infants had the highest prevalence of abandonment (84.2%). The patient's residential location was markedly correlated to AR, which was almost inversely proportional to the size of the township where the patient came from. From large cities, intermediate and small towns to countryside villages, the AR increased linearly. So was the correlation with health insurance coverage, which decreased in the same way. Sex and karyotypes did not affect AR. In conclusion, the patients' financial burden and the perceived incurability of AML were the 2 leading factors dominating the decision for abandonment in parents and caregivers.

Prophylactic Trimethoprim-Sulfamethoxazole Does Not Affect Pharmacokinetics or Pharmacodynamics of Methotrexate

Trimethoprim-sulfamethoxazole (TMP/SMX) is used as prophylaxis against Pneumocystis jiroveci during chemotherapy. Many groups recommend withholding TMP/SMX during high-dose methotrexate (HDMTX) for concerns that it will delay methotrexate clearance. We compared methotrexate exposure following HDMTX (NCT00549848) in 424 patients including 783 courses that were given concurrently and 602 courses that were not given concurrently with TMP/SMX. Among 176 patients (555 courses) on the low-risk arm (HDMTX=2.5 g/m/24 h), there was no difference in clearance (110.7 [1.8%] vs. 108.2 [0.9%] mL/min/m, P=0.3) nor in 42 hour methotrexate concentration (0.37 [5.1%] vs. 0.40 (5.0%) μM, P=0.23). Among 248 patients (830 courses) on the standard/high-risk arm (HDMTX ~5 g/m/24 h), there was slightly higher clearance (95.5 [1.4%] vs. 91.2 [0.8%] mL/min/m, P=0.005) in those receiving TMP/SMX, with no difference in the 42 hour methotrexate concentration (0.59 [4.1%] vs. 0.66 [4.2%] μM, P=0.06). There was no difference in neutrophil counts based on TMP/SMX during HDMTX (P=0.83). TMP/SMX also did not have a significant impact on myelosuppression of low-dose methotrexate (40 mg/m) given during continuation therapy among 230 patients enrolled on a prior study (NCT00137111). Thus, we found no evidence for an interaction between methotrexate and TMP/SMX given prophylactically.

L-asparaginase in the treatment of patients with acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is a hematologic malignancy that predominantly occurs in children between 2 and 10 years of age. L-asparaginase is an integral component of treatment for patients with ALL and since its introduction into pediatric treatment protocols in the 1960s, survival rates in children have progressively risen to nearly 90%. Outcomes for adolescent and young adult (AYA) patients, aged 15-39 years and diagnosed with ALL, have historically been less favorable. However, recent reports suggest substantially increased survival in AYA patients treated on pediatric-inspired protocols that include a greater cumulative dose of asparaginase. All  currently available asparaginases share the same mechanism of action - the deamination and depletion of serum asparagine levels - yet each displays a markedly different pharmacokinetic profile. Pegylated asparaginase derived from the bacterium Escherichia coli is used as first-line therapy; however, up to 30% of patients develop a treatment-limiting hypersensitivity reaction. Patients who experience a hypersensitivity reaction to an E. coli-derived asparaginase can continue treatment with Erwinia chrysanthemi asparaginase. Erwinia asparaginase is immunologically distinct from E. coli-derived asparaginases and exhibits no cross-reactivity. Studies have shown that with adequate dosing, therapeutic levels of Erwinia asparaginase activity can be achieved, and patients switched to Erwinia asparaginase due to hypersensitivity can obtain outcomes similar to patients who do not experience a hypersensitivity reaction. Therapeutic drug monitoring may be required to ensure that therapeutic levels of asparaginase activity are maintained.

Immunology of infusion reactions in the treatment of patients with acute lymphoblastic leukemia

Infusion reactions are potentially dose-limiting adverse events associated with intravenous administration of several common agents used to treat patients with acute lymphoblastic leukemia. True clinical hypersensitivity reactions are antibody-mediated and can occur only after repeated exposure to an antigen. Conversely, anaphylactoid infusion reactions are nonantibody-mediated and often occur on the initial exposure to a drug. Cytokine-release syndrome comprises a subset of nonantibody-mediated infusion reactions associated with the use of monoclonal antibodies and immune therapies. Clinical symptoms of hypersensitivity reactions and nonantibody-mediated infusion reactions heavily overlap and can be difficult to distinguish in practice. Regardless of the underlying mechanism, any infusion reaction can negatively affect treatment efficacy and patient safety. These events require prompt response, and potentially, modification of subsequent therapy.

