Early Intensification of Intrathecal Chemotherapy Virtually Eliminates Central Nervous System Relapse in Children With Acute Lymphoblastic Leukemia

Treatment outcomes in childhood acute lymphoblastic leukemia: 40-year experience from a single tertiary center in Thailand

Studies on the long-term treatment outcomes of childhood acute lymphoblastic leukemia (ALL) in resource-limited countries are scarce. The purpose of this study was to assess the evolution of survival outcomes of pediatric ALL in a tertiary care center in Thailand over a 40-year period. We retrospectively reviewed the medical records of pediatric patients who were diagnosed with ALL and treated at our center between June 1979 and December 2019. We classified the patients into 4 study periods depending on the therapy protocol used to treat the patients (period 1: 1979-1986, period 2: 1987-2005, period 3: 2006-2013, and period 4: 2014-2019). The Kaplan-Meier method was used to determine overall and event-free survival (EFS) for each group. The log-rank test was used to identify statistical differences. Over the study period, 726 patients with ALL were identified, 428 boys (59%) and 298 girls (41%), with a median age at diagnosis of 4.7 years (range: 0.2-15 years). The study periods 1, 2, 3, and 4 had 5-year EFS rates of 27.6%, 41.6%, 55.9%, and 66.4%, and 5-year overall survival (OS) rates of 32.8%, 47.8%, 61.5%, and 69.3%, respectively. From periods 1 to 4, both the EFS and OS rates increased significantly (p <. 0001). Age, study period, and white blood cell (WBC) count were all significant prognostic indicators for survival outcomes. The OS of patients with ALL treated in our center improved significantly over time from 32.8% in period 1 to 69.3% in period 4.

Molecular Mechanisms of ARID5B-Mediated Genetic Susceptibility to Acute Lymphoblastic Leukemia

BACKGROUND

There is growing evidence for the inherited basis of susceptibility to childhood acute lymphoblastic leukemia (ALL). Genome-wide association studies have identified non-coding ALL risk variants at the ARID5B gene locus, but their exact functional effects and the molecular mechanism linking ARID5B to B-cell ALL leukemogenesis remain largely unknown.

METHODS

We performed targeted sequencing of ARID5B in germline DNA of 5008 children with ALL. Variants were evaluated for association with ALL susceptibility using 3644 patients from the UK10K cohort as non-ALL controls, under an additive model. Cis-regulatory elements in ARID5B were systematically identified using dCas9-KRAB-mediated enhancer interference system enhancer screen in ALL cells. Disruption of transcription factor binding by ARID5B variant was predicted informatically and then confirmed using chromatin immunoprecipitation and coimmunoprecipitation. ARID5B variant association with hematological traits was examined using UK Biobank dataset. All statistical tests were 2-sided.

RESULTS

We identified 54 common variants in ARID5B statistically significantly associated with leukemia risk, all of which were noncoding. Six cis-regulatory elements at the ARID5B locus were discovered using CRISPR-based high-throughput enhancer screening. Strikingly, the top ALL risk variant (rs7090445, P = 5.57 × 10-45) is located precisely within the strongest enhancer element, which is also distally tethered to the ARID5B promoter. The variant allele disrupts the MEF2C binding motif sequence, resulting in reduced MEF2C affinity and decreased local chromosome accessibility. MEF2C influences ARID5B expression in ALL, likely via a transcription factor complex with RUNX1. Using the UK Biobank dataset (n = 349 861), we showed that rs7090445 was also associated with lymphocyte percentage and count in the general population (P = 8.6 × 10-22 and 2.1 × 10-18, respectively).

CONCLUSIONS

Our results indicate that ALL risk variants in ARID5B function by modulating cis-regulatory elements at this locus.

St. Jude Total Therapy studies from I to XVII for childhood acute lymphoblastic leukemia: a brief review

The therapy design of childhood acute lymphoblastic leukemia (ALL) has evolved over the past 60 years. The St. Jude Children's Research Hospital has developed 17 treatment protocols from 1962 to 2017, aiming to have the most effective and least toxic treatment form. This review summarizes each protocol's objectives, inclusion criteria, treatment phases, pharmacological agents, irradiation therapy, response criteria, risk stratification, type of relapse, and overall survival. The enhancement and successful application of preventive therapy for ALL and following a risk-stratified approach have progressively improved the cure rate of childhood ALL, with relatively few adverse sequelae. Moreover, St. Jude's scientific theme serves as a reminder of the principal factor of research directed to a catastrophic disease such as ALL.

Central Nervous System Involvement in Adults with Acute Leukemia: Diagnosis, Prevention, and Management

PURPOSE OF REVIEW

Recent treatment advances in both acute myeloid leukemia and acute lymphoblastic leukemia have drastically improved outcomes for these diseases, but central nervous system (CNS) relapses still occur. Treatment of CNS disease can be challenging due to the impermeability of the blood-brain barrier to many systemic therapies.

RECENT FINDINGS

The diagnosis of CNS leukemia relies on assessment of clinical symptoms, cerebrospinal fluid sampling for conventional cytology and/or flow cytometry, and neuroimaging. While treatment of CNS leukemia with systemic or intrathecal chemotherapy and/or radiation can be curative in some patients, these modalities can also lead to serious toxicities. In the modern era, prophylaxis with intrathecal chemotherapy is the most important strategy to prevent CNS relapses in high risk patients. Accurate risk stratification tools and the use of risk-adapted prophylactic therapy are imperative to improving the outcomes of patients with acute leukemias and preventing the development of CNS leukemia.

Pharmacogenetics of the Central Nervous System-Toxicity and Relapse Affecting the CNS in Pediatric Acute Lymphoblastic Leukemia

Simple Summary

Despite recent improvements in cure rates, pediatric acute lymphoblastic leukemia (ALL) patients remain at risk to develop relapse disease or suffer from therapy-associated side effects. Over 5% of adverse events appear in the central nervous system (CNS) and can impact survival or quality of life of the patients. Inherited genetic variations are possible predictive factors for these adverse events. This retrospective study aimed to investigate if inherited genetic variations in genes encoding drug-metabolizing enzymes and drug transporters localized in the blood-brain barrier are predictive for CNS events. Our results suggest that certain ABCB1, ABCG2 and GSTP1 gene polymorphisms influence CNS toxicity and CNS relapse. A more effective drug-clearance could lead to less toxicity but contribute to a higher chance of relapse and vice versa. Genetic variants in ABCB1, ABCG2 or GSTP1 genes are promising candidates for personalized medicine.

Abstract

Despite improving cure rates in childhood acute lymphoblastic leukemia (ALL), therapeutic side effects and relapse are ongoing challenges. These can also affect the central nervous system (CNS). Our aim was to identify germline gene polymorphisms that influence the risk of CNS events. Sixty single nucleotide polymorphisms (SNPs) in 20 genes were genotyped in a Hungarian non-matched ALL cohort of 36 cases with chemotherapy related acute toxic encephalopathy (ATE) and 544 controls. Five significant SNPs were further analyzed in an extended Austrian-Czech-NOPHO cohort (n = 107 cases, n = 211 controls) but none of the associations could be validated. Overall populations including all nations’ matched cohorts for ATE (n = 426) with seizure subgroup (n = 133) and posterior reversible encephalopathy syndrome (PRES, n = 251) were analyzed, as well. We found that patients with ABCB1 rs1045642, rs1128503 or rs2032582 TT genotypes were more prone to have seizures but those with rs1045642 TT developed PRES less frequently. The same SNPs were also examined in relation to ALL relapse on a case-control matched cohort of 320 patients from all groups. Those with rs1128503 CC or rs2032582 GG genotypes showed higher incidence of CNS relapse. Our results suggest that blood-brain-barrier drug transporter gene-polymorphisms might have an inverse association with seizures and CNS relapse.

