National Cancer Institute High Risk Research Articles

Hepatic Dysfunction during Induction Chemotherapy in Children with Acute Lymphoblastic Leukemia and Lymphoblastic Lymphoma and Its Effects on Subsequent Therapy and Outcome

Abstract Introduction The overall survival rate for childhood acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL) has shown tremendous growth in the recent years. Hepatic dysfunction is one of the complications seen during therapy and can add to the underlying morbidity of the disease, delay in chemotherapy, modification of drugs, and rarely fulminant hepatic failure. Objective This article aims to find out the prevalence of hepatic dysfunction during induction chemotherapy for ALL and LBL. Materials and Methods This was a retrospective study, where the data of all children between 1 and 18 years of age with ALL and LBL treated at our center as per the UK-ALL 2003 protocol between December 2013 and December 2021 have been included from the medical records. Hepatic dysfunction was defined as grade 3 and 4 alanine transaminase (ALT) and aspartate transaminase (AST) levels as per Common Terminology Criteria for Adverse Events v5.0 and hyperbilirubinemia as ≥ 1.4 mg/dL as the chemotherapy modification begins at this cutoff. Data from children with hepatic dysfunction was compared with those without hepatic dysfunction using chi-squared test and Student's t-tests. Those variables with a p-value of < 0.2 were analyzed with multivariate regression analysis. Kaplan–Meier survival estimates were used to calculate the event-free survival (EFS). Results A total of 142 children were included in the study. Thirty-one (21.8%) children developed hepatic dysfunction, 14 (9.9%) of them with ALT/AST elevation and 27 (19%) with bilirubin elevation. Weight (mean 25 ± 13.5, p 0.01), body surface area (mean 0.87 ± 0.29, p 0.02), and National Cancer Institute high risk (p 0.005) were associated with hepatic dysfunction in univariate analysis but none of them were significant in multivariate regression analysis. Treatment modification was required in 14/31 children with hepatic dysfunction. Death in induction was more among children with hepatic dysfunction (p < 0.001). There was no significant impact on minimal residual disease outcomes. Five-year EFS (death or relapse) was 59.93 ± 9% in children with hepatic dysfunction as opposed to 72 ± 5.0% in those without hepatic dysfunction (95% confidence interval, p = 0.07). Conclusion One in five children with ALL and LBL on induction therapy developed hepatic dysfunction. Almost half of those with hepatic dysfunction required chemotherapy modifications.

Asparaginase-Associated Toxicities and Hypersensitivity Reactions in Pediatric and Adolescent Down Syndrome Patients with Acute Lymphoblastic Leukemia or Lymphoma