Impact of Socioeconomic Status on Timing of Relapse and Overall Survival for Children Treated on Dana-Farber Cancer Institute ALL Consortium Protocols (2000-2010)

BACKGROUND

Population-based evidence suggests that lower socioeconomic status (SES) negatively impacts the overall survival (OS) of children with leukemia; however, the relationships between SES and treatment-related mortality, relapse, and timing of relapse remain unclear.

PROCEDURE

We examined OS, event-free survival (EFS) and cumulative incidence (CI) and timing of relapse by community-level poverty for 575 children aged 1-18 years with newly diagnosed acute lymphoblastic leukemia (ALL) treated on consecutive phase III multicenter Dana-Farber Cancer Institute ALL Consortium Protocols between 2000 and 2010. Children were categorized into high- and low-poverty areas for the analysis using aggregate U.S. Census data linked to zip code.

RESULTS

Children living in high-poverty areas experienced a 5-year OS of 85% as compared with 92% for those in low-poverty areas (P = 0.02); poverty remained marginally significant (P = 0.07) after adjustment for immunophenotype, age, and white blood cell count. There were no differences detected in EFS or CI relapse by poverty area. However, 92% of the relapses observed in children from high-poverty areas occurred <36 months from complete remission, compared to 48% of those in children from low-poverty areas (P = 0.008).

CONCLUSIONS

U.S. children with ALL living in high-poverty areas have a higher risk of early relapse when compared with those living in low-poverty areas despite uniform treatment. This may in part explain decreased OS observed in these children. This finding highlights disparities in childhood cancer outcomes by SES despite uniform treatment. Further investigations of the mechanistic pathways underlying this finding are needed.

Erythrocyte encapsulated l-asparaginase (GRASPA) in acute leukemia

l-asparaginase, an enzyme originally derived from Escherichia coli, represents a major drug in the treatment of acute lymphoblastic leukemia. However, the occurrence of major adverse effects often leads to early withdrawal of the enzyme. Main side effects include immune-allergic reactions, coagulopathy, pancreatitis and hepatic disorders. Novel asparaginase formulations and alternative sources have been developed to address this issue, but the results were not totally satisfactory. l-asparaginase loaded red blood cells (RBCs; GRASPA) represent a new asparaginase presentation with reduced immunological adverse reactions. RBCs protect l-asparaginase, enhance its half-life and reduce the occurrence of adverse events. We reviewed the history, biology and clinical experiences with l-asparaginase, and the characteristics and first clinical experiences with GRASPA in the treatment of acute leukemia.

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.

Clinical and Genetic Risk Factors for Acute Pancreatitis in Patients With Acute Lymphoblastic Leukemia

PURPOSE

Acute pancreatitis is one of the common causes of asparaginase intolerance. The mechanism is unknown, and genetic predisposition to asparaginase-induced pancreatitis has not been previously identified.

METHODS

To determine clinical risk factors for asparaginase-induced pancreatitis, we studied a cohort of 5,185 children and young adults with acute lymphoblastic leukemia, including 117 (2.3%) who were diagnosed with at least one episode of acute pancreatitis during therapy. A genome-wide association study was performed in the cohort and in an independent case-control group of 213 patients to identify genetic risk factors.

RESULTS

Risk factors associated with pancreatitis included genetically defined Native American ancestry (P < .001), older age (P < .001), and higher cumulative dose of asparaginase (P < .001). No common variants reached genome-wide significance in the genome-wide association study, but a rare nonsense variant rs199695765 in CPA2, encoding carboxypeptidase A2, was highly associated with pancreatitis (hazard ratio, 587; 95% CI, 66.8 to 5166; P = 9.0 × 10(-9)). A gene-level analysis showed an excess of additional CPA2 variants in patients who did versus those who did not develop pancreatitis (P = .001). Sixteen CPA2 single-nucleotide polymorphisms were associated (P < .05) with pancreatitis, and 13 of 24 patients who carried at least one of these variants developed pancreatitis. Biologic functions that were overrepresented by common variants modestly associated with pancreatitis included purine metabolism and cytoskeleton regulation.