Pharmacogenomics of intracellular methotrexate polyglutamates in patients' leukemia cells in vivo

BACKGROUNDInterpatient differences in the accumulation of methotrexate's active polyglutamylated metabolites (MTXPGs) in leukemia cells influence its antileukemic effects.METHODSTo identify genomic and epigenomic and patient variables determining the intracellular accumulation of MTXPGs, we measured intracellular MTXPG levels in acute lymphoblastic leukemia (ALL) cells from 388 newly diagnosed patients after in vivo high-dose methotrexate (HDMTX) (1 g/m2) treatment, defined ALL subtypes, and assessed genomic and epigenomic variants influencing folate pathway genes (mRNA, miRNA, copy number alterations [CNAs], SNPs, single nucleotide variants [SNVs], CpG methylation).RESULTSWe documented greater than 100-fold differences in MTXPG levels, which influenced its antileukemic effects (P = 4 × 10-5). Three ALL subtypes had lower MTXPG levels (T cell ALL [T-ALL] and B cell ALL [B-ALL] with the TCF3-PBX1 or ETV6-RUNX1 fusions), and 2 subtypes had higher MTXPG levels (hyperdiploid and BCR-ABL like). The folate pathway genes SLC19A1, ABCC1, ABCC4, FPGS, and MTHFD1 significantly influenced intracellular MTXPG levels (P = 2.9 × 10-3 to 3.7 × 10-8). A multivariable model including the ALL subtype (P = 1.1 × 10-14), the SLC19A1/(ABCC1 + ABCC4) transporter ratio (P = 3.6 × 10-4), the MTX infusion time (P = 1.5 × 10-3), FPGS mRNA expression (P = 2.1 × 10-3), and MTX systemic clearance (P = 4.4 × 10-2) explained 42% of the variation in MTXPG accumulation (P = 1.1 × 10-38). Model simulations indicated that a longer infusion time (24 h vs. 4 h) was superior in achieving higher intracellular MTXPG levels across all subtypes if ALL.CONCLUSIONSThese findings provide insights into mechanisms underlying interpatient differences in intracellular accumulation of MTXPG in leukemia cells and its antileukemic effectsFUNDINGTHE National Cancer Institute (NCI) and the Institute of General Medical Sciences of the NIH, the Basque Government Programa Posdoctoral de Perfeccionamiento de Personal Investigador doctor, and the American Lebanese Syrian Associated Charities (ALSAC).

Central Nervous System Involvement in Childhood Acute Lymphoblastic Leukemia: An Analysis of Day-One Versus Day-Eight Lumbar Punctures in Remission Induction Therapy

Introduction

Traumatic lumbar puncture (TLP+) can lead to the iatrogenic infiltration of the central nervous system (CNS) by circulating leukemic blast cells in childhood acute lymphoblastic leukemia (ALL). The risk of TLP+ is increased by a number of factors at the time of presentation of the disease, such as a high white cell count (WCC), T-ALL phenotype, and unstable clinical condition of the patient. For this reason, the first lumbar puncture (LP) was deferred until Day Eight of prednisolone prophase during remission induction therapy in one set of patients. The objective was to compare the historical cohort of Day-One LP with Day-Eight LP with respect to the incidence of TLP+ and de novo CNS leukemia.

Methods

A retrospective comparative data analysis of 1,185 childhood ALL patients aged 1-16 years was conducted based on the electronic medical records of the pediatric hematology-oncology department of The Indus Hospital (TIH), Karachi, from January 2010 to August 2018. A total of 600 patients whose LP was done on Day One (January 2010-May 2015) were placed in cohort A, whereas 585 patients whose LP was performed on Day Eight (June 2015-August 2018) were placed in cohort B. After the examination of the cerebrospinal fluid (CSF), the status of CNS infiltration was classified as CNS-1, CNS-2, CNS-3, and TLP+.

Results

A total of 1,185 patients were included in the study, of whom 600 patients were in cohort A and 585 patients in cohort B. The incidence of TLP+ was found to be lower in cohort B (1.7%) as compared with the incidence in cohort A (4.3%) (p-value=0.009). However, there was an increase in the incidence of CNS-3 cases in cohort B (8%) as compared to cohort A (3%) (p-value: <0.001). When the CNS status of both the cohorts was compared with that of the internationally published data, a low incidence of TLP+ cases was noted in patients with LP on Day Eight.

Conclusion

The modified approach of performing the first LP on Day Eight significantly reduced the incidence of TLP+ cases. However, an unusual finding of a significant increase in the CNS-3 leukemia was noted. More prospective studies are needed to investigate this significant increase in CNS-3 cases.

Reduced-dose intensity therapy for pediatric lymphoblastic leukemia: long-term results of the Recife RELLA05 pilot study

Treatment-related mortality is common among children with acute lymphoblastic leukemia (ALL) treated in poor-resource settings. We applied a simplified flow cytometric assay to identify patients with precursor B-cell ALL (B-ALL) at very low risk (VLR) of relapse and treated them with a reduced-intensity treatment plan (RELLA05). VLR criteria include favorable presenting features (age ≥ 1 and < 10 years), white blood cell count of <50 ×109/L, lack of extramedullary leukemia, and minimal residual disease level of <0.01% on remission induction day 19. Except for 2 doses of daunorubicin, treatment of patients with VLR B-ALL consisted of a combination of agents with relatively low myelotoxicity profiles, including corticosteroids, vincristine, L-asparaginase, methotrexate, and 6-mercaptopurine. Cyclophosphamide, systemic cytarabine, and central nervous system radiotherapy were not used. Of 454 patients with ALL treated at the Instituto de Medicina Integral Professor Fernando Figueira in Recife, Brazil, between December 2005 and June 2015, 101 were classified as having VLR B-ALL. There were no cases of death resulting from toxicity or treatment abandonment during remission induction. At a median follow-up of 6.6 years, there were 8 major adverse events: 6 relapses, 1 treatment-related death (from septicemia) during remission, and 1 secondary myeloid leukemia. The estimated 5-year event-free and overall survival rates were 92.0% ± 3.9% and 96.0% ± 2.8%, respectively. The 5-year cumulative risk of relapse was 4.24% ± 2.0%. The treatment was well tolerated. Episodes of neutropenia were of short duration. Patients with B-ALL selected by a combination of presenting features and degree of early response can be successfully treated with a mildly myelosuppressive chemotherapy regimen.

Intrathecal dose intensification by CNS status at diagnosis in the treatment of children with acute lymphoblastic leukemia

OBJECTIVES

Acute lymphoblastic leukemia (ALL) with CNS2 status predicts inferior outcome and a high rate of CNS relapse, similar to overt CNS leukemia (CNS3). The purpose of this study was to determine if intrathecal (IT) dose intensification during induction would improve outcomes and reduce CNS relapse for CNS2 disease.

METHODS

From January 2001 to December 2014, children (1-14 years) with newly diagnosed ALL were treated at the Princess Noorah Oncology Centre (PNOC) following modifications of the Children's Oncology Group (COG) protocols. We intensified IT methotrexate (ITM) during induction for patients with CNS2 disease. Patients were evaluated for overall survival (OS), disease-free survival (DFS), and cumulative incidence of relapse (CIR).

RESULTS

449 children with T-cell (14.3%) or B-cell (85.7%) ALL were treated using PNOC-SR or PNOC-HR regimens (Jan 2001- Dec 2007) or CALL08 regimens (Arm A [SR], Arm B [IR], and Arm C [HR]) (Jan 2008 - Dec 2014). The 5-year OS, DFS, and CIR were 87.2 ± 1.6%, 81.7 ± 1.9%, and 13.0 ± 1.7%, respectively. The OS and DFS of patients with CNS2 were significantly superior to that of patients with CNS3 (P = 0.025 and P = 0.019, respectively). Patients with CNS2 had similar OS and DFS to those with CNS1. None of the patients with CNS2 at initial diagnosis experienced CNS relapse.

CONCLUSIONS

ITM intensification during induction was associated with elimination of CNS recurrence in patients with CNS2 disease and childhood ALL. Controlled studies are needed to confirm this observation.

Neurological Complications of the Leukemias Across the Ages

PURPOSE OF REVIEW

Acute and chronic leukemias are heterogeneous diseases and can affect any part of the body upon initial discovery. Understanding the sequela of systemic involvement is key for proper diagnosis and treatment.

RECENT FINDINGS

Over the decades, new research has emerged regarding neurological complications of the myeloid or lymphoid leukemias. Central nervous system involvement usually confers a poor prognosis and requires emergent treatment. Standard of care still involves systemic therapy, intrathecal administration of chemotherapeutic agents, and cranial radiation. Treatment-related side effects can occur and need to be recognized by any practitioner involved with patient care. It is imperative to understand neurologic complications from leukemia to prevent delays and initiate necessary treatment to maintain neurologic and cognitive function.