Children with Down syndrome acute lymphoblastic leukemia (DS-ALL) have worse prognosis compared to those with non-DS-ALL, largely due to higher treatment related mortality. Pegaspargase (PEG) is integral in protocols for the treatment of pediatric ALL and lymphoblastic lymphoma (LBL), and full exposure to all doses of PEG can be limited by toxicities, including hypersensitivity reactions (HSR) due to the production of anti-asparaginase antibodies rendering PEG therapy ineffective. To date, minimal data has been reported on the use of PEG in children with DS-ALL/LBL. We conducted a prospective, multicenter study to evaluate the efficacy of premedicating pediatric and adolescent ALL/LBL patients receiving PEG with antihistamines-H1 and -H2 blockers with subsequent therapeutic drug monitoring (TDM) to better identify patients with true HSR versus those with non-antibody mediated infusion reactions. Here, we report on the incidence of HSRs and PEG-associated toxicities in the cohort of children with DS-ALL/LBL. Eligible patients from six centers received PEG, as per a Children's Oncology Group protocol, beginning in induction therapy. An H1 blocker (diphenhydramine) and H2 blocker (ranitidine, famotidine or cimetidine) were administered prior to PEG administration in consolidation and subsequent cycles. TDM was performed at 7 and 14 days post each PEG. PEG was administered at 2500 International units/m 2/dose that was capped for obesity or age > 22 years. Patients were monitored for HSR and other PEG-related toxicities using CTCAE version 5 criteria. Therapeutic asparaginase activity (AA) was defined as ≥ 0.1 IU/mL (≥100 IU/L) at 7 days post infusion and greater than the lower level of quantification at 14 days. We observed for silent inactivation (subtherapeutic levels without symptoms) and accelerated clearance (levels below quantification at 14 days without symptoms). Descriptive statistics summarized patient characteristics and mixed effects modeling procedure assessed mean AA levels at 7 and 14 days with specification of repeat measures and compound symmetry covariance structure. Out of 148 patients, 9 DS (8 B-ALL, 1 B-LBL) were enrolled between 10/2019 - 3/2022. The median age at diagnosis was 5.0 years [IQR: 4.3, 14.9], 4 were National Cancer Institute (NCI) High Risk (HR) at diagnosis, 4 were Hispanic and none were obese. ALL 9 DS patients received a total of 26 doses of PEG at the standard dose without dose capping required. The mean unadjusted AA levels at 7 and 14 days post PEG were 0.76 IU/ml (SE=0.11) and 0.54 IU/ml (SE=0.11), respectively, p<.001. None of the DS patients experienced HSR or silent inactivation. Accelerated clearance was observed in 1 patient. Nineteen episodes of grade >3 PEG-associated toxicity were observed in 5 DS-ALL patients (5/9; 55.6%). PEG-associated toxicity was observed more frequently in older patients whose mean age was 13 years (SD=6.2) versus 4.3 years in those without toxicity (SDE=0.9), p=.028. Four of the DS-ALL who experienced toxicities were NCI HR at diagnosis and > 10 years of age. For the 19 episodes of toxicities: 6 occurred during induction, 9 during consolidation, and 4 during delayed intensification. The most common toxicity observed was hepatoxicity (increased alanine transaminase) which was experienced by 3 DS-ALL patients. There were no grade > 3 hyperbilirubinemia. All 4 DS-ALL patients who experienced PEG toxicity during induction also had toxicity with subsequent cycles. One DS-ALL patient had a dose limiting toxicity (grade 3 pancreatic pseudocyst), requiring discontinuation of subsequent PEG therapy. There were no grade 4 or 5 toxicities observed. All 4 DS patients who did not experience toxicities were NCI Standard Risk patients. All DS patients had undetectable minimal residual disease (MRD) that was < 0.01 at the end of induction therapy. We noted that in this small DS-ALL/LBL cohort, none of the patients experienced HSR, and all achieved therapeutic AA at both time points of 7 and 10 days post PEG. Five (55.6%) of the DS-ALL patients experienced at least one grade > 3 asparaginase toxicity, and they were older than those without toxicity. Most toxicity occurred during the consolidation phase and no grade 4 or 5 toxicities were observed. Given the PEG-associated toxicity observed in DS ALL/LBL, we are conducting pharmacokinetic analysis to propose a lower dose of PEG which may minimize toxicity while maintaining therapeutic efficacy.

Impact of minimal residual disease on relapse in childhood acute lymphoblastic leukemia: Lessons learnt from a tertiary cancer center in India

Prognostic predictive value of end of induction minimal residual disease (EOI-MRD) is well established in acute lymphoblastic leukemia (ALL). We evaluated the factors likely to affect EOI-MRD positivity (>0.01%) by flow cytometry and relapse in different BFM-95 (Berlin–Frankfurt–Munich) risk groups among children and adolescents. In this retrospective study, data of 223 newly diagnosed patients with ALL was analyzed. Association between demographic and pretreatment characteristics with EOI-MRD was assessed. Risk factors for relapse were analyzed using univariate and multivariate Cox regression. Proportion of the SR (standard risk), MR (moderate risk), and HR (high risk) patients was 18.8%, 60.9%, 20.3%, respectively. Positive EOI-MRD among these risk groups was observed in 11.9%, 18.3%, and 55.5% patients respectively (p value <.01%). MRD positivity was more likely to be associated with older age (>10 years) and BFM-HR patients (p value .0008 and <.0001). Thirty-four (15.2%) patients relapsed in the whole cohort. On univariate analysis, statistically significant factors for RFS (relapse-free survival) included hyperleukocytosis, high-risk cytogenetics, NCI (National Cancer Institute) high risk, poor day-8 prednisolone response, BFM–HR and positive EOI-MRD status. Of all these only EOI-MRD retained its impact by multivariate analysis. Positive EOI-MRD significantly predicted relapse in BFM-MR with 5-year RFS of 88.0% and 68.4% (p value .02). Five-year RFS of EOI-MRD negative and positive groups were 86.4% and 65.5%, respectively (p value .004). EOI-MRD is a powerful tool to predict relapse in children and adolescent with ALL especially in BFM-MR. Application of MRD in HR patients needs to be redefined in conjunction with other variables.