CONCLUSION

Older age, higher exposure to asparaginase, and higher Native American ancestry were independent risk factors for pancreatitis in patients with acute lymphoblastic leukemia. Those who inherit a nonsense rare variant in the CPA2 gene had a markedly increased risk of asparaginase-induced pancreatitis.

Incidence and risk factors for Central Nervous System thrombosis in paediatric acute lymphoblastic leukaemia during intensive asparaginase treatment: a single-centre cohort study

Central Nervous System (CNS) thrombosis is a complication of acute lymphoblastic leukaemia (ALL) treatment that is potentially associated with significant morbidity and neurological sequelae. Its presumably multifactorial aetiology is poorly characterized. We conducted a single-centre, retrospective cohort study on 346 ALL paediatric patients (1-16 years old) treated with asparaginase intensive Dana Farber Cancer Institute (DFCI) protocols from 1998 to 2011. The incidence, risk factors and outcome of CNS thrombosis were evaluated. CNS thrombosis occurred in 3·8% (13/346) of the patients (95% confidence interval 2·0-6·3%). Twelve events were diagnosed during intensification, all of which resolved within 2 weeks without neurological sequelae or significant impact in survival. Obesity (body mass index above 95th percentile) and asparaginase formulation were the only factors associated with CNS thrombosis, with an increase in the odds of event in obese patients [odds ratio (OR) = 3·37; P = 0·064] and a reduction in patients receiving Erwinia asparaginase (OR = 0·12; P = 0·018). No association could be demonstrated for age, gender, DFCI risk-group, ALL phenotype, steroid or doxorubicin use, central venous line use or CNS radiotherapy. CNS thrombosis is a rare but manageable adverse event without significant sequelae or detrimental effects in survival. Increased awareness is recommended in obese patients particularly during intensive asparaginase use.

Asparaginase Potentiates Glucocorticoid-Induced Osteonecrosis in a Mouse Model

Osteonecrosis is a common dose-limiting toxicity of glucocorticoids. Data from clinical trials suggest that other medications can increase the risk of glucocorticoid-induced osteonecrosis. Here we utilized a mouse model to study the effect of asparaginase treatment on dexamethasone-induced osteonecrosis. Mice receiving asparaginase along with dexamethasone had a higher rate of osteonecrosis than those receiving only dexamethasone after 6 weeks of treatment (44% vs. 10%, P = 0.006). Similarly, epiphyseal arteriopathy, which we have shown to be an initiating event for osteonecrosis, was observed in 58% of mice receiving asparaginase and dexamethasone compared to 17% of mice receiving dexamethasone only (P = 0.007). As in the clinic, greater exposure to asparaginase was associated with greater plasma exposure to dexamethasone (P = 0.0001). This model also recapitulated other clinical risk factors for osteonecrosis, including age at start of treatment, and association with the systemic exposure to dexamethasone (P = 0.027) and asparaginase (P = 0.036). We conclude that asparaginase can potentiate the osteonecrotic effect of glucocorticoids.

Influence of Cranial Radiotherapy on Outcome in Children With Acute Lymphoblastic Leukemia Treated With Contemporary Therapy

PURPOSE

We sought to determine whether cranial radiotherapy (CRT) is necessary to prevent relapse in any subgroup of children with acute lymphoblastic leukemia (ALL).

PATIENTS AND METHODS

We obtained aggregate data on relapse and survival outcomes for 16,623 patients age 1 to 18 years old with newly diagnosed ALL treated between 1996 and 2007 by 10 cooperative study groups from around the world. The proportion of patients eligible for prophylactic CRT varied from 0% to 33% by trial and was not related to the proportion eligible for allogeneic stem-cell transplantation in first complete remission. Using a random effects model, with CRT as a dichotomous covariate, we performed a single-arm meta-analysis to compare event-free survival and cumulative incidence of isolated or any CNS relapse and isolated bone marrow relapse in high-risk subgroups of patients who either did or did not receive CRT.

RESULTS

Although there was significant heterogeneity in all outcome end points according to trial, CRT was associated with a reduced risk of relapse only in the small subgroup of patients with overt CNS disease at diagnosis, who had a significantly lower risk of isolated CNS relapse (4% with CRT v 17% without CRT; P = .02) and a trend toward lower risk of any CNS relapse (7% with CRT v 17% without CRT; P = .09). However, this group had a relatively high rate of events regardless of whether or not they received CRT (32% [95% CI, 26% to 39%] v 34% [95% CI, 19% to 54%]; P = .8).