Osteonecrosis in children and adolescents with acute lymphoblastic leukemia: a therapeutic challenge

Osteonecrosis (ON) represents one of the most common and debilitating sequelae of antileukemic treatment in children and adolescents with acute lymphoblastic leukemia (ALL). Systematic screening strategies can focus on early detection and intervention to prevent ON from progressing to stages associated with pain and functional impairment. These strategies hold promise for reducing ON-associated morbidity without the risk of impairing leukemia control. Herein, we critically reviewed clinical data on pharmacological, nonpharmacological/nonsurgical, and surgical (including cellular) treatment options for ON, which are covered in the literature and/or are conceivable based on the supposed underlying ON pathophysiology. Prevention of ON progression is of paramount importance, and attempts seem to be more effective in early (precollapse) disease status than in late-stage (collapse) ON. Based on the results of ongoing prospective magnetic resonance imaging screening studies, which will hopefully identify those patients with a high risk of ON progression and debilitating sequelae, prospective interventional studies are urgently needed. Although there is still a lack of high-quality studies, based on currently available data, core decompression surgery combined with cellular therapies (eg, employing mesenchymal stem cells) appears most promising for preventing joint infraction in children at high risk of developing late-stage ON.

Managing CNS disease in adults with acute lymphoblastic leukemia

The central nervous system (CNS) is an important site of involvement by acute lymphoblastic leukemia (ALL) in adults. The prevalence is sufficiently high that prophylactic treatment is routinely given to this sanctuary site in order to eradicate occult disease that might otherwise lead to a relapse. A lumbar puncture should be routinely performed in all newly diagnosed patients with ALL. The risks of CNS leukemia vary by phenotype and genotype. Preventive treatment of the CNS during post-remission therapy has become an integral part of all current ALL treatment protocols. Most treatment regimens combine multiple doses of intrathecal chemotherapy with high-dose systemic methotrexate and/or cytarabine. Cranial irradiation is less commonly used for prophylaxis but is still the most effective treatment for overt CNS leukemia. Recurrences within the CNS usually coincide with or predict soon afterwards for systemic relapse in the marrow and blood.

Neurocognitive Predictors of Academic Outcomes Among Childhood Leukemia Survivors

BACKGROUND

Acute lymphoblastic leukemia is the most common pediatric cancer, and survival approaches 90%. Acute lymphoblastic leukemia survivors are more likely than healthy peers or siblings to experience academic underachievement, yet little is known about neurocognitive predictors of academic outcomes.

OBJECTIVES

Objectives were to compare neurocognitive abilities to age-adjusted standardized norms, examine change over time in neurocognitive abilities, and establish neurocognitive predictors of academic outcomes.

METHODS

Seventy-one children were followed over the course of therapy. Cognitive abilities were assessed during induction when the child was in remission (baseline) and annually for 3 years (years 1, 2, and 3). Reading and mathematics abilities were assessed at year 3.

RESULTS

Fine motor dexterity was significantly below age-adjusted norms at all data points but showed improvement over time. Baseline visual-motor integration was within the reference range but significantly declined by year 3, and mean scores at years 2 and 3 were significantly below age-adjusted norms. Verbal short-term memory was significantly below age-adjusted norms at all assessments. Visual-motor integration predicted reading and mathematics abilities. Verbal short-term memory predicted reading abilities, and visual short-term memory predicted mathematics abilities.

CONCLUSIONS

Central nervous system-directed therapy is associated with specific neurocognitive problems. Visual-spatial skills and verbal and visual short-term memory predict academic outcomes.

IMPLICATIONS FOR PRACTICE

Early assessment of visual-spatial perception and short-term memory can identify children at risk of academic problems. Children who are at risk of academic problems could benefit from a school-based individual educational program and/or educational intervention.

Palmar-plantar erythrodysesthesia syndrome following treatment with high-dose methotrexate or high-dose cytarabine

BACKGROUND

Palmar-plantar erythrodysesthesia syndrome (PPES) is an uncommon side effect of high-dose cytarabine or methotrexate. Prior case reports of PPES have been limited, and the predisposing factors for the development of PPES remain unknown.

METHODS

A review of databases identified 22 patients (1.3%) who developed 39 episodes of PPES among 1720 patients after treatment with high-dose cytarabine or methotrexate.

RESULTS

Symptoms lasted a mean of 6.4 days. Hands and feet were both involved in 68% of the initial episodes. Parenteral opioids were required for pain control by 27% of the patients. In comparison with the 1698 children treated with similar therapy, the children who developed PPES were older (mean age at diagnosis, 14.3 vs 7.7 years; P = 7.5 × 10^-7 ). The frequency of PPES was less common in patients receiving methotrexate alone (7 of 946 or 0.7%) versus cytarabine (7 of 205 or 3.4%; P = .005) but was not different for those receiving both high-dose methotrexate and cytarabine (8 of 569 or 1.4%; P = .32). Prolonged infusions of methotrexate were associated with less frequent PPES in comparison with rapid infusions (P = 1.5 × 10^-5 ), as was the co-administration of dexamethasone with cytarabine (P = 2.5 × 10^-6 ). Self-described race and sex were not associated with PPES. In a multivariate analysis, older age and high-dose cytarabine administration without dexamethasone remained associated with PPES (P = 1.1 × 10^-4 and P = .038, respectively). A genome-wide association study did not identify any associations with PPES meeting the genome-wide significance threshold, but top variants were enriched for skin expression quantitative trait loci, including rs11764092 in AUTS2 (P = 6.45 × 10^-5 ).

CONCLUSIONS

These data provide new insight into the incidence of PPES as well as its risk factors. Cancer 2017;123:3602-8. © 2017 American Cancer Society.

A meta-analysis of the neuropsychological effects of chemotherapy in the treatment of childhood cancer

BACKGROUND

Long-term neuropsychological deficits associated with pediatric cancers and the related treatments have been consistently reported. Whole brain cranial radiation therapy (CRT) is associated with neurocognitive impairment. As a result, physicians are reticent to use CRT in favor of systemic or intrathecal chemotherapy, which have a less clear impact on cognition.

PROCEDURE

The current meta-analysis examined post-treatment neuropsychological performance of children diagnosed with cancer and treated with chemotherapy to better understand the impact of chemotherapy upon cognition. Relevant test scores from 18 empirical studies were utilized and analyzed in comparison to normative data yielding 199 unique effect sizes across nine neurocognitive domains.

RESULTS

Children diagnosed with cancer, who received chemotherapy, demonstrated deficits in attentional capacity (g = -0.277). These deficits are noted in the context of relatively unaffected performance in other domains. When examining potential moderators, those tested more than 5 years after completion of treatment demonstrated better attentional performance than those tested within 5 years of treatment completion.

CONCLUSIONS

These deficits in attentional capacity have implications related to the academic success of these children. Given the potential for remediation strategies within this domain, neuropsychological assessment can be an integral aspect of long-term care plans of survivors of childhood cancer.

Germline genetic variation in ETV6 and risk of childhood acute lymphoblastic leukaemia: a systematic genetic study

BACKGROUND

Hereditary predisposition is rarely suspected for childhood acute lymphoblastic leukaemia (ALL). Recent reports of germline ETV6 variations associated with substantial familial clustering of haematological malignancies indicated that this gene is a potentially important genetic determinant for ALL susceptibility. Our aims in this study were to comprehensively identify ALL predisposition variants in ETV6 and to determine the extent to which they contributed to the overall risk of childhood ALL.

METHODS

Whole-exome sequencing of an index family with several cases of ALL was done to identify causal variants for ALL predisposition. Targeted sequencing of ETV6 was done in children from the Children's Oncology Group and St Jude Children's Research Hospital front-line ALL trials. Patients were included in this study on the basis of their enrolment in these clinical trials and the availability of germline DNA. ETV6 variant genotypes were compared with non-ALL controls to define ALL-related germline risk variants. ETV6 variant function was characterised bioinformatically and correlated with clinical and demographic features in children with ALL.

FINDINGS

We identified a novel non-sense ETV6 variant (p.Arg359X) with a high penetrance in an index family. Subsequent targeted sequencing of ETV6 in 4405 childhood ALL cases identified 31 exonic variants (four non-sense, 21 missense, one splice site, and five frameshift variants) that were potentially related to ALL risk in 35 cases (1%). 15 (48%) of 31 ALL-related ETV6 variants clustered in the erythroblast transformation specific domain and were predicted to be highly deleterious. Children with ALL-related ETV6 variants were significantly older at leukaemia diagnosis than those without (10·2 years [IQR 5·3-13·8] vs 4·7 years [3·0-8·7]; p=0·017). The hyperdiploid leukaemia karyotype was highly over-represented in ALL cases harbouring germline ETV6 risk variants compared with the wild-type group (nine [64%] of 14 cases vs 538 [27%] of 2007 cases; p=0·0050).