Prognostic significance of CD45 antigen expression in pediatric acute lymphoblastic leukemia

ObjectivesThe treatment of pediatric acute lymphoblastic leukemias (ALL) has seen remarkable advances recently. However, relapse occurs in approximately 20% of cases which necessitates identifying additional high risk parameters for treatment intensification. The aim of this study is to assess the prognostic significance of CD45 antigen expression in pediatric ALL. MethodsWe studied 363 pediatric patients with B cell precursor-ALL (BCP-ALL) (n = 313) and T-ALL (n = 50). The ratio of median fluorescence intensity of CD45 expressed in leukemic blasts and normal lymphocytes was calculated. The 75th percentile was taken as cut-off to categorise patients into CD45 high and CD45 low groups. ResultsThe 75th percentile was 0.141 in BCP-ALL and 0.548 in T-ALL. In BCP-ALL, there was a statistically significant association of age (≥10 years) (p = 0.027) and National Cancer Institute high risk group (p = 0.001) with high CD45 expression but not in T-ALL. Worse event-free survival (EFS) was seen with high CD45 expression in BCP-ALL (42.17% versus 60.83%, p = 0.0053). In T-ALL, there was no association between CD45 expression and EFS (CD45 high 40.40% versus low 67.35%, p = 0.414). The overall survival (OS) was 70% versus 60% (p = 0.38) in BCP-ALL and the OS was 82% versus 68% (p = 0.16) in T-ALL for CD45 low versus CD45 high groups, respectively. ConclusionWe conclude that high CD45 surface expression is associated with worse EFS in pediatric BCP-ALL.

Enhanced Risk Stratification of 21,178 Children, Adolescents, and Young Adults with Acute Lymphoblastic Leukemia (ALL) Incorporating White Blood Count (WBC), Age, and Minimal Residual Disease (MRD) at Day 8 and 29 As Continuous Variables: A Children's Oncology Group (COG) Report

