Impact of Intrathecal Triple Therapy Versus Intrathecal Methotrexate on Disease-Free Survival for High-Risk B-Lymphoblastic Leukemia: Children's Oncology Group Study AALL1131

Heterogeneity of IKZF1 genomic alterations and risk of relapse in childhood B-cell precursor acute lymphoblastic leukemia

Genomic alterations of IKZF1 are common and associated with adverse clinical features in B-progenitor acute lymphoblastic leukemia (B-ALL). The relationship between the type of IKZF1 alteration, B-ALL genomic subtype and outcome are incompletely understood. B-ALL subtype and genomic alterations were determined using transcriptome and genomic sequencing, and SNP microarray analysis in 688 pediatric patients with B-ALL in the St. Jude Total Therapy XV and 16 studies. IKZF1 alterations were identified in 115 (16.7%) patients, most commonly in BCR::ABL1 (78%) and CRLF2-rearranged, BCR::ABL1-like B-ALL (70%). These alterations were associated with 5-year cumulative incidence of relapse (CIR) of 14.8 ± 3.3% compared to 5.0 ± 0.9% for patients without any IKZF1 alteration (P < 0.0001). In separate multivariable analyses adjusting for genetic subtype groups and other factors, IKZF1 deletions of exons 4-7 (P = 0.0002), genomic IKZF1plus with any IKZF1 deletion (P = 0.006) or with focal IKZF1 deletion (P = 0.0007), and unfavorable genomic subtypes (P < 0.005) were independently adverse prognostic factors. Associations of genomic IKZF1plus and exon 4-7 deletions with adverse outcomes were confirmed in an independent cohort. The type of IKZF1 alteration, together with the subtype, are informative for risk stratification and to predict response in patients with B-ALL.

Hepatic sinusoidal congestion associated with inotuzumab therapy in patients with B-cell acute lymphoblastic leukemia, a proposal for a new clinical entity: Calicheamicin syndrome

Inotuzumab (InO) is an anti-CD22 immunoconjugate for patients with relapsed or refractory CD22 positive B-cell acute lymphoblastic leukemia (B-ALL). Liver toxicity is a recognized side effect of InO, including sinusoidal obstruction syndrome (SOS), but is not fully understood. This study describes a new aspect of InO-induced hepatotoxicity by outlining six patients who developed abnormal liver function tests (LFTs) and thrombocytopenia, with liver biopsies showing sinusoidal congestion without evidence of SOS. Liver biopsies were obtained from all six patients and LFTs were monitored before initiating InO treatment, during treatment, and after discontinuing treatment. All six patients experienced abnormal LFTs at a median of 15 days after the last dose of InO and improvement in LFTs at a median of 17 days after discontinuing InO. Initial baseline AST, ALT, ALP, and total bilirubin values prior to InO therapy ranged from 10-45 U/L, 10-45 U/L, 60-207 U/L, and 0.2-0.9 mg/dL respectively and increased up to 2 to 4 times the upper limit of normal after completing varying cycles of InO with hepatotoxicity grades ranging from 1-2. LFTs returned to 1 to 1.5 times the upper limit of normal after discontinuing InO. The patients' liver biopsies all demonstrated different levels of hepatic sinusoidal congestion (HSC) without evidence of SOS. This study provides new evidence describing HSC, where we hypothesize that InO induced hepatotoxicity are due to calicheamicin. We propose a new clinical entity called "calicheamicin syndrome" with its quadriad components: History of using InO or GO, elevated LFTs, thrombocytopenia, and abnormal liver imaging.

Intrainfusion Drug Monitoring and Algorithm-Based Dose Adjustments for Children With ALL Receiving High-Dose Methotrexate Are Feasible and Safe in Costa Rica, a Low- and Middle-Income Country

PURPOSE

Infusions of high-dose methotrexate at 5 g/m2 over 24 (HDMTX) as a single infusion for pediatric patients with high-risk precursor B-cell ALL are known to lead to superior outcomes. The Hospital Nacional de Niños Dr Carlos Sáenz Herrera, part of the public system Caja Costarricense de Seguro Social in Costa Rica (HNN), has been historically unable to provide this therapy secondary to the required intensive monitoring and cost-prohibitive toxicity support.

METHODS

We report our experience providing HDMTX at HNN, to our knowledge, for the first time using an algorithm-based individualized HDMTX protocol designed to prevent toxic levels of methotrexate. The protocol checks intrainfusion methotrexate levels at hours 2 and 6 or 8, with adjustments in the infusion downward if levels predict a high/toxic end infusion concentration.

RESULTS

Fifty-two patients (who received 196 total evaluable infusions between 2017 and 2019) were included. Rate adjustments were required during 51 infusions (24.6%). Significant methotrexate-related toxicities were rare and included acute kidney injury (≥grade 3, 0.5%, n = 1), neurotoxicity (≥grade 3, 1%, n = 2), mucositis (≥grade 3, 4.8%, n = 10), and neutropenia (≥grade 3, 24.6%, n = 51). No ≥grade 4 toxicities occurred.

CONCLUSION

A real-time, algorithm-based individualized HDMTX infusion is a practical and safe way to administer HDMTX in a low- and middle-income country.

Blinatumomab in Standard-Risk B-Cell Acute Lymphoblastic Leukemia in Children

BACKGROUND

B-cell acute lymphoblastic leukemia (B-cell ALL) is the most common childhood cancer. Despite a high overall cure rate, relapsed B-cell ALL remains a leading cause of cancer-related death among children. The addition of the bispecific T-cell engager molecule blinatumomab (an anti-CD19 and anti-CD3 single-chain molecule) to therapy for newly diagnosed standard-risk (as defined by the National Cancer Institute) B-cell ALL in children may improve outcomes.

METHODS

We conducted a phase 3 trial involving children with newly diagnosed standard-risk B-cell ALL who had an average or higher risk of relapse. Patients were randomly assigned to receive chemotherapy alone or chemotherapy plus two nonsequential 28-day cycles of blinatumomab. The primary end point was disease-free survival.

RESULTS

The data and safety monitoring committee reviewed the results from the first interim efficacy analysis, which included 1440 patients who had undergone randomization (722 to chemotherapy alone and 718 to blinatumomab and chemotherapy) and recommended early termination of randomization. At a median follow-up of 2.5 years, the estimated 3-year disease-free survival (±SE) was 96.0±1.2% with blinatumomab and chemotherapy and 87.9±2.1% with chemotherapy alone (difference in restricted mean survival time, 72 days; 95% confidence interval, 36 to 108; P<0.001 by stratified log-rank test). The estimated 3-year disease-free survival among patients with an average relapse risk was 97.5±1.3% with blinatumomab and chemotherapy and 90.2±2.3% with chemotherapy alone; among those with a higher relapse risk, the corresponding values were 94.1±2.5% and 84.8±3.8%. Cytokine release syndrome, seizures, and sepsis of grade 3 or higher were rare during blinatumomab cycles, but the overall incidence of nonfatal sepsis and catheter-related infections was significantly higher among patients with an average relapse risk who had been assigned to receive blinatumomab and chemotherapy than among those assigned to receive chemotherapy alone.

CONCLUSIONS

Adding blinatumomab to combination chemotherapy in patients with newly diagnosed childhood standard-risk B-cell ALL of average or higher risk of relapse significantly improved disease-free survival. (Funded by the National Institutes of Health and others; AALL1731 ClinicalTrials.gov number, NCT03914625.).

JCCG ALL-B12: Evaluation of Intensified Therapies With Vincristine/Dexamethasone Pulses and Asparaginase and Augmented High-Dose Methotrexate for Pediatric B-ALL

PURPOSE

The JCCG ALL-B12 clinical trial aimed to evaluate the effectiveness of unvalidated treatment phases for pediatric ALL and develop a safety-focused treatment framework.

PATIENTS AND METHODS

Patients age 1-19 years with newly diagnosed B-ALL were enrolled in this study. These patients were stratified into standard-risk (SR), intermediate-risk (IR), and high-risk (HR) groups. Randomized comparisons assessed the effectiveness of vincristine (VCR)/dexamethasone pulses in the SR group, evaluated the effects of L-asparaginase (ASP) intensification in the IR group, and compared standard consolidation including block-type treatment with experimental consolidation with high-dose methotrexate (HD-MTX) intensified with VCR and ASP in the HR group.

RESULTS

Of 1,936 patients enrolled, 1,804 were eligible for the experimental treatment. The overall 5-year event-free survival and overall survival rates were 85.2% (95% CI, 83.5 to 86.8) and 94.3% (95% CI, 93.1 to 95.3), respectively. The cumulative incidence of relapse and postremission nonrelapse mortality was 13.2% (95% CI, 11.6 to 14.8) and 0.6% (95% CI, 0.3 to 1.0), respectively. Random assignment in the SR group showed no significant benefit from pulse therapy. In the IR group, ASP intensification had limited effects. In the HR group, standard block therapy and HD-MTX yielded equivalent outcomes.

CONCLUSION

The ALL-B12 trial achieved favorable outcomes in a nationwide cohort by stratifying treatment on the basis of risk and balancing treatment intensity. This study not only demonstrated that existing standard of care can be further refined but also indicated that improvement in outcomes with intensified chemotherapy has reached a plateau.