CONCLUSION

CRT does not have an impact on the risk of relapse in children with ALL treated on contemporary protocols.

Asparaginase-associated toxicity in children with acute lymphoblastic leukemia

Asparaginase is an integral component of multiagent chemotherapy regimens for the treatment of children with acute lymphoblastic leukemia. Positive outcomes are seen in patients who are able to complete their entire prescribed course of asparaginase therapy. Toxicities associated with asparaginase use include hypersensitivity (clinical and subclinical), pancreatitis, thrombosis, encephalopathy, and liver dysfunction. Depending on the nature and severity of the toxicity, asparaginase therapy may be altered or discontinued in some patients. Clinical hypersensitivity is the most common asparaginase-associated toxicity requiring treatment discontinuation, occurring in up to 30% of patients receiving Escherichia coli-derived asparaginase. The ability to rapidly identify and manage asparaginase-associated toxicity will help ensure patients receive the maximal benefit from asparaginase therapy. This review will provide an overview of the common toxicities associated with asparaginase use and recommendations for treatment management.

Intravenous pegylated asparaginase versus intramuscular native Escherichia coli L-asparaginase in newly diagnosed childhood acute lymphoblastic leukaemia (DFCI 05-001): a randomised, open-label phase 3 trial

BACKGROUND

l-asparaginase is a universal component of treatment for childhood acute lymphoblastic leukaemia, and is usually administered intramuscularly. Pegylated Escherichia coli asparaginase (PEG-asparaginase) has a longer half-life and is potentially less immunogenic than the native Escherichia coli (E coli) preparation, and can be more feasibly administered intravenously. The aim of the Dana-Farber Cancer Institute Acute Lymphoblastic Leukaemia Consortium Protocol 05-001 (DFCI 05-001) was to compare the relative toxicity and efficacy of intravenous PEG-asparaginase and intramuscular native E colil-asparaginase in children with newly diagnosed acute lymphoblastic leukaemia.

METHODS

DFCI 05-001 enrolled patients aged 1-18 years with newly diagnosed acute lymphoblastic leukaemia from 11 consortium sites in the USA and Canada. Patients were assigned to an initial risk group on the basis of their baseline characteristics and then underwent 32 days of induction therapy. Those who achieved complete remission after induction therapy were assigned to a final risk group and were eligible to participate in a randomised comparison of intravenous PEG-asparaginase (15 doses of 2500 IU/m(2) every 2 weeks) or intramuscular native E colil-asparaginase (30 doses of 25 000 IU/m(2) weekly), beginning at week 7 after study entry. Randomisation (1:1) was unmasked, and was done by a statistician-generated allocation sequence using a permuted blocks algorithm (block size of 4), stratified by final risk group. The primary endpoint of the randomised comparison was the overall frequency of asparaginase-related toxicities (defined as allergy, pancreatitis, and thrombotic or bleeding complications). Predefined secondary endpoints were disease-free survival, serum asparaginase activity, and quality of life during therapy as assessed by PedsQL surveys. All analyses were done by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00400946.

FINDINGS

Between April 22, 2005, and Feb 12, 2010, 551 eligible patients were enrolled. 526 patients achieved complete remission after induction, of whom 463 were randomly assigned to receive intramuscular native E colil-asparaginase (n=231) or intravenous PEG-asparaginase (n=232). The two treatment groups did not differ significantly in the overall frequency of asparaginase-related toxicities (65 [28%] of 232 patients in the intravenous PEG-asparaginase group vs 59 [26%] of 231 patients in the intramuscular native E colil-asparaginase group, p=0·60), or in the individual frequency of allergy (p=0·36), pancreatitis (p=0·55), or thrombotic or bleeding complications (p=0·26). Median follow-up was 6·0 years (IQR 5·0-7·1). 5-year disease-free survival was 90% (95% CI 86-94) for patients assigned to intravenous PEG-asparaginase and 89% (85-93) for those assigned to intramuscular native E colil-asparaginase (p=0·58). The median nadir serum asparaginase activity was significantly higher in patients who received intravenous PEG-asparaginase than in those who received intramuscular native E colil-asparaginase. Significantly more anxiety was reported by both patients and parent-proxy in the intramuscular native E colil-asparaginase group than in the intravenous PEG-asparaginase group. Scores for other domains were similar between the groups. The most common grade 3 or worse adverse events were bacterial or fungal infections (47 [20%] of 232 in the intravenous PEG-asparaginase group vs 51 [22%] of 231 patients in the intramuscular E colil-asparaginase group) and asparaginase-related allergic reactions (14 [6%] vs 6 [3%]).