INTERPRETATION

Our findings indicated germline ETV6 variations as the basis of a novel genetic syndrome associated with predisposition to childhood ALL. The development of recommendations for clinical interventions and surveillance for individuals harbouring ALL-related ETV6 variants are needed.

FUNDING

US National Institutes of Health and American Lebanese Syrian Associated Charities.

Treatment of young children with CNS-positive acute lymphoblastic leukemia without cranial radiotherapy

BACKGROUND

Due to the long-term sequelae of cranial radiotherapy (CRT), contemporary treatment protocols for children with acute lymphoblastic leukemia (ALL) aim to limit the use of prophylactic CRT. For patients with central nervous system (CNS) involvement with ALL at diagnosis, the use of CRT remains common. Children <5 years of age are a particularly challenging subgroup in whom the consequences of CRT can be devastating.

PROCEDURE

This study retrospectively describes the overall (OS) and event-free survival (EFS) of young children (1-5 years) who were treated for CNS-positive ALL at the Hospital for Sick Children between 2000 and 2013.

RESULTS

Of a total of 19 patients, two were treated with upfront CRT, both as part of the conditioning regimen prior to HSCT. All patients received intensification of CNS-directed chemotherapy by triple intra-thecal chemotherapy (84.2%), use of dexamethasone in induction (57.9%) and maintenance (66.7%), and high-dose methotrexate (77.8%). The OS was 84.2 ± 8.4% and EFS was 79.0 ± 9.4% with a median follow-up time of 4.3 years (range, 2.6-8.2). The cumulative incidence of CNS relapse was 5.2 ± 5.1%.

CONCLUSIONS

We conclude that omission of CRT from the treatment of young children with ALL involving the CNS is associated with acceptable survival and avoids potentially devastating late effects in this group.

Neurocognitive outcomes in long-term survivors of childhood acute lymphoblastic leukemia treated on contemporary treatment protocols: A systematic review

The intensified administration of chemotherapeutic drugs has gradually replaced cranial radiation therapy (CRT) for the treatment of childhood acute lymphoblastic leukemia (ALL). While CRT is often implicated in neurocognitive impairment in ALL survivors, there is a paucity of the literature that evaluates the persistence of neurocognitive deficits in long-term survivors of pediatric ALL who were treated with contemporary chemotherapy-only protocols. Results from this systematic review concurred to the probable cognitive-sparing effect of chemotherapy-based protocols over CRT in long-term survivors. However, coupled with multiple intrinsic and extrinsic factors, survivors who received chemotherapy treatment still suffered from apparent cognitive impairment, particularly in the attention and executive function domains. Notably, there is evidence to suggest that the late neurotoxic effect of methotrexate on survivors' neurocognitive performance may be dose-related. This review also recommends future pharmacokinetic, neuroimaging and genetic studies to illuminate the multifactorial nature of this subject matter and discusses the potential value of neurochemical, physiological, inflammatory and genetic markers for the prediction of susceptibility to neurocognitive impairment in long-term survivors of childhood ALL.

Efficacy of prophylactic additional cranial irradiation and intrathecal chemotherapy for the prevention of CNS relapse after allogeneic hematopoietic SCT for childhood ALL

We evaluated the efficacy of CRT and IT chemotherapy, in addition to conditioning including TBI, for the prevention of CNS relapse, in allogeneic HSCT for childhood ALL. From January 1999 to December 2009, a total of 48 patients, without previous or presenting CNS involvement, underwent HSCT for ALL. All patients received myeloablative conditioning including TBI of 12 or 13.2 Gy and IT chemotherapy twice between days -10 and -2 prior to HSCT. Twenty-five patients received CRT prior to TBI (CRT+), and 23 patients did not (CRT-). CRT+ and CRT- patients had a seven-yr EFS rate of 40.0 ± 9.8% and 41.7 ± 10.6%, respectively (p = 0.8252). The seven-yr relapse rates for CRT+ and CRT- patients were 45.0 ± 11.2% and 38.4 ± 11.6%, respectively (p = 0.7460). CNS relapses were evident in 1 (4.0%) CRT+ patient and 1 (4.4%) CRT- patient (p = 1.000). There were no significant differences in EFS and the probability of CNS relapse between CRT+ and CRT- patients. These results demonstrate that CRT and IT chemotherapy, in addition to conditioning chemotherapy, may not be necessary in childhood ALL patients without previous or presenting CNS involvement.

Triple Intrathecal Therapy Alone With Omission of Cranial Radiation in Children With Acute Lymphoblastic Leukemia

Purpose

To eliminate the toxicities and sequelae of cranial irradiation (CrRT) and to minimize the adverse impact of traumatic lumbar puncture (TLP) with blasts, a prospective study of a modified CNS-directed therapy was conducted in children with acute lymphoblastic leukemia (ALL).

Patients and Methods

Since June 1999, children with newly diagnosed ALL have been treated with triple intrathecal therapy (TIT) alone without CrRT. The first TIT was delayed until the disappearance of blasts from peripheral blood (PB) for up to 10 days of multidrug induction, and CrRT was omitted in all patients. If PB blasts persisted on treatment day 10 (d10), the TIT was then performed.

Results

Of a total of 156 patients, 152 were eligible. Seventeen patients did not have PB blasts at diagnosis. Three fourths of the remaining patients achieved complete clearance of PB blasts by d10. Only hyperleukocytosis at diagnosis showed a significantly lower clearance rate. Six standard-risk patients were upgraded to high risk because of detectable PB blasts on d10. TLPs were encountered in four patients (2.6%), but none were contaminated with lymphoblasts. Neither CNS-2 (less than 5 WBCs/μL with blasts in a nontraumatic sample) nor CNS-3 (≥ 5 WBCs/μL with blasts in a nontraumatic sample or the presence of cranial nerve palsy) was present. The 5-year event-free survival and overall survival rates ± SE were 84.2% ± 3.0% and 90.6% ± 2.4%, respectively. No isolated CNS relapse occurred, but two patients experienced combined CNS relapses. The 7-year cumulative risk of any CNS relapse was 1.4% ± 1.0%.

Conclusion

Delaying first TIT until circulating blasts have cleared may improve CNS control in children with newly diagnosed ALL and preclude the need for CrRT.

A revised definition for cure of childhood acute lymphoblastic leukemia

With improved contemporary therapy, we re-assess long-term outcome in patients completing treatment for childhood acute lymphoblastic leukemia to determine when cure can be declared with a high degree of confidence. In 6 successive clinical trials between 1984 and 2007, 1291(84.5%) patients completed all therapy in continuous complete remission. The post-therapy cumulative risk of relapse or development of a second neoplasm and the event-free survival rate and overall survival were analyzed according to the presenting features and the three treatment periods defined by relative outcome. Over the three treatment periods, there has been progressive increase in the rate of event-free survival (65.2% vs. 74.8% vs. 85.1% [P<0.001]) and overall survival (76.5% vs. 81.1% vs. 91.7% [P<0.001]) at 10 years. The most important predictor of outcome after completion of therapy was the type of treatment. In the most recent treatment period, which omitted the use of prophylactic cranial irradiation, the post-treatment cumulative risk of relapse was 6.4%, death in remission 1.5%, and development of a second neoplasm 2.3% at 10 years, with all relapses except one occurring within 4 years off therapy. None of the 106 patients with the t(9;22)/BCR-ABL1, t(1;19)/TCF3-PBX1 or t(4;11)/MLL-AFF1 had relapsed after 2 years from completion of therapy. These findings demonstrate that with contemporary effective therapy that excludes cranial irradiation, approximately 6% of children with acute lymphoblastic leukemia may relapse after completion of treatment, and those who remain in remission at 4 years post-treatment may be considered cured (i.e., less than 1 % chance of relapse).

Non-Hodgkin’s lymphoma and the CNS: prophylaxis and therapy in immunocompetent and HIV-positive individuals

The involvement of the CNS in individuals with non-Hodgkin's lymphoma is a well-recognised complication. Despite the progress that has been made in controlling cancer at most sites in the body, the outcome of individuals affected by meningeal infiltration is dismal and few patients survive for more than a few months. There are few studies that have addressed the management of CNS disease in AIDS-associated non-Hodgkin's lymphoma, and treatment algorithms have been formulated secondary to protocols in immunocompetent individuals. The prevention and treatment of CNS disease is an important aspect of lymphoma management, and new medications, such as a sustained-release formulation of intrathecal cytarabine, will have an increasingly relevant role.