How I treat Philadelphia chromosome-like acute lymphoblastic leukemia in children, adolescents, and young adults

ABSTRACT

Philadelphia chromosome-like acute lymphoblastic leukemia (Ph-like ALL) represents a high-risk B-lineage ALL subtype characterized by adverse clinical features and poor relapse-free survival despite risk-adapted multiagent chemotherapy regimens. The advent of next-generation sequencing has unraveled the diversity of kinase-activating genetic drivers in Ph-like ALL that are potentially amenable to personalized molecularly-targeted therapies. Based upon robust preclinical data and promising case series of clinical activity of tyrosine kinase inhibitor (TKI)-based treatment in adults and children with relevant genetic Ph-like ALL subtypes, several clinical trials have investigated the efficacy of JAK- or ABL-directed TKIs in cytokine receptor-like factor 2 (CRLF2)/JAK pathway-mutant or ABL-class Ph-like ALL, respectively. The final results of these trials are pending, and standard-of-care therapeutic approaches for patients with Ph-like ALL have yet to be defined. In this How I Treat perspective, we review recent literature to guide current evidence-based treatment recommendations via illustrative clinical vignettes of children, adolescents, and young adults with newly diagnosed or relapsed/refractory Ph-like ALL, and we further highlight open and soon-to-open trials investigating immunotherapy and TKIs specifically for this high-risk patient population.

Health-related Quality of Life in children and adolescents treated for acute lymphoblastic leukaemia (ALL), compared with healthy peers: a longitudinal study of early survivorship

PURPOSE

Survival for childhood Acute Lymphoblastic Leukaemia (ALL) has surpassed 90%, making quality of survival an important endpoint in treatment outcomes. This study examined health-related quality of life (HRQoL) trajectories in early survivorship for patients post-ALL treatment compared with a matched group of healthy peers, and explored the association of individual factors (age, sex) and treatment intensity with HRQoL outcomes.

METHODS

Eighty-three paediatric patients aged 4-16 years who recently completed treatment for ALL were recruited to the study, alongside 53 age- and sex-matched healthy children. All participants completed the self-report Pediatric Quality of Life Inventory (PedsQL) generic score scale at 3-, 15- and 27-months post-study enrolment.

RESULTS

Trajectory of overall HRQoL for the patient group declined over time, falling below clinical cutoffs at 27 months. Subscale trajectories differed between groups, with patients' emotional and social functioning negatively diverging relative to healthy peers, while school functioning remained consistently reduced. Children treated for ALL experienced significantly poorer HRQoL compared to healthy peers at 27 months post-treatment (p = 0.027, ES = - 0.47) with moderate effect sizes, reflecting lower social functioning (p = 0.044, ES = - 0.42) and school functioning (p = 0.011, ES = - 0.52). Age and sex were not associated with overall HRQoL at 27 months; however, younger age was associated with reduced emotional functioning in the standard treatment-intensity group.

CONCLUSION AND IMPLICATIONS

HRQoL is impaired in children treated for ALL in early survivorship, particularly across social and school functioning domains. Screening using patient-reported outcomes is reliable at identifying young people at risk and has potential to guide psychosocial interventions in this early off-treatment period.

Comprehensive genomic characterization of hematologic malignancies at a pediatric tertiary care center

Despite the increasing availability of comprehensive next generation sequencing (NGS), its role in characterizing pediatric hematologic malignancies remains undefined. We describe findings from comprehensive genomic profiling of hematologic malignancies at a pediatric tertiary care center. Patients enrolled on a translational research protocol to aid in cancer diagnosis, prognostication, treatment, and detection of cancer predisposition. Disease-involved samples underwent exome and RNA sequencing and analysis for single nucleotide variation, insertion/deletions, copy number alteration, structural variation, fusions, and gene expression. Twenty-eight patients with hematologic malignancies were nominated between 2018-2021. Eighteen individuals received both germline and somatic sequencing; two received germline sequencing only. Germline testing identified patients with cancer predisposition syndromes and non-cancer carrier states. Fifteen patients (15/18, 83%) had cancer-relevant somatic findings. Potential therapeutic targets were identified in seven patients (7/18, 38.9%); three (3/7, 42.9%) received targeted therapies and remain in remission an average of 47 months later.

Approaches for bridging therapy prior to chimeric antigen receptor T cells for relapsed/refractory acute lymphoblastic B-lineage leukemia in children and young adults

The ongoing development of immunotherapies, including chimeric antigen receptor (CAR) T cells, has revolutionized cancer treatment. In pediatric relapsed/refractory B-lineage acute leukemia antiCD19-CAR induce impressive initial response rates, with event-free survival plateauing at 30-50% according to long-term follow-up data. During the interval between diagnosis of relapse or refractoriness and CAR T-cell infusion, patients require a bridging therapy. To date, this therapy has consisted of highly variable approaches based on local experience. Here, in an European collaborative effort of pediatric and adult hematologists, we summarize current knowledge with the aim of establishing guidance for bridging therapy. We discuss treatment strategies for different subgroups of patients, the advantages and disadvantages of low- and high-intensity regimens, and the potential impact of bridging therapy on outcomes after CAR T-cell infusion. This guidance is a step towards cross-institutional harmonization of bridging therapy, including personalized approaches. This will allow better comparability of clinical data and increase the level of evidence for the treatment of children and young adults with relapsed/ refractory B-lineage acute leukemia until they can receive CAR T-cell infusion.

Enhancing outcomes of childhood acute lymphoblastic leukemia in workplace diversity in Thailand: multicenter study on behalf of the Thai Pediatric Oncology Group

The Thai Pediatric Oncology Group (ThaiPOG) has adapted treatment regimens from the Children's Oncology Group (COG) to enhance outcomes for childhood acute lymphoblastic leukemia (ALL). This study examined the risk factors and treatment results of pediatric ALL in Thailand. This multicenter study included newly diagnosed children (< 18 years) with ALL in 19 centers between January 1, 2015, and December 31, 2019. Most of the 1,157 patients (97.6%) were treated according to ThaiPOG protocols. The genetic testing was performed in 71% of patients. The patients were classified as standard (n = 539), high (n = 402), and very high (n = 130) risks. The 5-year event-free survival (EFS) and overall survival (OS) rates were 75% (95% confidence intervals (CI), 72%-77.8%) and 81.7% (95% CI, 78.9%-84.1%), respectively. The 5-year EFS rates of the standard-, high-, and very high-risk groups were 78.5% (95% CI, 74.1%-82.3%), 73.6% (95% CI, 68.5%-78%) (p = 0.761), and 65% (95% CI, 55.1%-73.3%) (p = 0.001), respectively, and the 5-year OS rates were 86.9% (95% CI, 83.1%-89.9%), 77.3% (95% CI, 72.5%-81.4%) (p = 0.001), and 73.1% (95% CI, 63.7%-80.4%) (p = 0.001), respectively. The independent risk factors for relapse and death were age ≥ 10 years, white blood cells (WBCs) ≥ 50,000/mm3, M2 or M3 marrow status at the end of induction, and high-risk group. The overall outcome of Thai pediatric ALL has improved after the implementation of new modified COG treatment protocols. High-risk characteristics of ALL increased adverse outcome risk.

Heterogeneity of IKZF1 genomic alterations and risk of relapse in childhood B-cell precursor acute lymphoblastic leukemia

Genomic alterations of IKZF1 are common and associated with adverse clinical features in B-ALL. The relationship between the type of IKZF1 alteration, disease subtype and outcome are incompletely understood. Leukemia subtype and genomic alterations were determined using transcriptome and genomic sequencing and SNP microarray in 688 pediatric patients with B-ALL in St. Jude Total Therapy 15 and 16 studies. IKZF1 alterations were identified in 115 (16.7%) patients, most commonly in BCR::ABL1 (78%) and CRLF2-rearranged, BCR::ABL1-like B-ALL (70%). These alterations were associated with 5-year cumulative incidence of relapse (CIR) of 14.8 ± 3.3% compared to 5.0 ± 0.9% for patients without any IKZF1 alteration (P < 0.0001). IKZF1 deletions of exon 4-7 (P = 0.0002), genomic IKZF1 plus with any IKZF1 deletion (P = 0.006) or with focal IKZF1 deletion (P = 0.0007), and unfavorable genomic subtypes (P < 0.005) were independently adversely prognostic factors. Associations of genomic IKZF1 plus and exon 4-7 deletions with adverse outcomes were confirmed in an independent cohort. Genomic IKZF1 plus with any IKZF1 deletion, IKZF1 deletion of exon 4-7, and unfavorable subtype confer increased risk of relapse. The type of IKZF1 alteration, together with the subtype, are informative for risk stratification and predict response in patients with B-ALL.

Harnessing artificial intelligence for the diagnosis and treatment of neurological emergencies: a comprehensive review of recent advances and future directions

Artificial intelligence (AI) is rapidly transforming the landscape of neurology, offering innovative solutions for diagnosing and managing emergent neurological conditions such as stroke, traumatic brain injury, and acute spinal cord injury. This review critically examines the recent advancements in AI applications within the field of neurology, emphasizing both the potential and limitations of these technologies. While AI demonstrates remarkable accuracy and speed in diagnostic imaging, outcome prediction, and personalized treatment plans, its integration into clinical practice remains challenged by ethical concerns, infrastructural limitations, and the "black box" nature of many AI algorithms. The review highlights the current gaps in literature, particularly the limited research on AI's use in low-resource settings and its generalizability across diverse populations. Moreover, the review underscores the need for more longitudinal studies to assess the long-term efficacy of AI-driven interventions and calls for greater transparency in AI systems to enhance trust among clinicians. Future directions for AI in neurology emphasize the importance of interdisciplinary collaboration, regulatory oversight, and the development of equitable AI models that can benefit all patient populations. This review provides a balanced and comprehensive overview of AI's role in neurology, offering insights into both the opportunities and challenges that lie ahead.

Genomic Determinants of Outcome in Acute Lymphoblastic Leukemia

PURPOSE

Although cure rates for childhood acute lymphoblastic leukemia (ALL) exceed 90%, ALL remains a leading cause of cancer death in children. Half of relapses arise in children initially classified with standard-risk (SR) disease.