Current risk stratification for COG ALL patients (pts) relies on National Cancer Institute (NCI) risk group (RG) at diagnosis, somatic genetics, and early response to therapy as measured by specific thresholds of minimal residual disease (MRD) using flow cytometry on day 8 peripheral blood (D8 PB) and day 29 bone marrow (D29 BM). NCI RG is defined as age 1-10 years (yrs) and white blood cell count (WBC) &amp;lt;50,000/uL (Standard Risk, SR); all other non-infant patients are high risk (HR). Using COG risk stratification, current therapies for SR and HR patients are based on 5-year projected event-free survival (EFS) of 92-97%, and 65-86%. Currently, two subsets, Ph-like and very high risk (VHR) ALL are identified with additional assays-genomic sequencing for Ph-like, and persistent BM MRD on D29 and at end of consolidation for VHR, and are eligible for different treatments. However, as UK investigators recently published (O'Connor, JCO 2018; Enshaei, Blood 2020), using multiple continuous variables as threshold-defined categorical data may diminish the power of accurately predicting relapse, and thus prescribe inappropriate post induction therapy. We tested the UK approach of transforming categorical variables into continuous data on 13,870 NCI SR and 7308 NCI HR B-ALL pts treated on two generations of COG trials: AALL0331 (SR; n=5094), AALL0932 (SR; n=8776), AALL0232 (HR; n=2883), and AALL1131 (HR; n=4425). Down syndrome and Ph+ pts were excluded from analysis. Clinical characteristics are listed in Table 1. ETV6-RUNX1 (25.24%) and double trisomies of chromosome 4, 10 (DT) (23.77%) comprised the favorable risk genetic RG (FRG) group (48.15% of risk classified) while KTM2A rearranged (1.71%), hypodiploidy (1.67%), and iAMP21 (2.56%) comprised the unfavorable risk genetic RG (URG) (6.26%). All others with genetic information were classified as intermediate risk genetic RG (IRG) (45.59% of risk classified). Among 4873 pts tested, 20.46% had Ph-like ALL. D8 PB and D29 BM MRD data were available for 76.42% and 96.69% pts, respectively. We first log transformed WBC, D8 and D29 MRD and displayed these by treatment protocol, NCI RG, and FRG/URG (separating out Ph-like independently). Age and WBC followed the normal expected distribution with the median age of SR pts 4.0 yrs (range 1-9) and HR 12 yrs (range 1-30). Transformed MRD was displayed as a variable t(MRD), corresponding to the negative log; max t(D29 MRD) was 13.82, corresponding to MRD &amp;lt;1.0 x 10-5.The great majority of pts were MRD-positive at D8 (mean t(D8 MRD) 7.42); but there was broad distribution of values, with NCI SR and FRG pts having lower t(D8 MRD) (mean 7.52 and 8.08) than NCI HR and URG pts (mean 7.20 and 6.56) (p &amp;lt; 0.001) . The great majority of pts were D29 MRD-negative (mean t(D29 MRD) 12.08), with NCI SR and FRG pts achieving lower D29 MRD (mean t(D29 MRD) 12.43 and 12.73) than NCI HR and URG pts (mean 11.40 and 10.95) (p&amp;lt; 0.0001). Ph-like ALL pts had a mean t(D8 MRD) and t(D29 MRD) of 6.22 and 9.37. We next conducted a univariate analysis for risk factors for relapse, including sex, age, WBClog, CNS status, protocol-defined rapid early response status, FRG, URG, t(D8 MRD), and t(D29 MRD); all variables except CNS status were significant p &amp;lt; 0.0001). Multivariable modeling showed that WBClog, FRG, URG, t(D8 MRD), t(D29 MRD) retained significance (p &amp;lt; 0.0001). Finally, we applied the UK Prognostic Index (PIUKALL) equation [t(d29 MRD) x -0.218 + CYTO-GR x -0.440 + CYTO-HR x 1.066 + WBClog x 0.138] to the COG data using protocol, NCI RG, FRG, URG, IRG, or Ph-like RG in the model and validated the trends for relapse-free survival (RFS), which were similar in our groups with an overall median PIUKALL of -2.63 (mean -2.32, SD -.90, min -3.54, max 1.79). We next added in t(D8 MRD) to define a PICOG and determined that D8 PB MRD added significantly to the model, mostly through discriminating between the hazard ratios of the FRG and the URG RGs. Importantly, the D8 PB MRD led to a qualitatively more distinctive group with a potentially lower predicted RFS in NCI SR pts, a group that has been more difficult to predict in the past, and yet comprises nearly half of all relapse events. Our analyses of 21,178 COG B-ALL pts confirm and extend the utility of integrating WBC and MRD as continuous rather than categorical values to refine risk stratification for patient treatment and trial design. Disclosures Loh: Pfizer: Other: Institutional Research Funding; Medisix Therapeutics: Membership on an entity's Board of Directors or advisory committees. Borowitz:Amgen: Honoraria. Zweidler-McKay:ImmunoGen, Inc.: Current Employment. Mattano:Melinta Therapeutics: Consultancy; Novartis: Consultancy; Pfizer: Consultancy. Hunger:Amgen: Current equity holder in publicly-traded company, Honoraria; Novartis: Consultancy. Raetz:Celgene/BMS: Other; Pfizer: Research Funding. Mullighan:Illumina: Consultancy, Honoraria, Speakers Bureau; Pfizer: Honoraria, Research Funding, Speakers Bureau; AbbVie, Inc.: Research Funding.