Morphologic detection of blast cells in the cerebrospinal fluid at diagnosis of adult acute lymphoblastic leukemia appears to be associated with adverse prognosis

INTRODUCTION

Appropriate treatment of central nervous system (CNS) involvement in adult acute lymphoblastic leukemia (ALL) is important for patient prognosis, but the diagnostic criteria of CNS involvement has not been established.

METHODS

The significance of blast cells in the cerebrospinal fluid (CSF) at diagnosis was evaluated in 81 adults newly diagnosed with ALL. Patients with unequivocal morphologic evidence of lymphoblasts in the cytocentrifuged CSF slide were considered to have CNS involvement regardless of the leukocyte count. The outcomes of the patients were analyzed.

RESULTS

Four of the 81 patients (5%) had detectable blast cells, and three of these four patients had less than five leukocytes/μL of CSF. One-year event-free survival (EFS) was 25.0% and 53.2% (P = 0.008) and overall survival (OS) was 50.0% and 68.8% (P = 0.001) in patients with and without CNS involvement, respectively. CNS involvement had prognostic impact on EFS (P = 0.047) and OS (P = 0.009) after adjusting for sex, age, leukocyte count, Philadelphia chromosome status, and immunophenotype.

CONCLUSION

This study suggests that morphologic detection of blast cells in the CSF at diagnosis of adult ALL, regardless of the leukocyte count, is associated with adverse prognosis.

Clinical relevance of the fusion transcripts distribution pattern in mexican children with acute lymphoblastic leukemia

Chromosomal translocation-generated fusion genes in childhood acute lymphoblastic leukemia (ALL) are well-known indicators of prognostic outcome. This study was conducted to establish the clinical relevance of the fusion genes distribution pattern in Mexican children with newly diagnosed ALL. Multiplex RT-PCR assays were used to detect 4 commonest fusion transcripts in 261 Mexican children with B-cell precursor ALL aged 1 to 14 years old, comparing differences in the distribution of the patients between molecular subgroups to a common collection of clinical parameters. We documented a 13% significant proportion of all patients who are more than 10 years of age, harboring fusion transcripts associated with leukocytosis and poor response to remission-induction chemotherapy, than those negative children for chimeric transcripts (P<0.001). Most notable observation was identified a significant number of e2a-pbx1-positive patients who showed a more aggressive disease at diagnosis. As presented here, this report gives an overview of the clinical implications of the fusion gene positivity in Mexican children with ALL in the context of traditional risk stratification variables. Our data support the existence of important ethnic and geographic differences in Mexican population.

Outcome of modified St Jude total therapy 13A for childhood acute lymphoblastic leukemia in the southeast region of Turkey

OBJECTIVE

To fill the gap in the current data on childhood acute lymphoblastic leukemia (ALL) in low-income and middle-income countries.

METHODS

This study included 106 children between the ages of 1 and 17 years with newly diagnosed ALL monitored between 1999 and 2010. All the patients were treated with the modified St Jude Total 13A treatment plan at the Pediatric Hematology Clinic at Harran University.

RESULTS

Sixty-eight (64.2%) patients were boys and 38 (35.8%) were girls. The median age at diagnosis was 5.9 ± 3.7 years. Thirty-eight (35.8%) children were classified as standard risk, 53 (39.3%) were intermediate risk, and 15 (14.2%) were high risk. Thirteen (12.3%) children died in induction before the remission date (43 d of remission induction). Of all the 93 (100%) patients who completed remission induction therapy and whose bone marrow were in remission, 5 (4.7%) had a bone marrow relapse, 1 (0.9%) had a retinal relapse, and 5 (4.7%) had secondary acute myeloid leukemia. At a median follow-up of 44 months (range, 0.36 to 135.5 mo), the estimated 5-year overall survival and event-free survival were 77.4 ± 5% and 68.9 ± 6.5%, respectively. The estimated 5-year overall survival for boys and girls was 76.5 ± 6% and 65.8 ± 8%, respectively (P = 0.182).

CONCLUSIONS

St Jude Total 13A treatment protocols to treat childhood ALL can be successfully adapted, which suggests that such an approach may be useful in low socioeconomic regions; however, it should be noted that secondary leukemia can occur at a high rate.

ETV6-RUNX1-positive childhood acute lymphoblastic leukemia: improved outcome with contemporary therapy

ETV6-RUNX1 fusion is the most common genetic aberration in childhood acute lymphoblastic leukemia (ALL). To evaluate whether outcomes for this drug-sensitive leukemia are improved by contemporary risk-directed therapy, we studied clinical features, response and adverse events of 168 children with newly diagnosed ETV6-RUNX1-positive ALL on St Jude Total Therapy studies XIIIA (N=36), XIIIB (N=38) and XV (N=94). Results were compared with 494 ETV6-RUNX1-negative B-precursor ALL patients. ETV6-RUNX1 was associated with age 1-9 years, pre-treatment classification as low risk and lower levels of minimal residual disease (MRD) on day 19 of therapy (P<0.001). Event-free survival (EFS) or overall survival (OS) did not differ between patients with or without ETV6-RUNX1 in Total XIIIA or XIIIB. By contrast, in Total XV, patients with ETV6-RUNX1 had significantly better EFS (P=0.04; 5-year estimate, 96.8±2.4% versus 88.3±2.5%) and OS (P=0.04; 98.9±1.4% versus 93.7±1.8%) than those without ETV6-RUNX1. Within the ETV6-RUNX1 group, the only significant prognostic factor associated with higher OS was the treatment protocol Total XV (versus XIIIA or XIIIB) (P=0.01). Thus, the MRD-guided treatment schema including intensive asparaginase and high-dose methotrexate in the Total XV study produced significantly better outcomes than previous regimens and demonstrated that nearly all children with ETV6-RUNX1 ALL can be cured.

The utility of performing the initial lumbar puncture on day 8 in remission induction therapy for childhood acute lymphoblastic leukemia: TCCSG L99-15 study

BACKGROUND

Traumatic lumbar puncture with leukemic blasts (TLP+), which has been reported to occur 5-10%, in the previous studies, adversely affects the outcome of children with acute lymphoblastic leukemia (ALL). Based on the results from our previous study, we deferred the initial lumbar puncture until day 8 in remission induction therapy in order to reduce the frequency of cases with TLP+.

PROCEDURE

The study was conducted as a prospective cohort study within the Tokyo Children's Cancer Study Group (TCCSG) L99-15 study. Between April 1999 and June 2003, 754 children with newly diagnosed ALL enrolled. The patients received the initial intrathecal chemotherapy after 7 days of prednisolone treatment. The incidence of central nervous system (CNS)-positive (the presence of leukemic blasts in cerebrospinal fluid or cranial nerve palsy) including TLP+ cases and cumulative incidence of CNS relapse were examined.

RESULTS

The incidence of CNS-positive and TLP+ was 2.9% (n = 22) and 0.8% (n = 6), respectively. These incidences were much lower than those in the representative study groups employing the initial IT on day 1. Of 22 patients with CNS-positive, only one patient relapsed in CNS, whereas 22 of the remaining CNS-negative 723 patients suffered from CNS relapse. Overall, event-free survival at 4 year was 78.2 ± 1.6%. Four-year cumulative incidence of any CNS relapse was 3.3 ± 0.7%, which improved from our previous study in spite of limiting the use of cranial irradiation.

CONCLUSIONS

Our strategy reduced the frequency of CNS-positive patients who required reinforcement of CNS-directed therapy without compromising overall outcome.

Escalating intravenous methotrexate improves event-free survival in children with standard-risk acute lymphoblastic leukemia: a report from the Children's Oncology Group

Children's Cancer Group-1991 selected 2 components from the Children's Cancer Group studies shown to be effective in high-risk acute lymphoblastic leukemia and examined them in children with National Cancer Institute standard-risk acute B-precursor lymphoblastic leukemia. These were (1) vincristine and escalating IV methotrexate (MTX) without leucovorin rescue during the interim maintenance (IM) phases and (2) addition of a second delayed intensification (DI) phase. Eligible patients (n = 2078) were randomly assigned to regimens containing either oral (PO) MTX, PO mercaptopurine, dexamethasone, and vincristine or IV MTX during IM phases, and regimens with either single DI or double DI. Five-year event-free survival (EFS) and overall survival for patients on the PO MTX arms were 88.7% ± 1.4% and 96% ± 0.9% versus 92.6% ± 1.2% and 96.5% ± 0.8% for those on the IV MTX arms (P = .009, P = .66). Five-year EFS and overall survival for patients who received single DI were 90.9% ± 1.3% and 97.1% ± 0.8% versus 90.5% ± 1.3% and 95.4% ± 3.8% for those who received double DI (P = .71, P = .12). No advantage was found for a second DI; however, replacement of PO MTX, PO mercaptopurine, vincristine, and dexamethasone during IM with vincristine and escalating IV MTX improved EFS.