MATERIALS AND METHODS

To identify genomic determinants of relapse in children with SR ALL, we performed genome and transcriptome sequencing of diagnostic and remission samples of children with SR (n = 1,381) or high-risk B-ALL with favorable cytogenetic features (n = 115) enrolled on Children's Oncology Group trials. We used a case-control study design analyzing 439 patients who relapsed and 1,057 who remained in complete remission for at least 5 years.

RESULTS

Genomic subtype was associated with relapse, which occurred in approximately 50% of cases of PAX5-altered ALL (odds ratio [OR], 3.31 [95% CI, 2.17 to 5.03]; P = 3.18 × 10-8). Within high-hyperdiploid ALL, gain of chromosome 10 with disomy of chromosome 7 was associated with favorable outcome (OR, 0.27 [95% CI, 0.17 to 0.42]; P = 8.02 × 10-10; St Jude Children's Research Hospital validation cohort: OR, 0.22 [95% CI, 0.05 to 0.80]; P = .009), and disomy of chromosomes 10 and 17 with gain of chromosome 6 was associated with relapse (OR, 7.16 [95% CI, 2.63 to 21.51]; P = 2.19 × 10-5; validation cohort: OR, 21.32 [95% CI, 3.62 to 119.30]; P = .0004). Genomic alterations were associated with relapse in a subtype-dependent manner, including alterations of INO80 in ETV6::RUNX1 ALL, IKZF1, and CREBBP in high-hyperdiploid ALL and FHIT in BCR::ABL1-like ALL. Genomic alterations were also associated with the presence of minimal residual disease, including NRAS and CREBBP in high-hyperdiploid ALL.

CONCLUSION

Genetic subtype, patterns of aneuploidy, and secondary genomic alterations determine risk of relapse in childhood ALL. Comprehensive genomic analysis is required for optimal risk stratification.

Impact of Propofol Exposure on Neurocognitive Outcomes in Children With High-Risk B ALL: A Children's Oncology Group Study

PURPOSE

Many children treated for ALL develop long-term neurocognitive impairments. Increased risk of these impairments is associated with treatment and demographic factors. Exposure to anesthesia is an additional possible risk factor. This study evaluated the impact of cumulative exposure to anesthesia on neurocognitive outcomes among a multicenter cohort of children with ALL.

METHODS

This study was embedded in AALL1131, a Children's Oncology Group phase III trial for patients with high-risk B-ALL. In consenting patients age 6-12 years, prospective uniform assessments of neurocognitive function were performed during and at 1 year after completion of therapy. Exposure to all episodes of anesthetic agents was abstracted. Multivariable linear regression models determined associations of cumulative anesthetic agents with the primary neurocognitive outcome reaction time/processing speed (age-normed) at 1 year off therapy, adjusting for baseline neurocognitive score, age, sex, race/ethnicity, insurance status (as a proxy for socioeconomic status), and leukemia risk group.

RESULTS

One hundred and forty-four children, 76 (52.8%) males, mean age of 9.1 (min-max, 6.0-12.0) years at diagnosis, underwent a median of 27 anesthetic episodes (min-max, 1-37). Almost all patients were exposed to propofol (140/144, 97.2%), with a mean cumulative dose of 112.3 mg/kg. One year after therapy, the proportion of children with impairment (Z-score ≤-1.5) was significantly higher compared with a normative sample. In covariate-adjusted multivariable analysis, cumulative exposure to propofol was associated with a 0.05 Z-score decrease in reaction time/processing speed per each 10 mg/kg propofol exposure (P = .03).

CONCLUSION

In a multicenter and uniformly treated cohort of children with B-ALL, cumulative exposure to propofol was an independent risk factor for impairment in reaction time/processing speed 1 year after therapy. Anesthesia exposure is a modifiable risk, and opportunities to minimize propofol use should be considered.

Diagnostic and treatment strategies for pediatric acute lymphoblastic leukemia in low- and middle-income countries

The survival rate of children and adolescents with acute lymphoblastic leukemia (ALL), the most common pediatric cancer, has improved significantly in high-income countries (HICs), serving as an excellent example of how humans can overcome catastrophic diseases. However, the outcomes in children with ALL in low- and middle-income countries (LMICs), where approximately 80% of the global population live, are suboptimal because of limited access to diagnostic procedures, chemotherapeutic agents, supportive care, and financial assistance. Although the implementation of therapeutic strategies in resource-limited countries could theoretically follow the same path of improvement as modeled in HICs, intensification of chemotherapy may simply result in increased toxicities. With the advent of genetic diagnosis, molecular targeted therapy, and immunotherapy, the management of ALL is changing dramatically in HICs. Multidisciplinary collaborations between institutions in LMICs and HICs will provide access to strategies that are suitable for institutions in LMICs, enabling them to minimize toxicities while improving outcomes. This article summarizes important aspects of the diagnosis and treatment of pediatric ALL that were mostly developed in HICs but that can be realistically implemented by institutions in countries with limited resources through resource-adapted multidisciplinary collaborations.

ETV6::RUNX1 Acute Lymphoblastic Leukemia: how much therapy is needed for cure?

Recent trials show 5-year survival rates >95% for ETV6::RUNX1 Acute Lymphoblastic Leukemia (ALL). Since treatment has many side effects, an overview of cumulative drug doses and intensities between eight international trials is presented to characterize therapy needed for cure. A meta-analysis was performed as a comprehensive summary of survival outcomes at 5 and 10 years. For drug dose comparison in non-high risk trial arms, risk group distribution was applied to split the trials into two groups: trial group A with ~70% (range: 63.5-75%) of patients in low risk (LR) (CCLSG ALL2004, CoALL 07-03, NOPHO ALL2008, UKALL2003) and trial group B with ~45% (range: 38.7-52.7%) in LR (AIEOP-BFM ALL 2000, ALL-IC BFM ALL 2002, DCOG ALL10, JACLS ALL-02). Meta-analysis did not show evidence of heterogeneity between studies in trial group A LR and medium risk (MR) despite differences in treatment intensity. Statistical heterogeneity was present in trial group B LR and MR. Trials using higher cumulative dose and intensity of asparaginase and pulses of glucocorticoids and vincristine showed better 5-year event-free survival but similar overall survival. Based on similar outcomes between trials despite differences in therapy intensity, future trials should investigate, to what extent de-escalation is feasible for ETV6::RUNX1 ALL.

IKZF1PLUS alterations contribute to outcome disparities in Hispanic/Latino children with B-lymphoblastic leukemia

BACKGROUND

Compared to other ethnicities, Hispanics/Latinos (H/L) have a high incidence of acute lymphoblastic leukemia (ALL), enrichment of unfavorable ALL genetic subtypes, and worse outcomes, even after correcting for socioeconomic factors. We previously demonstrated increased incidence of the high-risk genetic drivers IKZF1 deletion and IGH::CRLF2 rearrangement in H/L compared to non-H/L children with B-ALL. Here in an expanded pediatric cohort, we sought to identify novel genetic drivers and secondary genetic alterations in B-ALL associated with H/L ethnicity.

PROCEDURE

Comprehensive clinicopathologic data from patients with B-ALL treated from 2016 to 2020 were analyzed. Subtype was determined from karyotype, fluorescence in situ hybridization (FISH), chromosome microarray (CMA), and our next-generation sequencing (NGS) panel (OncoKids). Non-driver genetic variants were also examined. p-Values less than .05 (Fisher's exact test) were considered significant.

RESULTS

Among patients with B-ALL at diagnosis (n = 273), H/L patients (189, 69.2%) were older (p = .018), more likely to present with CNS2 or CNS3 disease (p = .004), and NCI high-risk ALL (p = .014) compared to non-H/L patients. Higher incidence of IGH::CRLF2 rearrangement (B-ALL, BCR::ABL1-like, unfavorable; p = .016) and lower incidence of ETV6::RUNX1 rearrangement (favorable, p = .02) were also associated with H/L ethnicity. Among secondary (non-subtype-defining) genetic variants, B-ALL in H/L was associated with IKFZ1 deletion alone (p = .001) or with IGH::CRLF2 rearrangement (p = .003). The IKZF1PLUS profile (IKZF1 deletion plus CDKN2A/2Bdel, PAX5del, or P2RY8::CRLF2 rearrangement without DUX4 rearrangement) was identified as a novel high-risk feature enriched in H/L patients (p = .001).

CONCLUSIONS

Our study shows enrichment of high-risk genetic variants in H/L B-ALL and raises consideration for novel therapeutic targets.

Disparity in hematological malignancies: From patients to health care professionals

In the recent few decades, outcomes in patients diagnosed with hematological malignancies have been steadily improving. However, the improved prognosis does not distribute equally among patients from different backgrounds. Besides cancer biology, demographic and geographic disparities have been found to impact overall survival significantly. Specifically, patients from underrepresented minorities including Black and Hispanics, and those with uninsured status, having low socioeconomic status, or from rural areas have had worse outcomes historically, which is uniformly true across all major subtypes of hematological malignancies. Similar discrepancy is also seen in the health care professional field, where a gender gap and a disproportionally low representation of health care providers from underrepresented minorities have been long existing. Thus, a comprehensive strategy to mitigate disparity in the health care system is needed to achieve equity in health care.