Outcomes of Patients with Down Syndrome and CRLF2-Overexpressing Acute Lymphoblastic Leukemia (ALL): A Report from the Children's Oncology Group (COG)

Background: Patients with Down syndrome (DS) have an approximately 10-fold increased risk of developing ALL, and the spectrum of genetic alterations differs from that of non-DS ALL. Rearrangement and/or overexpression of cytokine receptor-like factor 2 (CRLF2+) occurs in 50% of DS ALL, compared to only 5-10% CRLF2+ cases in non-DS children and adolescents. JAK2 or JAK1 mutations co-occur in about half of CRLF2+ cases in both DS and non-DS ALL. The prognostic significance of CRLF2+ ALL also appears to differ in the limited data reported to date, with less adverse impact in patients with DS compared to non-DS ALL. Here, we report the clinical characteristics and prognostic significance of B-ALL with CRLF2 overexpression and JAK alterations in children and adolescents/young adults (AYA) with DS who were treated on Children's Oncology Group (COG) clinical trials from 2003-2016. Methods: We analyzed clinical, laboratory, and outcome data for 317 patients with DS B-ALL treated on standard risk (SR) trials AALL0331 and AALL0932 and high risk (HR) trials AALL0232 and AALL1131, for whom CRLF2 status and rearrangement partners (IGH or P2RY8) were ascertained by flow cytometric assessment of surface expression; fluorescence in situ hybridization; and/or polymerase chain reaction (PCR) testing. JAK mutations were ascertained in a subset by PCR and sequencing. Minimal residual disease (MRD) was assessed by flow cytometry at the end of induction (EOI) and at end of consolidation (EOC) for a subset of EOI MRD+ patients. Results: We identified 168/317 (53.0%) CRLF2+ cases, and among those assessed for CRLF2 partner, 17/73 (23.3%) were IGH-CRLF2 and 56/73 (76.7%) were P2RY8-CRLF2. In the subset of 165 cases tested for JAK mutations (85 CRLF2- and 80 CRLF2+), 42/165 (25.4%) had JAK mutations, all of which co-occurred in CRLF2+ cases. CRLF2 positivity was significantly associated with younger age at diagnosis: 140/168 (83.3%) of CRLF2+ cases were under 10 years old, versus 106/149 (71.1%) of CRLF2- cases, p&amp;lt;0.01. P2RY8-CRLF2 cases were significantly more likely than IGH-CRLF2 cases to be associated with age under 10 years at diagnosis (92.9% vs 29.4%, p&amp;lt;0.0001), initial white blood count (WBC) &amp;lt;50x103 (80.4% vs 52.9%, p&amp;lt;0.024), National Cancer Institute (NCI) standard risk status (73.2% vs 23.5%, p&amp;lt;0.0002), and day 29 MRD &amp;lt;0.01% (67.9% vs 37.5%, p&amp;lt;0.028). There were no significant associations between JAK mutation status and any clinical features assessed (sex, initial WBC, central nervous system or testicular involvement, NCI risk group, or EOI/EOC MRD). Among patients with neutral cytogenetics (defined as neither favorable [ETV6-RUNX1, double trisomies of chromosomes 4 and 10] nor unfavorable [BCR-ABL1, KMT2A-rearranged, hypodiploid, iAMP21]), survival did not significantly differ between CRLF2+ and CRLF2- patients (Figure 1A,B), either for 5-year event-free survival (EFS) (79.1 +3.6% vs 77.6 +4.7%, p=0.856) or 5-year overall survival (OS) (89.5 ±2.8% vs 84.9 ±4.1%, p=0.674). There were also no significant differences in EFS or OS based on JAK mutation status or CRLF2 partner, although there were trends toward poorer outcomes in the CRLF2+/JAK+ and IGH-CRLF2 subgroups (Figure 1C). Finally, there was no significant difference in 5-year cumulative incidence of relapse (CIR) according to CRLF2 status (CRLF2+ 16.0 +3.0%, CRLF2- 10.6 +2.6%, p=0.179), although there were non-significant trends toward more relapses in CRLF2+ cases overall and in the NCI HR subgroup analysis. Discussion: Whereas CRLF2 and JAK alterations are associated with higher MRD, poorer survival, and increased CIR in patients with high-risk ALL without DS, these alterations do not demonstrate strong adverse prognostic impact in children and AYAs with DS-ALL treated on recent frontline COG trials, although larger sample sizes are needed to adequately assess for possible poorer prognoses associated with the CRLF2+/JAK+ and IGH-CRLF2 subgroups. Regardless, given the frequency of these targetable lesions and the increased risk of relapse and chemotherapy-associated toxicities in patients with DS-ALL, targeted therapies currently under investigation for these genetic lesions may be beneficial to replace some intensive blocks of therapy in DS-ALL with CRLF2 and/or JAK alterations, both to enhance anti-leukemic efficacy and decrease intensive chemotherapy-associated toxicities. Figure 1 Disclosures Tasian: Gilead Sciences: Research Funding; Incyte Corporation: Research Funding; Aleta Biotherapeutics: Membership on an entity's Board of Directors or advisory committees. Borowitz:Amgen: Honoraria. Mullighan:Illumina: Consultancy, Honoraria, Speakers Bureau; AbbVie, Inc.: Research Funding; Pfizer: Honoraria, Research Funding, Speakers Bureau. Raetz:Celgene: Other: DSMB member; Pfizer: Other: Institutional research funding. Loh:Pfizer: Other: Institutional Research Funding; Medisix Therapeutics: Membership on an entity's Board of Directors or advisory committees. Hunger:Novartis: Consultancy; Amgen: Current equity holder in publicly-traded company, Honoraria.