Nutritional intake of long-term survivors of childhood acute lymphoblastic leukemia: evidence for bone health interventional opportunities

BACKGROUND

Survivors of childhood acute lymphoblastic leukemia (ALL) are vulnerable to exaggeration of the aging process including decreased bone mineral density (BMD). As little is known about their dietary or nutrient intake that may affect their long-term bone health, we examined nutrient intake in long-term survivors of childhood ALL.

PROCEDURE

Survivors (n = 164) of childhood ALL who had completed treatment for at least 5 years and were in continuous remission, completed a 110-item food questionnaire that reflected dietary intake over the previous year. The analyzed cohort comprised 34 females and 38 males younger than 19 years and 45 females and 47 males at least 19 years. Reported nutrient intake and food selection were compared with age-specific Recommended Dietary Allowance and USDA Pyramid Food Guide. Body mass index was compared to the general US population, adjusted for age, gender, Tanner stage and race.

RESULTS

Less than 30% of participants met recommended dietary intakes for vitamin D, calcium, potassium, or magnesium regardless of age. Mean daily caloric intake was 2,204 kcal (51% from carbohydrates) for younger and 2,160 kcal (49% from carbohydrates) for older participants. Energy intake from sweets was 70% higher than recommended. Participants < 19 years were less likely to have a healthy weight (odds ratio 0.48, 95% CI 0.30-0.79); > 19 years more likely to be overweight (odds ratio 1.95, 95% CI 1.11-3.32, P < 0.002).

CONCLUSIONS

Survivors of childhood ALL need careful dietary intervention to optimize long-term health.

Prognostic significance of the initial cerebro-spinal fluid (CSF) involvement of children with acute lymphoblastic leukaemia (ALL) treated without cranial irradiation: results of European Organization for Research and Treatment of Cancer (EORTC) Children Leukemia Group study 58881

AIM OF THE STUDY

To evaluate the prognostic significance of the initial cerebro-spinal fluid (CSF) involvement of children with ALL enrolled from 1989 to 1996 in the EORTC 58881 trial.

PATIENTS AND METHODS

Patients (2025) were categorised according to initial central nervous system (CNS) status: CNS-1 (CNS negative, n=1866), CNS-2 (<5 leucocytes/mm(3), CSF with blasts, n=50), CNS-3 (CNS positive, n=49), TLP+ (TLP with blasts, n=60). CNS-directed therapy consisted in intravenous (i.v.) methotrexate (5 g/sqm) in 4-10 courses, and intrathecal methotrexate injections (10-20), according to CNS status. Cranial irradiation was omitted in all patients.

RESULTS

In the CNS1, TLP+, CNS2 and CNS3 group the 8-year EFS rate (SE%) was 69.7% (1.1%), 68.8% (6.2%), 71.3% (6.5%) and 68.3% (6.2%), respectively. The 8-year incidence of isolated CNS relapse (SE%) was 3.4% (0.4%), 1.7% (1.7%), 6.1% (3.5%) and 9.4% (4.5%), respectively, whereas the 8-year isolated or combined CNS relapse incidence was 7.6% (0.6%), 3.5% (2.4%), 10.2% (4.4%) and 11.7% (5.0%), respectively. Patients with CSF blasts had a higher rate of initial bad risk features. Multivariate analysis indicated that presence of blasts in the CSF had no prognostic value: (i) for EFS and OS; (ii) for isolated and isolated or combined CNS relapse; WBC count<25 × 10(9)/L and Medac E-coli asparaginase treatment were each related to a lower CNS relapse risk.

CONCLUSIONS

The presence of initial CNS involvement has no prognostic significance in EORTC 58881. Intensification of CNS-directed chemotherapy, without CNS radiation, is an effective treatment of initial meningeal leukaemic involvement.

Glucocorticoid use in acute lymphoblastic leukaemia

Glucocorticoids (prednisone and dexamethasone) play an essential part in the treatment of acute lymphoblastic leukaemia (ALL), but their optimum doses and bioequivalence have not been established. Results of preclinical studies have shown that dexamethasone has a longer half-life and better CNS penetration than does prednisone. In prospective randomised trials, dexamethasone improved control of CNS leukaemia. At a prednisone-to-dexamethasone dose ratio of less than seven, dexamethasone (6-18 mg/m(2) per day) resulted in a better event-free survival than did prednisone (40-120 mg/m(2) per day), and high-dose dexamethasone (10-18 mg/m(2) per day) improved the outcome of T-cell ALL and high-risk ALL. However, dexamethasone caused more adverse effects, including infection, bone fracture, osteonecrosis, mood and behaviour problems, and myopathy. At a dose ratio greater than seven, the two drugs showed no difference in efficacy. Therefore, the efficacy of prednisone and dexamethasone is dose dependent and needs to be carefully assessed against the toxic effects. Moreover, although dexamethasone generally showed increased activity in ALL cells in vitro, the dose ratio of the two drugs that exerted equivalent cytotoxic effects differed substantially in samples from individuals. The selection of the type and dose of glucocorticoid should be based on the risk of relapse, treatment phase, and the chemotherapeutic drugs used concomitantly.

Overt testicular disease at diagnosis in childhood acute lymphoblastic leukemia: prognostic significance and role of testicular irradiation

OBJECTIVE

To analyze the prognostic impact of overt testicular disease (OTD) at diagnosis and role of testicular irradiation in the same.

METHODS

Data of 579 boys treated at our center over 16 years was reviewed.

RESULTS

Fourteen (2.4%) males had OTD. 10 (71.4%) of these had high-risk disease. Patients with OTD, had a significantly higher incidence of mediastinal-adenopathy (p=0.001), hyperleucocytosis (p=0.004) and CNS disease at presentation (p<0.0001) compared to patients in continuous complete remission (CCR). 4 of the 11 patients with OTD, who opted for therapy, had relapse; 2 are in CCR. Although, survival in patients with OTD was inferior (p=0.183) compared to patients without OTD, it was not an independent prognostic factor (p=0.47). In the entire study cohort, symptom-diagnosis interval (p=0.006), white cell (p=0.001) and platelet count (p=0.001) at presentation were significantly associated with survival (Cox multivariate regression analysis).

CONCLUSIONS

OTD was not an independent prognostic factor, despite association with high-risk features. Survival outcome was inferior. The observations indicate the need of revaluation of the present protocol with incorporation of intermediate dose and subsequently high-dose methotrexate (after assessment for toxicity and tolerance), risk-stratified therapy and plausibly omission of testicular irradiation.

Pattern of relapse in childhood ALL: challenges and lessons from a uniform treatment protocol

This retrospective analysis of 254 children less than 15 years of age treated with MCP-841 protocol from June 1992 to June 2002 was undertaken to identify the pattern of relapse and determine management lacunae. Two hundred twenty-three (87.8%) children achieved a complete remission of whom 40 (17.9%) relapsed. The mean age of relapsed patients was 6.5 years. The male/female ratio was 9:1. There were 23 (57.5%) isolated bone marrow (BM), 7 (17.5%) isolated central nervous system (CNS), 2 (5%) isolated testicular, 5 (12.5%) BM+testes and 1 each of BM+CNS, CNS+testes, and isolated bone relapses. Twenty-seven children (67.5%) relapsed on-therapy whereas 13 (32.5%) relapsed posttherapy. All 9 CNS relapses occurred on-therapy whereas 5/8 (62.5%) of testicular relapses occurred posttherapy. Lymphadenopathy was the only significant predictor for relapse. High-risk features such as age less than 1 year and greater than 10 years (P=0.047) and white cell count greater than 50.0 x 10(9)/L (P=0.044) were significantly more frequent in patients with early on-therapy relapse than in patients with off-therapy relapse. The overall survival in the entire study cohort was 67+/-3.5%. Modest survival outcome, relapse while on chemotherapy and the higher incidence of CNS and testicular relapse indicate the need for reappraisal of our treatment protocol. There is a need of identifying risk factors and high-risk groups in our set of patients and risk-stratified intensification of chemotherapy in them.