Treatment of Pediatric Acute Lymphoblastic Leukemia: A Historical Perspective

Acute lymphoblastic leukemia (ALL) is the most common disease in pediatric oncology. The history of developmental therapeutics for ALL began in the 1960s with the repetition of "unreliable" medical interventions against this lethal disease. By the 1990s, the development of multi-agent chemotherapy and various types of supportive care rendered ALL treatable. Highly sophisticated, molecular, diagnostic techniques have enabled highly accurate prediction of the relapse risk, and the application of risk-adapted treatments has increased the survival rate in the standard-risk group to nearly 100% in most European nations and North America. Incorporation of state-of-the-art, molecularly targeted agents and novel treatments, including cell and immunotherapy, is further improving outcomes even in the high-risk group. On the other hand, the financial burden of treating children with ALL has increased, imperiling the availability of these diagnostic and treatment strategies to patients in low- and middle-income countries (LMICs). The fundamental treatment strategy, consisting of corticosteroid and classical cytotoxic therapy, has achieved fairly good outcomes and should be feasible in LMICs as well. The present review will discuss the history of developmental therapeutics for childhood ALL in various countries through an extensive literature review with the aim of proposing a model for a treatment backbone for pediatric ALL. The discussion will hopefully benefit LMICs and be useful as a base for future clinical trials of novel treatments.

Dose-Related Effect of Chemotherapy on Bone Mineral Density Among Pediatric Acute Lymphoblastic Leukemia Survivors

OBJECTIVES

Reduced bone mineral density (BMD) can negatively affect lifelong skeletal health by -increasing the risk for developing osteopenia and osteoporosis. This study evaluated the relationship between BMD and cumulative doses of intravenous (IV) methotrexate (MTX) and glucocorticoids in pediatric acute lymphoblastic leukemia (ALL) survivors. The association between BMD and vitamin D concentrations measured at the time of entry into the long-term follow-up program was also assessed.

METHODS

This retrospective study included pediatric ALL survivors who had received a dual-energy X-ray absorptiometry (DXA) scan after the end of therapy (EOT) or within the 6 months prior to the EOT. Low/-intermediate and high cumulative IV MTX doses were defined as doses less than 20,000 mg/m2 and -greater than or equal to 20,000 mg/m2, respectively. Descriptive statistics, Student t test, and linear -regression were used to analyze the data.

RESULTS

A total of 62 patients, with 34 patients in the low/intermediate and 28 patients in the high -cumulative IV MTX dose groups, were analyzed. The median time from EOT to DXA scan was 2.3 years. The mean DXA lumbar spine z score was significantly lower in the high cumulative IV MTX dose group -compared with the low/intermediate dose group (-0.86 vs -0.14; p = 0.008). Cumulative glucocorticoid doses and vitamin D concentrations were not associated with BMD.

CONCLUSIONS

Pediatric patients who had received cumulative IV MTX doses of greater than or equal to 20,000 mg/m2 during their ALL treatment had lower BMD than those who had received lower cumulative doses.

Development of osteonecrosis and improved survival in B-ALL: results of Children's Oncology Group Trial AALL0232

Osteonecrosis is a significant toxicity of acute lymphoblastic leukemia (ALL) therapy. In retrospective analyses, superior event-free survival was noted among affected adolescents in an earlier trial. We prospectively assessed osteonecrosis incidence, characteristics, and risk factors in patients 1-30 years with newly diagnosed high-risk B-ALL on COG AALL0232. Patients were randomized to induction dexamethasone vs prednisone, and interim maintenance high-dose methotrexate vs escalating-dose Capizzi methotrexate/pegaspargase. Event-free and overall survival were compared between patients with/without imaging-confirmed osteonecrosis. Osteonecrosis developed in 322/2730 eligible, evaluable patients. The 5-year cumulative incidence was 12.2%. Risk was greater in patients ≥10 years (hazard ratio [HR], 7.23; P < 0.0001), particularly females (HR, 1.37; P = 0.0057), but lower in those with asparaginase allergy (HR, 0.60; P = 0.0077). Among rapid early responders ≥10 years, risk was greater with dexamethasone (HR, 1.84; P = 0.0003) and with prednisone/Capizzi (HR, 1.45; P = 0.044), even though neither therapy was independently associated with improved survival. Patients with osteonecrosis had higher 5-year event-free (HR, 0.51; P < 0.0001) and overall survival (HR, 0.42; P < 0.0001), and this was directly attributable to reduced relapse rates (HR, 0.57; P = 0.0014). Osteonecrosis in high-risk B-ALL patients is associated with improved survival, suggesting an important role for host factors in mediating both toxicity and enhanced efficacy of specific therapies.

Outcomes in Children, Adolescents, and Young Adults With Down Syndrome and ALL: A Report From the Children's Oncology Group

PURPOSE

Patients with Down syndrome (DS) and B-ALL experience increased rates of relapse, toxicity, and death. We report results for patients with DS B-ALL enrolled on Children's Oncology Group trials between 2003 and 2019.

METHODS

We analyzed data for DS (n = 743) and non-DS (n = 20,067) patients age 1-30 years on four B-ALL standard-risk (SR) and high-risk trials.

RESULTS

Patients with DS exhibited more frequent minimal residual disease (MRD) ≥0.01% at end induction (30.8% v 21.5%; P < .001). This difference persisted at end consolidation only in National Cancer Institute (NCI) high-risk patients (34.0% v 11.7%; P < .0001). Five-year event-free survival (EFS) and overall survival (OS) were significantly poorer for DS versus non-DS patients overall (EFS, 79.2% ± 1.6% v 87.5% ± 0.3%; P < .0001; OS, 86.8% ± 1.4% v 93.6% ± 0.2%; P < .0001), and within NCI SR and high-risk subgroups. Multivariable Cox regression analysis of the DS cohort for risk factors associated with inferior EFS identified age >10 years, white blood count >50 × 103/μL, and end-induction MRD ≥0.01%, but not cytogenetics or CRLF2 overexpression. Patients with DS demonstrated higher 5-year cumulative incidence of relapse (11.5% ± 1.2% v 9.1% ± 0.2%; P = .0008), death in remission (4.9% ± 0.8% v 1.7% ± 0.1%; P < .0001), and induction death (3.4% v 0.8%; P < .0001). Mucositis, infections, and hyperglycemia were significantly more frequent in all patients with DS, while seizures were more frequent in patients with DS on high-risk trials (4.1% v 1.8%; P = .005).

CONCLUSION

Patients with DS-ALL exhibit an increased rate of relapse and particularly of treatment-related mortality. Novel, less-toxic therapeutic strategies are needed to improve outcomes.

Acute Lymphoblastic Leukemia with Central Nervous System Involvement-Challenges in Management

The survival of patients with acute lymphoblastic leukemia (ALL) has dramatically improved during the last six decades. This improvement is secondary to improved diagnostics, risk stratification of treatment by biological features and response to treatment, improved supportive care, and the introduction of new treatment modalities such as immunotherapy and molecular targeted therapy. However, many questions remain concerning the involvement of the central nervous system (CNS) in leukemia, including ones pertaining to the risk factors for CNS involvement and relapse, the optimal treatment strategy to prevent relapse, and the role of newer therapies. This review discusses these questions by addressing the diagnosis of CNS leukemia, the current clinical trial data for treatment regimens with CNS activity, and issues specific to treatment in low- and middle-income countries (LMICs).

Advancing Diagnostics and Therapy to Reach Universal Cure in Childhood ALL

Systemic combination chemotherapy and intrathecal chemotherapy markedly increased the survival rate of children with ALL. In the past two decades, the use of minimal (measurable) residual disease (MRD) measurements early in therapy improved risk group stratification with subsequent treatment intensifications for patients at high risk of relapse, and enabled a reduction of treatment for low-risk patients. The recent development of more sensitive MRD technologies may further affect risk stratification. Molecular genetic profiling has led to the discovery of many new subtypes and their driver genetic alterations. This increased our understanding of the biological basis of ALL, improved risk classification, and enabled implementation of precision medicine. In the past decade, immunotherapies, including bispecific antibodies, antibody-drug conjugates, and cellular therapies directed against surface proteins, led to more effective and less toxic therapies, replacing intensive chemotherapy courses and allogeneic stem-cell transplantation in patients with relapsed and refractory ALL, and are now being tested in newly diagnosed patients. It has taken 50-60 years to increase the cure rate in childhood ALL from 0% to 90% by stepwise improvements in chemotherapy. This review provides an overview of how the developments over the past 10-15 years mentioned above have significantly changed the diagnostic and treatment approach in ALL, and discusses how the integrated use of molecular and immunotherapeutic insights will very likely direct efforts to cure those children with ALL who are not cured today, and improve the quality of life for survivors who should have decades of life ahead. Future efforts must focus on making effective, yet very expensive, new technologies and therapies available to children with ALL worldwide.

Prognostic significance of ETP phenotype and minimal residual disease in T-ALL: a Children's Oncology Group study

The early thymic precursor (ETP) immunophenotype was previously reported to confer poor outcome in T-cell acute lymphoblastic leukemia (T-ALL). Between 2009 and 2014, 1256 newly diagnosed children and young adults enrolled in Children's Oncology Group (COG) AALL0434 were assessed for ETP status and minimal residual disease (MRD) using flow cytometry at a central reference laboratory. The subject phenotypes were categorized as ETP (n = 145; 11.5%), near-ETP (n = 209; 16.7%), or non-ETP (n = 902; 71.8%). Despite higher rates of induction failure for ETP (6.2%) and near-ETP (6.2%) than non-ETP (1.2%; P < .0001), all 3 groups showed excellent 5-year event-free survival (EFS) and overall survival (OS): ETP (80.4% ± 3.9% and 86.8 ± 3.4%, respectively), near-ETP (81.1% ± 3.3% and 89.6% ± 2.6%, respectively), and non-ETP (85.3% ± 1.4% and 90.0% ± 1.2%, respectively; P = .1679 and P = .3297, respectively). There was no difference in EFS or OS for subjects with a day-29 MRD <0.01% vs 0.01% to 0.1%. However, day-29 MRD ≥0.1% was associated with inferior EFS and OS for patients with near-ETP and non-ETP, but not for those with ETP. For subjects with day-29 MRD ≥1%, end-consolidation MRD ≥0.01% was a striking predictor of inferior EFS (80.9% ± 4.1% vs 52.4% ± 8.1%, respectively; P = .0001). When considered as a single variable, subjects with all 3 T-ALL phenotypes had similar outcomes and subjects with persistent postinduction disease had inferior outcomes, regardless of their ETP phenotype. This clinical trial was registered at AALL0434 as #NCT00408005.