INTERPRETATION

Intravenous PEG-asparaginase was not more toxic than, was similarly efficacious to, and was associated with decreased anxiety compared with intramuscular native E colil-asparaginase, supporting its use as the front-line asparaginase preparation in children with newly diagnosed acute lymphoblastic leukaemia.

FUNDING

National Cancer Institute and Enzon Pharmaceuticals.

Asparaginase Therapy in Pediatric Acute Lymphoblastic Leukemia: A Focus on the Mode of Drug Resistance

Asparaginase is one of the most important chemotherapeutic agents against pediatric acute lymphoblastic leukemia (ALL), the most common form of childhood cancer. The therapeutic efficacy (e.g., chemoresistance) and adverse effects of asparaginase (e.g., hypersensivity and pancreatitis) have been investigated over the past four decades. It was suggested early on that leukemic cells are resistant to asparaginase because of their increased asparagine synthetase activity. Afterward, other mechanisms associated with asparaginase resistance were reported. Not only leukemic cells but also patients themselves may play a role in causing asparaginase resistance, which has been associated with unfavorable outcome in children with ALL. This article will briefly review asparaginase therapy in children with ALL and comprehensively analyze recent reports on the potential mechanisms of asparaginase resistance.

Best Practices in Adolescent and Young Adult Patients with Acute Lymphoblastic Leukemia: A Focus on Asparaginase

The inclusion of asparaginase in chemotherapy regimens to treat acute lymphoblastic leukemia (ALL) has had a positive impact on survival in pediatric patients. Historically, asparaginase has been excluded from most treatment protocols for adolescent and young adult (AYA) patients because of perceived toxicity in this population, and this is believed to have contributed to poorer outcomes in these patients. However, retrospective analyses over the past 12 years have shown that 2-, 5-, and 7-year overall survival of AYA patients is significantly improved with pediatric versus adult protocols. The addition of asparaginase to adult protocols yielded high rates of first remission and improved survival. However, long-term survival remains lower compared with what has been seen in pediatrics. The notion that asparaginase is poorly tolerated by AYA patients has been challenged in multiple studies. In some, but not all, studies, the incidences of hepatic and pancreatic toxicities were higher in AYA patients, whereas the rates of hypersensitivity reactions did not appear to differ with age. There is an increased risk of venous thromboembolic events, and management with anti-coagulation therapy is recommended. Overall, the risk of therapy-related mortality is low. Together, this suggests that high-intensity pediatric protocols offer an effective and tolerable approach to treating ALL in the AYA population.

Childhood Acute Lymphoblastic Leukemia: Progress Through Collaboration

PURPOSE

To review the impact of collaborative studies on advances in the biology and treatment of acute lymphoblastic leukemia (ALL) in children and adolescents.

METHODS

A review of English literature on childhood ALL focusing on collaborative studies was performed. The resulting article was reviewed and revised by the committee chairs of the major ALL study groups.

RESULTS

With long-term survival rates for ALL approaching 90% and the advent of high-resolution genome-wide analyses, several international study groups or consortia were established to conduct collaborative research to further improve outcome. As a result, treatment strategies have been improved for several subtypes of ALL, such as infant, MLL-rearranged, Philadelphia chromosome-positive, and Philadelphia chromosome-like ALL. Many recurrent genetic abnormalities that respond to tyrosine kinase inhibitors and multiple genetic determinants of drug resistance and toxicities have been identified to help develop targeted therapy. Several genetic polymorphisms have been recognized that show susceptibility to developing ALL and that help explain the racial/ethnic differences in the incidence of ALL.

CONCLUSION

The information gained from collaborative studies has helped decipher the heterogeneity of ALL to help improve personalized treatment, which will further advance the current high cure rate and the quality of life for children and adolescents with ALL.