Central nervous system prophylaxis in adults with acute lymphoblastic leukemia: current and emerging therapies

Central nervous system (CNS) recurrence continues to be a significant complication in the treatment of adult patients with acute lymphoblastic leukemia (ALL). Preventing CNS recurrence has been a therapeutic challenge and has not been addressed critically in many clinical trials. Adult studies modeled on childhood ALL studies have used multiple treatment modalities, including radiation therapy, systemic therapy, intrathecal therapy, and combinations thereof. Cranial irradiation is effective but is offset by substantial toxicity, including neurologic sequelae. Systemic chemotherapy, especially with cytarabine (AraC) and methotrexate, has demonstrated promise in decreasing CNS recurrence, but therapeutic levels of drugs in the cerebrospinal fluid (CSF) are not maintained. Intrathecal chemotherapy with or without high-dose systemic therapy is the most common approach to CNS prophylaxis. Liposomal AraC recently has become available and confers prolonged levels of free AraC in the CSF, a critical requirement for CNS prophylactic therapy. This review discusses the various modalities used for CNS prophylaxis in patients with ALL and the emerging trends, with specific emphasis on the outcome in terms of event-free survival and toxicity.

Long-term results of St Jude Total Therapy Studies 11, 12, 13A, 13B, and 14 for childhood acute lymphoblastic leukemia

We analyzed the long-term outcome of 1011 patients treated in five successive clinical trials (Total Therapy Studies 11, 12, 13A, 13B, and 14) between 1984 and 1999. The event-free survival improved significantly (P=0.003) from the first two trials conducted in the 1980s to the three more recent trials conducted in the 1990s. Approximately 75% of patients treated in the 1980s and 80% in the 1990s were cured. Early intensive triple intrathecal therapy, together with more effective systemic therapy, including consolidation and reinduction treatment (Studies 13A and 13B) as well as dexamethasone (Study 13B), resulted in a very low rate of isolated central nervous system (CNS) relapse rate (<2%), despite the reduced use of cranial irradiation. Factors consistently associated with treatment outcome were age, leukocyte count, immunophenotype, DNA index, and minimal residual disease level after remission induction treatment. Owing to concerns about therapy-related secondary myeloid leukemia and brain tumors, in our current trials we reserve the use of etoposide for patients with refractory or relapsed leukemia undergoing hematopoietic stem cell transplantation, and cranial irradiation for those with CNS relapse. The next main challenge is to further increase cure rates while improving quality of life for all patients.

Effect of allopurinol versus urate oxidase on methotrexate pharmacokinetics in children with newly diagnosed acute lymphoblastic leukemia

BACKGROUND

Allopurinol and urate oxidase are both effective in preventing or treating hyperuricemia during remission induction therapy for lymphoid malignancies, but to the authors' knowledge, their effects on concomitant anticancer drug therapy have not been compared.

METHODS

The authors compared plasma methotrexate pharmacokinetics in pediatric patients with newly diagnosed acute lymphoblastic leukemia who received concomitant allopurinol (n = 20) versus those treated with nonrecombinant or recombinant urate oxidase (n = 96) during high-dose methotrexate administration before conventional remission induction therapy.

RESULTS

The minimum plasma concentration of uric acid was significantly (P < .0001) lower after urate oxidase treatment than the concentration after allopurinol treatment. Methotrexate clearance was significantly higher (median, 117.1 mL/minute/m(2) vs 91.1 mL/minute/m(2); P = .019) in patients who received urate oxidase. A higher proportion of patients in the allopurinol group had elevated methotrexate plasma concentrations (36% vs 7%; P = .003) and experienced mucositis (45% vs 16%; P = .003) after methotrexate treatment compared with the urate oxidase group.

CONCLUSIONS

The lower rate of methotrexate clearance in patients who received allopurinol likely reflected a less potent hypouricemic effect of allopurinol, leading to precipitation of uric acid in renal tubules. Hence, during remission induction therapy for lymphoid malignancies, the authors concluded that renally excreted drugs should be monitored closely, especially in patients who are receiving allopurinol.

Long-term results of Taiwan Pediatric Oncology Group studies 1997 and 2002 for childhood acute lymphoblastic leukemia

The long-term outcome of 1390 children with acute lymphoblastic leukemia (ALL), treated in two successive clinical trials (Taiwan Pediatric Oncology Group (TPOG)-ALL-97 and TPOG-ALL-2002) between 1997 and 2007, is reported. The event-free survival improved significantly (P=0.0004) over this period, 69.3+/-1.9% in 1997-2001 to 77.4+/-1.7% in 2002-2007. A randomized trial in TPOG-97 testing L-asparaginase versus epidoxorubicin in combination with vincristine and prednisolone for remission induction in standard-risk (SR; low-risk) patients yielded similar outcomes. Another randomized trial, in TPOG-2002, showed that for SR patients, two reinduction courses did not improve long-term outcome over one course. Decreasing use of prophylactic cranial irradiation in the period 1997-2008 was not associated with increased rates of CNS relapse, prompting complete omission of prophylactic cranial irradiation from TPOG protocols, beginning in 2009. Decreased use of etoposide and cranial irradiation likely contributed to the low incidence of second cancers. High-risk B-lineage ALL, T-cell, CD10 negativity, t(9;22), infant, and higher leukocyte count were consistently adverse factors, whereas hyperdiploidy >50 was a consistently favorable factor. Higher leukocyte count and t(9;22) retained prognostic significance in both TPOG-97 and TPOG-2002 by multivariate analysis. Although long-term outcome in TPOG clinical trials is comparable with results being reported worldwide, the persistent strength of certain prognostic variables and the lower frequencies of favorable outcome predictors, such as ETV6-RUNX1 and hyperdiploidy >50, in Taiwanese children warrant renewed effort to cure a higher proportion of patients while preserving their quality of life.

Increased vulnerability of the spinal cord to radiation or intrathecal chemotherapy during adolescence: A report from the Children's Oncology Group

PURPOSE

To assess the rate of spinal cord toxicity in adolescents resulting from chemoradiotherapy of parameningeal sarcoma.

METHODS AND MATERIALS

Of 152 patients with parameningeal sarcoma treated per the Intergroup Rhabdomyosarcoma Study Group protocol from 1977 through 1989, eight developed paralyzing ascending myelitis after intrathecal chemotherapy with cytosine arabinoside, methotrexate, and hydrocortisone administered during and after radiation therapy to volumes that included part of the spinal cord. The eight cases include three not previously published.

RESULTS

Of eight patients who developed CNS toxicity after intrathecal chemotherapy and radiotherapy for parameningeal rhabdomyosarcoma, all but one were between 13 and 18 years of age when treated. This severe toxicity occurred in one quarter of 28 adolescents treated with the regimen in comparison with one of 123 children 12 years of age or less (P < 0.0001), a rate that was as much as 30 times higher in the adolescents. Lengthening of the spinal cord during the pubertal growth spurt may account for the apparent increased vulnerability.

CONCLUSIONS

Chemoradiotoxicity-associated spinal cord injury appears to be more likely to occur in adolescents than in younger or older ages. This observation appears to reverse a conventional wisdom in which the central nervous system is thought to become more resistant to the neurotoxic effects of chemoradiotherapy as it matures.

Treating childhood acute lymphoblastic leukemia without cranial irradiation

BACKGROUND

Prophylactic cranial irradiation has been a standard treatment in children with acute lymphoblastic leukemia (ALL) who are at high risk for central nervous system (CNS) relapse.

METHODS

We conducted a clinical trial to test whether prophylactic cranial irradiation could be omitted from treatment in all children with newly diagnosed ALL. A total of 498 patients who could be evaluated were enrolled. Treatment intensity was based on presenting features and the level of minimal residual disease after remission-induction treatment. The duration of continuous complete remission in the 71 patients who previously would have received prophylactic cranial irradiation was compared with that of 56 historical controls who received it.

RESULTS

The 5-year event-free and overall survival probabilities for all 498 patients were 85.6% (95% confidence interval [CI], 79.9 to 91.3) and 93.5% (95% CI, 89.8 to 97.2), respectively. The 5-year cumulative risk of isolated CNS relapse was 2.7% (95% CI, 1.1 to 4.3), and that of any CNS relapse (including isolated relapse and combined relapse) was 3.9% (95% CI, 1.9 to 5.9). The 71 patients had significantly longer continuous complete remission than the 56 historical controls (P=0.04). All 11 patients with isolated CNS relapse remained in second remission for 0.4 to 5.5 years. CNS leukemia (CNS-3 status) or a traumatic lumbar puncture with blast cells at diagnosis and a high level of minimal residual disease (> or = 1%) after 6 weeks of remission induction were significantly associated with poorer event-free survival. Risk factors for CNS relapse included the genetic abnormality t(1;19)(TCF3-PBX1), any CNS involvement at diagnosis, and T-cell immunophenotype. Common adverse effects included allergic reactions to asparaginase, osteonecrosis, thrombosis, and disseminated fungal infection.