A Review of Acute Lymphocytic Leukemia (ALL) in the Pediatric Population: Evaluating Current Trends and Changes in Guidelines in the Past Decade

Acute lymphocytic leukemia (ALL) is a commonly diagnosed cancer in children. Despite technological advancements to improve treatment and survival rates, there has been a steady increase in the incidence of ALL and treatment failures. This paper discusses the pathogenic interaction between genetic and environmental factors leading to childhood ALL. It evaluates the current treatment guidelines and notable obstacles leading to resistance, relapse, and treatment toxicities. The review evaluates a 10-year trend in the management guidelines of pediatric ALL through a systematic literature review of records from 2012 to 2023. Findings show that improvement in the five-year survival rates, notwithstanding rates of relapse and incurable diseases, is still high. Furthermore, several risk factors, including an interplay between genetic and environmental factors, are largely contributory to the outcome of ALL treatments and its overall incidence. Moreover, huge financial costs have remained a significant challenge in outcomes. There remains a need to provide individualized treatment plans, shared decision-making, and goals of care as parts of the management guidelines for the best possible outcomes. We expect that future advancements will increase overall survival rates and disease-free years.

Children's Oncology Group's 2023 blueprint for research: Cancer control and supportive care

The objective of the Cancer Control and Supportive Care (CCL) Committee in the Children's Oncology Group (COG) is to reduce the overall morbidity and mortality of therapy-related toxicities in children, adolescents, and young adults with cancer. We have targeted five major domains that cause clinically important toxicity: (i) infections and inflammation; (ii) malnutrition and metabolic dysfunction; (iii) chemotherapy-induced nausea and vomiting; (iv) neuro- and oto-toxicty; and (v) patient-reported outcomes and health-related quality of life. Subcommittees for each domain prioritize randomized controlled trials and biology aims to determine which strategies best mitigate the toxicities. The findings of these trials are impactful, informing clinical practice guidelines (CPGs) and directly leading to changes in the standard of care for oncology practice. With the development of new therapies, there will be new toxicities, and the COG CCL Committee is dedicated to developing interventions to minimize acute and delayed toxicities, lessen morbidity and mortality, and improve quality of life in pediatric and young adult patients with cancer.

Inotuzumab ozogamicin in B-cell precursor acute lymphoblastic leukemia: efficacy, toxicity, and practical considerations

Inotuzumab ozogamicin (InO) is an antibody drug conjugate composed of a humanized monoclonal antibody targeting the cell surface receptor CD22 coupled to a cytotoxic calicheamicin payload via an acid labile linker. InO has shown significant activity in relapsed and refractory B-cell precursor acute lymphoblastic leukemia (BCP-ALL) in both single agent and combination chemotherapy regimens in adult and pediatric trials. Its use in newly diagnosed elderly patients has also been established while clinical trials investigating its use in newly diagnosed pediatric patients and fit adults are ongoing. Notable toxicities include sinusoidal obstruction syndrome (SOS), particularly in patients who undergo hematopoietic stem cell transplantation (HSCT) after InO as well as myelosuppression and B-cell aplasia which confer increased infection risk, particularly in combination with cytotoxic chemotherapy. In the relapsed/refractory (R/R) setting, the planned subsequent curative therapy modality must be considered when using InO to mitigate SOS risk if proceeding to HSCT and account for potential B-cell aplasia if proceeding to chimeric antigen receptor CAR-T therapy. Studies exploring mechanisms of resistance or failure of InO are ongoing but modulation or loss CD22 expression, alternative CD22 splicing, and high Bcl-2 expression have been implicated. In this review, we will summarize the currently available data on InO, with an emphasis on pediatric trials, and explore future directions including combinatorial therapy.

Poverty and relapse risk in children with acute lymphoblastic leukemia: a Children's Oncology Group study AALL03N1 report

The association between individual-level poverty and relapse in children receiving maintenance treatment for acute lymphoblastic leukemia (ALL) remains unclear. In a secondary analysis of COG-AALL03N1, we used data from US Census Bureau to categorize patients living below year-specific federal poverty thresholds, calculated using self-reported annual household income and size of household. Participants with federal poverty thresholds above 120% of their yearly household income were categorized as living in extreme poverty. Hazard of relapse was estimated using multivariable proportional subdistributional hazards regression for patients living in extreme poverty while receiving ALL maintenance therapy after adjusting for relevant predictors. Among 592 patients in this analysis, 12.3% of the patients were living in extreme poverty. After a median follow-up of 7.9 years, the cumulative incidence of relapse at 3 years from study enrollment among those living in extreme poverty was significantly higher (14.3%) than those not living in extreme poverty (7.6%). Multivariable analysis demonstrated that children living in extreme poverty had a 1.95-fold greater hazard of relapse than those not living in extreme poverty; this association was mitigated after the inclusion of race/ethnicity in the model, likely because of collinearity between race/ethnicity and poverty. A greater proportion of children living in extreme poverty were nonadherent to mercaptopurine (57.1% vs 40.9%); however, poor adherence did not completely explain the association between poverty and relapse risk. Future studies need to understand the mechanisms underlying the association between extreme poverty and relapse risk. This trial was registered at www.clinicaltrials.gov as #NCT00268528.

Dasatinib with intensive chemotherapy in de novo paediatric Philadelphia chromosome-positive acute lymphoblastic leukaemia (CA180-372/COG AALL1122): a single-arm, multicentre, phase 2 trial

BACKGROUND

The outcome of children with Philadelphia chromosome-positive (Ph-positive) acute lymphoblastic leukaemia significantly improved with the combination of imatinib and intensive chemotherapy. We aimed to investigate the efficacy of dasatinib, a second-generation ABL-class inhibitor, with intensive chemotherapy in children with newly diagnosed Ph-positive acute lymphoblastic leukaemia.

METHODS

CA180-372/COG AALL1122 was a joint Children's Oncology Group (COG) and European intergroup study of post-induction treatment of Ph-positive acute lymphoblastic leukaemia (EsPhALL) open-label, single-arm, phase 2 study. Eligible patients (aged >1 year to <18 years) with newly diagnosed Ph-positive acute lymphoblastic leukaemia and performance status of at least 60% received EsPhALL chemotherapy plus dasatinib 60 mg/m² orally once daily from day 15 of induction. Patients with minimal residual disease of at least 0·05% after induction 1B or who were positive for minimal residual disease after the three consolidation blocks were classified as high risk and allocated to receive haematopoietic stem-cell transplantation (HSCT) in first complete remission. The remaining patients were considered standard risk and received chemotherapy plus dasatinib for 2 years. The primary endpoint was the 3-year event-free survival of dasatinib plus chemotherapy compared with external historical controls. The trial was considered positive if one of the following conditions was met: superiority over chemotherapy alone in the AIEOP-BFM 2000 high-risk group; or non-inferiority (with a margin of -5%) or superiority to imatinib plus chemotherapy in the EsPhALL 2010 cohort. All participants who received at least one dose of dasatinib were included in the safety and efficacy analyses. This trial was registered with ClinicalTrials.gov, NCT01460160, and recruitment is closed.

FINDINGS

Between March 13, 2012, and May 27, 2014, 109 patients were enrolled at 69 sites (including 51 COG sites in the USA, Canada, and Australia, and 18 EsPhALL sites in Italy and the UK). Three patients were ineligible and did not receive dasatinib. 106 patients were treated and included in analyses (49 [46%] female and 57 [54%] male; 85 [80%] White, 13 [12%] Black or African American, five [5%] Asian, and three [3%] other races; 24 [23%] Hispanic or Latino ethnicity). All 106 treated patients reached complete remission; 87 (82%) were classified as standard risk and 19 (18%) met HSCT criteria and were classified as high risk, but only 15 (14%) received HSCT in first complete remission. The 3-year event-free survival of dasatinib plus chemotherapy was superior to chemotherapy alone (65·5% [90% Clopper-Pearson CI 57·7 to 73·7] vs 49·2% [38·0 to 60·4]; p=0·032), and was non-inferior to imatinib plus chemotherapy (59·1% [51·8 to 66·2], 90% CI of the treatment difference: -3·3 to 17·2), but not superior to imatinib plus chemotherapy (65·5% vs 59·1%; p=0·27). The most frequent grade 3-5 adverse events were febrile neutropenia (n=93) and bacteraemia (n=21). Nine remission deaths occurred, which were due to infections (n=5), transplantation-related (n=2), due to cardiac arrest (n=1), or had an unknown cause (n=1). No dasatinib-related deaths occurred.

INTERPRETATION

Dasatinib plus EsPhALL chemotherapy is safe and active in paediatric Ph-positive acute lymphoblastic leukaemia. 3-year event-free survival was similar to that of previous Ph-positive acute lymphoblastic leukaemia trials despite the limited use of HSCT in first complete remission.

FUNDING

Bristol Myers Squibb.

Real-world practice of acute leukemia intrathecal chemotherapy administration: A Mexican nationwide survey

INTRODUCTION

Intrathecal chemotherapy is a mainstay component of acute lymphoblastic leukemia treatment. In Mexico, there is a considerable practice variability in aspects, such as the manner of preparation and the administration technique.

OBJECTIVE

Our objective was to describe the different techniques used for the application of ITC and review the existing recommendations in the literature.

METHOD

A cross-sectional, nationwide survey study was conducted by an electronic questionnaire sent to hematologists and oncologists in Mexico. We collected demographic data, personal experience, intrathecal chemotherapy techniques, drug preparation and postprocedural conduct.