Outcomes and impact of minimal residual disease (MRD) in pediatric, adolescent and young adults (AYA) with acute lymphoblastic leukemia treated with modified MCP 841 protocol

Background: The impact of minimal residual disease (MRD) on overall survival (OS) is insufficiently studied in pediatric, adolescent, and young adults (AYA) with acute lymphoblastic leukemia (ALL) treated with modified MCP 841 protocol. Objectives: We planned to evaluate the outcomes (post-induction response rates, MRD, and OS) with modified MCP 841 in pediatric and AYA ALL. Materials and Methods: This was a retrospective audit of patients with ALL registered between March 01, 2017, and August 31, 2019. Patients who received at least 7 days of therapy on modified MCP 841 protocol were analyzed. Response evaluation was done on day 35 of induction with bone marrow aspiration, and MRD was assessed with flow cytometry with Results: 130/167 (78%) patients were started on MCP 841 protocol; the remaining 37 (22%) patients defaulted after the first visit. B-cell ALL was more common at 78 (60%). 94 (72%) had National Cancer Institute High Risk. Day 8 good prednisolone response (GPR) was seen in 76 (58%) patients. Morphological remission was noted in 90/107 (84%) patients. MRD status was available in 84 (78%) patients. 46 (43%) patients achieved MRD-negative status. The median follow-up was 21 months (range, 10–31 months). The median OS was 30 months (95% CI, 15.5–42.8 months). One-year and 2-year survival was 87% and 60%, respectively. Patients who were MRD negative did better than those with MRD positive, 29 versus 22 months (P = 0.03). GPR performed better than those with Poor Prednisolone Response (PPR), 29 versus 15 months (P = 0.01). Conclusion: Post-induction MRD is a useful prognostic tool for ALL patients treated with modified MCP 841 protocol. Outcomes are suboptimal compared to those reported from the developed western world.