CONCLUSIONS

With effective risk-adjusted chemotherapy, prophylactic cranial irradiation can be safely omitted from the treatment of childhood ALL. (ClinicalTrials.gov number, NCT00137111.)

Effects of chemotherapy on neurocognitive function in children with acute lymphoblastic leukemia: a critical review of the literature

Chemotherapy-only treatment has increasingly become the standard of treatment for childhood acute lymphoblastic leukemia (ALL). The objective of this review is to assess the present state of knowledge of the neurocognitive effects of central nervous system (CNS)-directed chemotherapy in children with ALL, and to formulate directions for future research. We performed a review of studies published since 1997, that included an ALL group treated with chemotherapy only and a control group. Twenty-one studies met our inclusion criteria. There is evidence of subtle long-term neurocognitive deficits survivors of childhood ALL after treatment with chemotherapy only. These involve mainly processes of attention and of executive functioning, while global intellectual function is relatively preserved. Young age at diagnosis and female sex emerged as risk factors.

Increased risk for CNS relapse in pre-B cell leukemia with the t(1;19)/TCF3-PBX1

To evaluate the impact of contemporary therapy on the clinical outcome of children with pre-B acute lymphoblastic leukemia (ALL) and the t(1;19)/TCF3/PBX1, we analyzed 735 patients with B-cell precursor ALL treated in four successive protocols at St Jude Children's Research Hospital. The 41 patients with the t(1;19) had a comparable event-free survival to that of the 694 patients with other B-cell precursor ALL (P=0.63; 84.2+/-7.1% (s.e.) vs 84.0+/-1.8% at 5 years). However, patients with the t(1;19) had a lower cumulative incidence of any hematological relapse (P=0.06; 0 vs 8.3+/-1.2% at 5 years) but a significantly higher incidence of central nervous system (CNS) relapse (P<0.001; 9.0+/-5.1% vs 1.0+/-0.4% at 5 years). In a multivariate analysis, the t(1;19) was an independent risk factor for isolated CNS relapse. These data suggest that with contemporary treatment, patients with the t(1;19) and TCF3/PBX1 fusion have a favorable overall outcome but increased risk of CNS relapse.

Propofol-fentanyl versus propofol alone for lumbar puncture sedation in children with acute hematologic malignancies: propofol dosing and adverse events

OBJECTIVE

We sought to determine whether the combination of propofol and fentanyl results in lower propofol doses and fewer adverse cardiopulmonary events than propofol and placebo for lumbar puncture in children with acute hematologic malignancies.

DESIGN

Randomized, controlled, double blind, crossover study.

SETTING

Pediatric Sedation Program.

PATIENTS

Children with acute leukemia or lymphoma receiving sedation for lumbar puncture.

INTERVENTIONS

Each patient received two sedations in random order, one with propofol/placebo and one with propofol/fentanyl. The study investigator and patient/parent were blinded to placebo or fentanyl. Data collected included patient age and diagnosis, propofol dose and adverse events. Adverse events included oxygen saturation <94%, airway obstruction, apnea, hypotension, and bradycardia (<5% mean for age). Logistic regression analysis was used to assess probability of adverse events and the Wilcoxon Signed Rank and McNemar's tests were used for paired comparisons.

MEASUREMENTS AND MAIN RESULTS

Twenty-two patients were enrolled. Fourteen patients were male and eight were female. Each patient was studied twice for a total of 44 sedations. The median age was 5.0 yrs (range, 2.2-17.2 yrs). All procedures were successfully completed. The median total dose of propofol was 5.05 mg/kg (range, 2.4-10.2 mg/kg) for propofol/placebo vs. 3.00 mg/kg (range 1.4-10.5 mg/kg) for propofol/fentanyl (p < 0.001). Twelve adverse events occurred in 11 of 22 patients (50.0%) propofol/placebo compared with 6 of 22 (18.2%) propofol/fentanyl (p = 0.02). The most common adverse event was hypotension.

CONCLUSIONS

The combination of propofol and fentanyl vs. propofol alone for lumbar puncture sedation in children with acute hematologic malignancies resulted in lower propofol doses and fewer adverse events.

Clinical consequences of hyperglycemia during remission induction therapy for pediatric acute lymphoblastic leukemia

Hyperglycemia adversely affects outcome in adult patients with acute lymphoblastic leukemia (ALL), but its impact on children with this disease is unknown. We evaluated the relationship between hyperglycemia during remission induction therapy and clinical outcomes among pediatric patients with ALL. We reviewed the records of patients enrolled on four consecutive ALL protocols (Total Therapy protocols XIIIA, XIIIB, XIV and XV) at St Jude Children's Research Hospital from 1991 to 2007 and identified those who experienced hyperglycemia (glucose >or=200 mg per 100 ml) during remission induction. Complete remission (CR) rates at the end of induction, event-free survival (EFS), overall survival (OS), cumulative incidence of relapse and occurrence of infections were compared between those who did and did not experience hyperglycemia. Of 871 patients analyzed, 141 (16%) experienced hyperglycemia during remission induction. Patients with hyperglycemia were significantly older than the other patients (P<0.0001). There was no significant difference in CR rate (P=0.92), EFS (P=0.80), OS (P=0.28), cumulative incidence of relapse (P=0.59) or in the probability or types of infection between patients who did and did not experience hyperglycemia. Pediatric patients with or without hyperglycemia during remission induction for ALL have similar clinical outcome. Occurrence of hyperglycemia does not warrant alteration of the antileukemic regimen.

Practice of central nervous system prophylaxis and treatment in acute leukemias in Spain. Prospective registry study

BACKGROUND AND OBJECTIVE

Central nervous system (CNS) involvement in patients diagnosed with acute leukemias (AL) is an uncommon complication with poor prognosis. The indication and the schedules of prophylaxis and treatment of CNS involvement in AL are not homogenous among countries and within the same country. The aim of this prospective longitudinal study was to analyze and report the practice of CNS prophylaxis and treatment in patients with AL in Spain.

PATIENTS AND METHOD

Prospective study conducted from June 2005 to June 2006. Adult patients (> or = 18 yr.) diagnosed with AL who received CNS prophylaxis or treatment were consecutively included through online registration.

RESULTS

265 patients from 32 hospitals were included. Mean (standard deviation) age was 44 (16) yr. and 133 (50%) were males. For acute lymphoblastic leukemia patients (n = 158), CNS therapy was given to 12 cases (10 at diagnosis and 2 at relapse) and consisted of triple intrathecal therapy (TIT, methotrexate, cytarabine and hydrocortisone) in 11 and liposomal depot cytarabine in one. CNS prophylaxis (n = 146) consisted of TIT in 135 cases, intrathecal methotrexate in 7, intrathecal cytarabine in 2 and intrathecal liposomal depot cytarabine in 2. No cranial irradiation either for prophylaxis or therapy was given in any case. In acute myeloblastic leukemia patients (n = 107), CNS therapy was administered to 17 cases (9 at diagnosis and 8 at relapse). Intrathecal therapy consisted of TIT in 11, intrathecal liposomal depot cytarabine in 5 and intrathecal cytarabine in one. One patient also received craniospinal irradiation. CNS prophylaxis (n = 90) consisted of TIT in 68 cases and intrathecal methotrexate in 22.

CONCLUSIONS

In Spain, the patterns of CNS prophylaxis and therapy for AL are homogeneous. TIT was the most frequent schedule for CNS prophylaxis and therapy. The lack of use of cranial or craniospinal irradiation and the administration of new drugs (i.e.: liposomal depot cytarabine) for CNS therapy and prophylaxis is of note.

Measurement of cerebrospinal fluid protein is unnecessary in children with leukemia

To determine the incidence and importance of abnormal cerebrospinal fluid (CSF) protein in children with acute leukemia, we performed a retrospective chart review. On 160 pediatric patients a total of 2,172 LPs were performed (median per patient = 15; range 1-38). Overall, 314 (14%) of CSF protein measurements were abnormal: 141 (7%) were abnormally low (<15 mg/dL) and 158 (7%) were abnormally high (>45 mg/dL). In no case did an abnormal CSF protein impact patient management. We conclude that routine measurement of CSF protein is not indicated in children with acute leukemia.