RESULTS

We received 173 responses. Twenty percent had an anesthesiologist administering sedation and pain management. The platelet count considered safe was 50 × 109/L in 48% of the participants. In 77% (n = 133) of the cases, the conventional needle with stylet used was, 49% did not receive any added diluent in the intrathecal chemotherapy and only 42% were recommended to rest in a horizontal position for more than 30 min.

CONCLUSION

We identified a considerable variation in the administration of intrathecal chemotherapy across the hematologists in Mexico. We discuss the implications and opportunities in reducing the variation in our setting, highlighting the unmet need to establish guidelines that should be evaluated by the Mexican professional society to produce a position paper regarding practice standardization.

Impaired neurocognitive functioning 3 months following diagnosis of high-risk acute lymphoblastic leukemia: A report from the Children's Oncology Group

PURPOSE

Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer diagnosis. Cognitive late effects develop in 20%-40% of ALL survivors, but the course of declines is unclear. The aim of this paper is to characterize cognitive functioning, and its association with patient-reported outcomes, early in treatment.

PATIENTS AND METHODS

A total of 483 children with high-risk ALL, aged 6-12 years at diagnosis, consented to the neurocognitive study embedded in a prospective therapeutic trial, Children's Oncology Group (COG) AALL1131. A computerized neurocognitive battery (Cogstate) was administered 3 months post diagnosis assessing reaction time, visual attention, working memory, visual learning, and executive functioning. Parent-reported executive functioning and patient-reported physical symptoms were also collected.

RESULTS

Data from 390 participants (mean age at diagnosis = 9.2 years, 55.4% male) were obtained. Relatively few patients reported pain (16.0%) or nausea (22.6%), but a majority (68.5%) reported feeling at least some fatigue at testing. Mean Cogstate Z-scores were within normal limits across tasks; however, rates of impairment (Z-scores ≤ -1.5) for reaction time, working memory, visual learning, and visual attention were all higher than expected compared to the standardization sample. Patients reporting fatigue were significantly more likely to have impaired reaction time and visual attention compared to those reporting no fatigue.

CONCLUSION

Findings support feasibility of computerized cognitive assessments and suggest higher-than-expected rates of impaired cognitive performance early during treatment for pediatric ALL, notably within 3 months of diagnosis, suggesting intervention efforts may be indicated. These results also highlight acute factors that may impact reliability of "baseline" assessments conducted soon after diagnosis.

CXCR4 antagonists disrupt leukaemia-meningeal cell adhesion and attenuate chemoresistance

The effective prophylaxis and treatment of central nervous system (CNS) involvement in acute lymphoblastic leukaemia (ALL) remains a significant clinical challenge. Developing novel and more effective CNS-directed therapies has been hampered, in part, by our limited understanding of the leukaemia niche in the CNS relative to the bone marrow. Accordingly, defining the molecular and cellular components critical for the establishment and maintenance of the CNS leukaemia niche may lead to new therapeutic opportunities. In prior work we showed that direct intercellular interactions between leukaemia and meningeal cells enhance leukaemia chemoresistance in the CNS. Herein, we show that the CXCR4/CXCL12 chemokine axis contributes to leukaemia-meningeal cell adhesion. Importantly, clinically tested CXCR4 antagonists, which are likely to cross the blood-brain and blood-cerebral spinal fluid barriers and penetrate the CNS, effectively disrupted leukaemia-meningeal cell adhesion. Moreover, by disrupting these intercellular interactions, CXCR4 antagonists attenuated leukaemia chemoresistance in leukaemia-meningeal cell co-culture experiments and enhanced the efficacy of cytarabine in targeting leukaemia cells in the meninges in vivo. This work identifies the CXCR4/CXCL12 axis as an important regulator of intercellular interactions within the CNS leukaemia niche and supports further testing of the therapeutic efficacy of CXCR4 antagonists in overcoming CNS niche-mediated chemoresistance.

Ethnic-specific predictors of neurotoxicity among patients with pediatric acute lymphoblastic leukemia after high-dose methotrexate

BACKGROUND

High-dose methotrexate (HD-MTX; 5000 mg/m2 ) is an important component of curative therapy in many treatment regimens for high-risk pediatric acute lymphoblastic leukemia (ALL). However, methotrexate therapy can result in dose-limiting neurotoxicity, which may disproportionately affect Latino children. This study evaluated risk factors for neurotoxicity after HD-MTX in an ethnically diverse population of patients with ALL.

METHODS

The authors retrospectively reviewed the medical records of patients who were diagnosed with ALL and treated with HD-MTX at Texas Children's Cancer Center (2010-2017). Methotrexate neurotoxicity was defined as a neurologic episode (e.g., seizures or stroke-like symptoms) occurring within 21 days of HD-MTX that resulted in methotrexate treatment modifications. Mixed effects multivariable logistic regression was used to estimate the odds ratio (OR) and corresponding 95% confidence interval (CI) for the association between clinical factors and neurotoxicity.

RESULTS

Overall, 351 patients (58.1% Latino) who received 1183 HD-MTX infusions were evaluated. Thirty-five patients (10%) experienced neurotoxicity, 71% of whom were Latino. After adjusting for clinical risk factors, the authors observed that serum creatinine elevations ≥50% of baseline were associated with a three-fold increased odds (OR, 3.32; 95% CI, 0.98-11.21; p = .05) for neurotoxicity compared with creatinine elevation <25%. Notably, predictors of neurotoxicity differed by ethnicity. Specifically, Latino children experienced a nearly six-fold increase in neurotoxicity odds (OR, 5.80; 95% CI, 1.39-24.17; p = .02) with serum creatinine elevation ≥50% compared with creatinine elevation <25%.

CONCLUSIONS

The current findings indicate that serum creatinine elevations ≥50% may be associated with an increased risk for neurotoxicity among Latino children with ALL and may identify potential candidates for therapeutic or supportive care interventions.

Central nervous system status is prognostic in T-cell acute lymphoblastic leukemia: a Children's Oncology Group report

To determine the prognostic significance of central nervous system (CNS) leukemic involvement in newly diagnosed T-cell acute lymphoblastic leukemia (T-ALL), outcomes on consecutive, phase 3 Children's Oncology Group clinical trials were examined. AALL0434 and AALL1231 tested efficacy of novel agents within augmented-Berlin-Frankfurt-Münster (aBFM) therapy. In addition to testing study-specific chemotherapy through randomization, the AALL0434 regimen delivered cranial radiation therapy (CRT) to most participants (90.8%), whereas AALL1231 intensified chemotherapy to eliminate CRT in 88.2% of participants. In an analysis of 2164 patients with T-ALL (AALL0434, 1550; AALL1231, 614), 1564 had CNS-1 (72.3%), 441 CNS-2 (20.4%), and 159 CNS-3 (7.3%). The 4-year event-free-survival (EFS) was similar for CNS-1 (85.1% ± 1.0%) and CNS-2 (83.2% ± 2.0%), but lower for CNS-3 (71.8% ± 4.0%; P = .0004). Patients with CNS-1 and CNS-2 had similar 4-year overall survival (OS) (90.1% ± 0.8% and 90.5% ± 1.5%, respectively), with OS for CNS-3 being 82.7% ± 3.4% (P = .005). Despite therapeutic differences, outcomes for CNS-1 and CNS-2 were similar regardless of CRT, intensified corticosteroids, or novel agents. Except for significantly superior outcomes with nelarabine on AALL0434 (4-year disease-free survival, 93.1% ± 5.2%), EFS/OS was inferior with CNS-3 status, all of whom received CRT. Combined analyses of >2000 patients with T-ALL identified that CNS-1 and CNS-2 status at diagnosis had similar outcomes. Unlike B-ALL, CNS-2 status in T-ALL does not impact outcome with aBFM therapy, without additional intrathecal therapy, with or without CRT. Although nelarabine improved outcomes for those with CNS-3 status, novel approaches are needed. These trials were registered at www.clinicaltrials.gov as #NCT00408005 (AALL0434) and #NCT02112916 (AALL1231).

How I prevent and treat central nervous system disease in adults with acute lymphoblastic leukemia

The central nervous system (CNS) is the most important site of extramedullary disease in adults with acute lymphoblastic leukemia (ALL). Although CNS disease is identified only in a minority of patients at the time of diagnosis, subsequent CNS relapses (either isolated or concurrent with other sites) occur in some patients even after the delivery of prophylactic therapy targeted to the CNS. Historically, prophylaxis against CNS disease has included intrathecal (IT) chemotherapy and radiotherapy (RT), although the latter is being used with decreasing frequency. Treatment of a CNS relapse usually involves intensive systemic therapy and cranial or craniospinal RT along with IT therapy and consideration of allogeneic hematopoietic cell transplant. However, short- and long-term toxicities can make these interventions prohibitively risky, particularly for older adults. As new antibody-based immunotherapy agents have been approved for relapsed/refractory B-cell ALL, their use specifically for patients with CNS disease is an area of keen interest not only because of the potential for efficacy but also concerns of unique toxicity to the CNS. In this review, we discuss data-driven approaches for these common and challenging clinical scenarios as well as highlight how recent findings potentially support the use of novel immunotherapeutic strategies for CNS disease.

Racial and ethnic disparities in childhood and young adult acute lymphocytic leukaemia: secondary analyses of eight Children's Oncology Group cohort trials

BACKGROUND

Previous studies have identified racial and ethnic disparities in childhood acute lymphocytic leukaemia survival. We aimed to establish whether disparities persist in contemporaneous cohorts and, if present, are attributable to differences in leukaemia biology or insurance status.