Improved Treatment of Childhood ALL in Malaysia

The survival rate of childhood acute lymphoblastic leukemia (ALL) has reached &gt;80-90% in developed countries, which is a triumph of modern medicine. This success is due to implementation of contemporary treatment protocols, optimal application of risk stratification, risk-directed multi-agent chemotherapy regimens, and improved supportive care. Unfortunately, such improvements have not translated to Low Middle Income Countries (LMICs), where 90% of the world's children live. The estimated 5 year survival rates in Asia range widely between 44.3% and 80%. The Intercontinental-BFM2002 study, conducted in 15 upper-middle and high-income countries reported a 5 year event-free survival (EFS) and overall survival (OS) rates of 74% and 82%, respectively. Factors that may contribute to the lower survival in LMICs are highly complex, including delays in presentation, diagnostic inaccuracy, restricted budget for risk-stratification and appropriate treatment, treatment abandonment and socio economic status. In Malaysia, different protocols are used by different leukemia treatment centers for treating children with ALL. In UKM Medical Centre (UKMMC), the UKALL protocols (modified UK X, XI, XII, 97(99) and 2003) have been used in the Pediatric Hemato-Oncology Unit since the 1990s. Herein, we report the adopted protocol, the stratification profile and outcome of children with ALL, treated with modified UKALL 97(99) and UKALL 2003 in our institution from 2006 to 2014. Clinical data from children with ALL, who received these modified therapies, were retrospectively reviewed. Prednisolone was used in modified UKALL97(99) and Dexamethasone in modified UKALL 2003, while 6-mercaptopurine was used in both modified protocols. Otherwise, chemotherapy and duration of treatment were identical to the original protocols of Regimens A, B and C. ALL was diagnosed based on standard morphology and immunophenotyping criteria. At diagnosis, patients were stratified according to the National Cancer Institute (NCI) risk criteria and using FISH for detection of cytogenetic abnormalities. EFS and OS were determined using the Kaplan-Meier methods. Newly diagnosed ALL in 156 children were included in the study; 103 (66.0%) were standard risk, 49 (31.4%) were high risk and 4 (2.5%) were infants. There were 2 children with Down syndrome. The success rate of FISH was 76.4% (94/123). Patients were stratified as standard risk, based on ETV6-RUNX1, and high risk based on unfavorable cytogenetics, BCR-ABL and MLL rearrangements. Half of the patients with unfavorable cytogenetics were classified in the NCI high risk group, with WCC &gt;100x109/L. A total of 151 patients were treated as per risk stratification, 2 patients transferred care, while 3 patients refused treatment. Mortality from sepsis during treatment was approximately 10%, including 2 deaths during induction remission and induction at relapse. The majority of disease progression was relapse-related, however, treatment abandonment also contributed to relapse. Approximately 5% of patients abandoned their treatment (3 patients abandoned and 3 patients refused treatment). The 5-year OS for the standard risk group was 86.6%, with 3-year and 5-year EFS of 88.1% and 83.4%, respectively. The 5-year OS for the high risk group was 65.7%, while 3-year and 5-year EFS were 64.7% and 58.2%, respectively (Figure 1). The MRC UKALL97 stratification by NCI risk reported a 5-year EFS of 83.1% for the standard risk group and 66.9% for the high risk group, while the UKALL2003 interim analysis reported a 5-year EFS of 87.7%. The MRC UKALL97/99 reported a 5-year OS of 88%. The cure rate of children with standard risk ALL at UKMMC, using modified UKALL 97(99) and UKALL 2003 protocols, was comparable to MRC UKALL97. However, the cure rate for high risk ALL was comparatively lower. This single center study from UKMMC has highlighted some critical factors that improved the outcome of children with ALL and suggests further improvements that are necessary to reduce the relapse rate, especially in the high risk ALL patients. Disclosures No relevant conflicts of interest to declare.

Cyclin dependent kinase inhibitor 2A/B gene deletions are markers of poor prognosis in Indian children with acute lymphoblastic leukemia.