METHODS

Patients with newly diagnosed acute lymphocytic leukaemia in inpatient and outpatient centres in the USA, Canada, Australia, and New Zealand, aged 0-30 years, who had race or ethnicity data available, enrolled on eight completed Children's Oncology Group trials (NCT00103285, NCT00075725, NCT00408005, NCT01190930, NCT02883049, NCT02112916, NCT02828358, and NCT00557193) were included in this secondary analysis. Race and ethnicity were categorised as non-Hispanic White, Hispanic, non-Hispanic Black, non-Hispanic Asian, and non-Hispanic other. Event-free survival and overall survival were compared across race and ethnicity groups. The relative contribution of clinical and biological disease prognosticators and insurance status was examined through multivariable regression models, both among the entire cohort and among those with B-cell lineage versus T-cell lineage disease.

FINDINGS

Between Jan 1, 2004, and Dec 31, 2019, 24 979 eligible children, adolescents, and young adults with acute lymphocytic leukaemia were enrolled, of which 21 152 had race or ethnicity data available. 11 849 (56·0%) were male and 9303 (44·0%) were female. Non-Hispanic White patients comprised the largest racial or ethnic group (13 872 [65·6%]), followed by Hispanic patients (4354 [20·6%]), non-Hispanic Black patients (1517 [7·2%]), non-Hispanic Asian (n=1071 [5·1%]), and non-Hispanic other (n=338 [1·6%]). 5-year event-free survival was 87·4% (95% CI 86·7-88·0%) among non-Hispanic White patients compared with 82·8% (81·4-84·1%; hazard ratio [HR] 1·37, 95% CI 1·26-1·49; p<0·0001) among Hispanic patients and 81·8% (79·3-84·0; HR 1·45, 1·28-1·65; p<0·0001) among non-Hispanic Black patients. Non-hispanic Asian patients had a 5-year event-free survival of 88·1% (95% CI 85·5-90·3%) and non-Hispanic other patients had a survival of 82·8% (76·4-87·6%). Inferior event-free survival among Hispanic patients was substantially attenuated by disease prognosticators and insurance status (HR decreased from 1·37 [1·26-1·49; p<0·0001] to 1·11 [1·00-1·22; p=0·045]). The increased risk among non-Hispanic Black patients was minimally attenuated (HR 1·45 [1·28-1·65; p<0·0001] to 1·32 [1·14-1·52; p<0·0001]). 5-year overall survival was 93·6% (91·5-95·1%) in non-Hispanic Asian patients, 93·3% (92·8-93·7%) in non-Hispanic White patients, 89·9% (88·7-90·9%) in Hispanic, 89·7% (87·6-91·4%) in non-Hispanic Black patients, 88·9% (83·2-92·7%) in non-Hispanic other patients. Disparities in overall survival were wider than event-free survival (eg, among non-Hispanic other patients, the HR for event-free survival was 1·43 [1·10-1·85] compared with 1·74 [1·27-2·40] for overall survival). Disparities were restricted to patients with B-cell acute lymphocytic leukaemia, no differences in event-free survival or overall survival were seen in the T-cell acute lymphocytic leukaemia group.

INTERPRETATION

Substantial disparities in outcome for B-cell acute lymphocytic leukaemia persist by race and ethnicity, but are not observed in T-cell acute lymphocytic leukaemia. Future studies of relapsed patients, access to and quality of care, and other potential aspects of structural racism are warranted to inform interventions aimed at dismantling racial and ethnic disparities.

FUNDING

National Cancer Institute and St Baldrick's Foundation.

Recent progress in pediatric lymphoblastic leukemia

The probability of long-term survival for children with lymphoblastic leukemia has improved dramatically over recent decades, mainly owing to advances in genomic analysis techniques, which have improved our understanding of the nature of leukemic cells and prognostic prediction based on the evaluation of precise treatment response. Risk-adjusted chemotherapy based on these advances has simultaneously reduced relapse rates and minimized complications. In addition, recent genomic analyses have deepened our understanding of the pathogenesis of leukemia and revealed the involvement of germline variations in the clinical course of leukemia treatment. Additionally, advances in minimal residual disease assays and the introduction of immunotherapy are expected to further improve therapeutic analyses. Further advances in clinical and translational research are anticipated to improve survival to 100% in a healthy state.

Body mass index during maintenance therapy and relapse risk in children with acute lymphoblastic leukemia: A Children's Oncology Group report

BACKGROUND

Obesity at diagnosis of childhood acute lymphoblastic leukemia (ALL) is associated with greater risk of relapse; whether this association extends to obesity during maintenance is unstudied.

METHODS

This study used data from AALL03N1 to calculate median body mass index (BMI) for 676 children over 6 consecutive months during maintenance therapy; BMI percentile (BMI%ile) were operationalized as normal/underweight (<85%ile), overweight/obese (85%-98%ile), and extreme obesity (≥99%ile). Hazard of relapse was estimated using multivariable proportional subdistributional hazards regression after adjusting for all relevant demographic and clinical predictors.

RESULTS

Median age at study enrollment was 6 years and median length of follow-up was 7.9 years. Overall, 43.3% of the cohort was underweight/normal weight, 44.8% was overweight/obese, and 11.8% had extreme obesity. Cumulative incidence of relapse at 4 years from study enrollment was higher among those with extreme obesity (13.6% ± 4.5%) compared to those with underweight/normal weight (9.0% ± 2.1%). Multivariable analysis revealed that children with extreme obesity had a 2.4-fold (95% confidence interval [CI], 1.1-5.0; p = .01) greater hazard of relapse compared to those who were underweight/normal weight. Overweight/obese patients were at comparable risk to those who were underweight/normal weight (hazard ratio, 0.8; 95% CI, 0.4-1.6). Erythrocyte thioguanine nucleotide (TGN) levels were significantly lower among children with extreme obesity compared to those with underweight/normal weight (141.6 vs. 168.8 pmol/8 × 108 erythrocytes; p = .0002), however, the difference in TGN levels did not explain the greater hazard of relapse among those with extreme obesity.

CONCLUSIONS

Extreme obesity during maintenance therapy is associated with greater hazard of relapse in children with ALL. Underlying mechanisms of this association needs further investigation.

LAY SUMMARY

Findings from this study demonstrate that extreme obesity during maintenance therapy is associated with a greater hazard of relapse among children with acute lymphoblastic leukemia. We show that children with obesity have lower levels of erythrocyte thioguanine nucleotides even after adjusting for adherence to oral chemotherapy. However, these lower levels do not explain the greater hazard of relapse, paving the way for future studies to explore this association.

Clinical and demographic factors contributing to asparaginase-associated toxicities in children with acute lymphoblastic leukemia

A total of 548 patients (age range: 1-22 years, 60.4% Hispanic, 55.8% male) diagnosed with acute lymphoblastic leukemia were reviewed for pegaspargase-associated hypersensitivity (14.8%), hyperbilirubinemia (9.7%), venous thromboembolism (VTE, 9.7%), and pancreatitis (5.3%). Odds ratios (OR) and 95% confidence intervals (CI) evaluated associations between clinical factors and each toxicity, cumulative number of toxicities, and toxicity clusters identified using k-mode analysis. Most (68.9%) did not experience any toxicity, 24.6% experienced one toxicity, and 6.3% two or more. Age >10 years was associated with hyperbilirubinemia (OR = 3.83; 95% CI: 1.64-8.95), pancreatitis (OR = 3.72; 95% CI: 1.29-10.68), VTE (OR = 4.65; 95% CI: 1.96-11.02), and cumulative toxicity burden (OR = 3.28, 95% CI: 1.97-5.47); high-risk therapy with hypersensitivity (OR 2.25; 95% CI 1.25-4.05); and overweight with cumulative toxicity burden (OR = 1.76, 95% CI: 1.20-2.57). Eight unique toxicity profiles were identified. Older age, overweight, and treatment intensity contribute to pegaspargase-associated toxicities.

Central nervous system involvement in childhood acute lymphoblastic leukemia: challenges and solutions

Delivery of effective anti-leukemic agents to the central nervous system (CNS) is considered essential for cure of childhood acute lymphoblastic leukemia. Current CNS-directed therapy comprises systemic therapy with good CNS-penetration accompanied by repeated intrathecal treatments up to 26 times over 2-3 years. This approach prevents most CNS relapses, but is associated with significant short and long term neurotoxicity. Despite this burdensome therapy, there have been no new drugs licensed for CNS-leukemia since the 1960s, when very limited anti-leukemic agents were available and there was no mechanistic understanding of leukemia survival in the CNS. Another major barrier to improved treatment is that we cannot accurately identify children at risk of CNS relapse, or monitor response to treatment, due to a lack of sensitive biomarkers. A paradigm shift in treating the CNS is needed. The challenges are clear - we cannot measure CNS leukemic load, trials have been unable to establish the most effective CNS treatment regimens, and non-toxic approaches for relapsed, refractory, or intolerant patients are lacking. In this review we discuss these challenges and highlight research advances aiming to provide solutions. Unlocking the potential of risk-adapted non-toxic CNS-directed therapy requires; (1) discovery of robust diagnostic, prognostic and response biomarkers for CNS-leukemia, (2) identification of novel therapeutic targets combined with associated investment in drug development and early-phase trials and (3) engineering of immunotherapies to overcome the unique challenges of the CNS microenvironment. Fortunately, research into CNS-ALL is now making progress in addressing these unmet needs: biomarkers, such as CSF-flow cytometry, are now being tested in prospective trials, novel drugs are being tested in Phase I/II trials, and immunotherapies are increasingly available to patients with CNS relapses. The future is hopeful for improved management of the CNS over the next decade.

SOHO State of the Art Updates and Next Questions | Novel Approaches to Pediatric T-cell ALL and T-Lymphoblastic Lymphoma

While outcomes for children with T-cell acute lymphoblastic leukemia (T-ALL) and T-lymphoblastic lymphoma (T-LL) have improved significantly with contemporary therapy, outcomes for patients with relapsed or refractory (r/r) disease remain dismal. Improved risk stratification and the incorporation of novel therapeutics have the potential to improve outcomes further in T-ALL/T-LL by limiting relapse risk and improving salvage rates for those with r/r disease. In this review we will discuss the challenges and new opportunities for improved risk stratification in T-ALL and T-LL. We will further discuss the recent incorporation of the novel therapeutics nelarabine and bortezomib into front-line therapy for children with T-ALL and T-LL. Finally, we will address new classes of targeted small molecule inhibitors, immunotherapeutics, and chimeric antigen receptor T-cell therapies under investigation in r/r T-ALL and T-LL.

The genomic landscape of pediatric acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. Here, using whole-genome, exome and transcriptome sequencing of 2,754 childhood patients with ALL, we find that, despite a generally low mutation burden, ALL cases harbor a median of four putative somatic driver alterations per sample, with 376 putative driver genes identified varying in prevalence across ALL subtypes. Most samples harbor at least one rare gene alteration, including 70 putative cancer driver genes associated with ubiquitination, SUMOylation, noncoding transcripts and other functions. In hyperdiploid B-ALL, chromosomal gains are acquired early and synchronously before ultraviolet-induced mutation. By contrast, ultraviolet-induced mutations precede chromosomal gains in B-ALL cases with intrachromosomal amplification of chromosome 21. We also demonstrate the prognostic significance of genetic alterations within subtypes. Intriguingly, DUX4- and KMT2A-rearranged subtypes separate into CEBPA/FLT3- or NFATC4-expressing subgroups with potential clinical implications. Together, these results deepen understanding of the ALL genomic landscape and associated outcomes.

Rates of laboratory adverse events by course in paediatric leukaemia ascertained with automated electronic health record extraction: a retrospective cohort study from the Children's Oncology Group

BACKGROUND

Adverse events are often misreported in clinical trials, leading to an incomplete understanding of toxicities. We aimed to test automated laboratory adverse event ascertainment and grading (via the ExtractEHR automated package) to assess its scalability and define adverse event rates for children with acute myeloid leukaemia and acute lymphoblastic leukaemia.

METHODS

For this retrospective cohort study from the Children's Oncology Group (COG), we included patients aged 0-22 years treated for acute myeloid leukaemia or acute lymphoblastic leukaemia at Children's Healthcare of Atlanta (Atlanta, GA, USA) from Jan 1, 2010, to Nov 1, 2018, at the Children's Hospital of Philadelphia (Philadelphia, PA, USA) from Jan 1, 2011, to Dec 31, 2014, and at the Texas Children's Hospital (Houston, TX, USA) from Jan 1, 2011, to Dec 31, 2014. The ExtractEHR automated package acquired, cleaned, and graded laboratory data as per Common Terminology Criteria for Adverse Events (CTCAE) version 5 for 22 commonly evaluated grade 3-4 adverse events (fatal events were not evaluated) with numerically based CTCAE definitions. Descriptive statistics tabulated adverse event frequencies. Adverse events ascertained by ExtractEHR were compared to manually reported adverse events for patients enrolled in two COG trials (AAML1031, NCT01371981; AALL0932, NCT02883049). Analyses were restricted to protocol-defined chemotherapy courses (induction I, induction II, intensification I, intensification II, and intensification III for acute myeloid leukaemia; induction, consolidation, interim maintenance, delayed intensification, and maintenance for acute lymphoblastic leukaemia).

FINDINGS

Laboratory adverse event data from 1077 patients (583 from Children's Healthcare of Atlanta, 200 from the Children's Hospital of Philadelphia, and 294 from the Texas Children's Hospital) who underwent 4611 courses (549 for acute myeloid leukaemia and 4062 for acute lymphoblastic leukaemia) were extracted, processed, and graded. Of the 166 patients with acute myeloid leukaemia, 86 (52%) were female, 80 (48%) were male, 96 (58%) were White, and 132 (80%) were non-Hispanic. Of the 911 patients with acute lymphoblastic leukaemia, 406 (45%) were female, 505 (55%) were male, 596 (65%) were White, and 641 (70%) were non-Hispanic. Patients with acute myeloid leukaemia had the most adverse events during induction I and intensification II. Hypokalaemia (one [17%] of six to 75 [48%] of 156 courses) and alanine aminotransferase (ALT) increased (13 [10%] of 134 to 27 [17%] of 156 courses) were the most prevalent non-haematological adverse events in patients with acute myeloid leukaemia, as identified by ExtractEHR. Patients with acute lymphoblastic leukaemia had the greatest number of adverse events during induction and maintenance (eight adverse events with prevalence ≥10%; induction and maintenance: anaemia, platelet count decreased, white blood cell count decreased, neutrophil count decreased, lymphocyte count decreased, ALT increased, and hypocalcaemia; induction: hypokalaemia; maintenance: aspartate aminotransferase [AST] increased and blood bilirubin increased), as identified by ExtractEHR. 187 (85%) of 220 total comparisons in 22 adverse events in four AAML1031 and six AALL0923 courses were substantially higher with ExtractEHR than COG-reported adverse event rates for adverse events with a prevalence of at least 2%.

INTERPRETATION

ExtractEHR is scalable and accurately defines laboratory adverse event rates for paediatric acute leukaemia; moreover, ExtractEHR seems to detect higher rates of laboratory adverse events than those reported in COG trials. These rates can be used for comparisons between therapies and to counsel patients treated on or off trials about the risks of chemotherapy. ExtractEHR-based adverse event ascertainment can improve reporting of laboratory adverse events in clinical trials.

FUNDING

US National Institutes of Health, St Baldrick's Foundation, and Alex's Lemonade Stand Foundation.

A natural history study of nitrous oxide versus propofol-assisted intrathecal therapy in the treatment of acute lymphoblastic leukemia

BACKGROUND

Childhood acute lymphoblastic leukemia (ALL) treatment requires numerous lumbar punctures (LPs) with intrathecal (IT) chemotherapy to prevent and treat central nervous system disease. Historically, LPs in this setting are performed using propofol sedation at most institutions. At our center, LPs are often alternatively performed under nitrous oxide (N₂ O). To date, there have been no large-scale assessments comparing these sedation methods for this purpose.

PROCEDURES

Retrospective cohort study of patients aged 0-31 years with ALL treated between January 1, 2013 and December 31, 2018 at the Children's Minnesota Cancer and Blood Disorders Center, including all therapeutic LPs performed in the clinic setting under either propofol or N₂ O.

RESULTS

Among 215 patients and 2677 therapeutic LPs, 56.6% (n = 1515) occurred under N₂ O, with 43.3% (n = 93) of patients using exclusively N₂ O with all LPs. The incidence of traumatic LPs (red blood cell [RBC] ≥10 cells/μl) was similar between both treatments (27.3% vs. 30.2%). Successful IT chemotherapy delivery (99.7% N₂ O vs. 99.8% propofol) did not differ between sedation types. Experiencing a traumatic LP under N₂ O was associated with a sedation switch for the subsequent LP (adjusted odds ratio [aOR] 2.40, p = .002), whereas older age (aOR 1.08, p < .0001) and higher body mass index (BMI) percentile (aOR 1.01, p = .009) were associated with increased likelihood for undergoing a traumatic LP.

CONCLUSION

N₂ O is an effective sedation option for therapeutic LPs in children with ALL with noninferiority to propofol in terms of IT chemotherapy administration and traumatic LP incidence. For many patients, N₂ O can effectively replace propofol during LP procedures, which has important safety and quality-of-life implications.

Isolated CNS Relapse in 2 High-Risk B-cell Acute Lymphoblastic Leukemia Patients Following SARS-CoV-2 Infection

B-cell acute lymphoblastic leukemia (B-ALL) is the most common pediatric malignancy with a highly favorable overall prognosis. Central nervous system (CNS) relapse of B-ALL is relatively rare and is associated with inferior survival outcomes. We present two patients with B-ALL who developed isolated CNS relapse following confirmed infection with severe acute respiratory syndrome coronavirus 2. In addition to individual and disease factors, we posit that delays in therapy together with immune system modulation because of severe acute respiratory syndrome coronavirus 2 may account for these 2 cases of CNS relapsed B-ALL. We report on this clinical observation to raise awareness of this potential association.

Management of CNS Disease in Pediatric Acute Lymphoblastic Leukemia

PURPOSE OF REVIEW

The treatment of acute lymphoblastic leukemia (ALL) is one of the success stories of pediatric oncology, but challenges and questions remain, including the optimal approach to the treatment of central nervous system (CNS) leukemia. It is unclear why some children with ALL develop CNS leukemia and others do not, and there remains debate regarding optimal regimens for prophylaxis, upfront treatment, and the treatment of CNS relapses. These topics are especially important since both cranial radiation therapy (CRT) and intensive intrathecal therapy carry risks of both short- and long-term adverse effects. In this review, we aim to identify areas of ongoing debate on this topic, review the biology of CNS leukemia, and summarize clinical trial data that address some of these questions.

RECENT FINDINGS

Both retrospective and meta-analyses have demonstrated that few patients with ALL benefit from CRT as a component of CNS-directed treatment for de novo disease, allowing cooperative groups to greatly limit the number of patients undergoing CRT as part of their initial ALL regimens. More recent efforts are focusing on how best to assay for low levels of CNS disease at the time of diagnosis, as well as the biological drivers that may result in CNS leukemia in certain patients. Progress remains to be made in the identification and treatment of CNS leukemia in pediatric ALL. Advancements have occurred to limit the number of children undergoing CRT, but much has yet to be learned to better understand the biology of and risk factors for CNS leukemia, and novel approaches are required to approach CNS relapse of ALL.