Cyclin dependent kinase inhibitor 2A/B (CDKN2A/B) genes are implicated in many malignancies including acute lymphoblastic leukemia (ALL). These tumor suppressor genes, with a key regulatory role in cell cycle are located on chromosome 9p21.3. Previous studies involving CDKN2A/B gene deletions have shown mixed associations with survival outcome in childhood ALL. Hundred and four newly diagnosed children with ALL (1-14 years) were enrolled in this study. Genomic DNA from pretreatment bone marrow/peripheral blood samples of these children was investigated for copy number alterations in CDKN2A/B genes using multiplex ligation dependent probe amplification assay. Immunophenotype subtyping and cytogenetic and molecular analysis of ALL was performed at start of induction chemotherapy in all children. Children were monitored for response to prednisolone (Day 8), complete morphological remission, and minimal residual disease at the end of induction. The minimum postinduction follow-up period was 6 months. CDKN2A/B deletions were seen in 19.8% (18/91) of B lineage acute lymphoblastic leukemia (B-ALL) and 38.5% (5/13) of T lineage acute lymphoblastic leukemia (T-ALL). Monoallelic CDKN2A/B deletions were found in 61.1% of total deletions in B-ALL while all the children with T-ALL harbored biallelic deletions. The prevalence of CDKN2A/B gene deletions was found to be significantly higher in older children (P=0.002), in those with higher leukocyte count (P=0.037), and in National Cancer Institute high risk group patients (P=0.001) in the B-ALL subgroup. Hazard ratio was significantly high for children with CDKN2A/B deletions in total cohort (P=0.004). Children with CDKN2A/B deletion had significantly lesser event free survival (P=0.03). CDKN2A/B deletions were significantly more prevalent in T-ALL subgroup and were found to have higher hazard ratio and lesser event free survival in total cohort in our study.

Characterization of pediatric Philadelphia-negative B-cell precursor acute lymphoblastic leukemia with kinase fusions in Japan.

Recent studies revealed that a substantial proportion of patients with high-risk B-cell precursor acute lymphoblastic leukemia (BCP-ALL) harbor fusions involving tyrosine kinase and cytokine receptors, such as ABL1, PDGFRB, JAK2 and CRLF2, which are targeted by tyrosine kinase inhibitors (TKIs). In the present study, transcriptome analysis or multiplex reverse transcriptase–PCR analysis of 373 BCP-ALL patients without recurrent genetic abnormalities identified 29 patients with kinase fusions. Clinically, male predominance (male/female: 22/7), older age at onset (mean age at onset: 8.8 years) and a high white blood cell count at diagnosis (mean: 94 200/μl) reflected the predominance of National Cancer Institute high-risk (NCI-HR) patients (NCI-standard risk/HR: 8/21). Genetic analysis identified three patients with ABL1 rearrangements, eight with PDGFRB rearrangements, two with JAK2 rearrangements, three with IgH-EPOR and one with NCOR1-LYN. Of the 14 patients with CRLF2 rearrangements, two harbored IgH-EPOR and PDGFRB rearrangements. IKZF1 deletion was present in 16 of the 22 patients. The 5-year event-free and overall survival rates were 48.6±9.7% and 73.5±8.6%, respectively. The outcome was not satisfactory without sophisticated minimal residual disease-based stratification. Furthermore, the efficacy of TKIs combined with conventional chemotherapy without allogeneic hematopoietic stem cell transplantation in this cohort should be determined.

Augmented Consolidation Therapy Based on Minimal Residual Disease (MRD) and Analysis of the Measurement of Sequential MRD in Childhood Acute Lymphoblastic Leukemia : Children's Cancer and Leukemia Study Group of JAPAN (CCLSG), Cclsg ALL 2004 Protocol Study

BACKGROUND: Minimal residual disease (MRD) level after induction (Time Point1:TP1) and before consolidation therapy (Time Point2:TP2) has a strong impact in prediction of outcome for childhood acute lymphoblastic leukemia and it has clinical utility of a prognostic factor to stratify the risk groups in many current studies. We measured MRD levels on various time points to evaluate their prognostic significance in MRD-based augmented therapy.PATIENTS & METHODS: From June 2004 to September 2009, we prospectively assigned 333 consecutive children with ALL, 1〜19 years of age, to receive one of three treatment protocols on the stratification based on National Cancer Institute (NCI) risk criteria. NCI standard risk:SR, NCI high risk:HR and those with a white blood cell count≧1000x109 per L was defined as high-high risk:HHR. Patients were stratified again at TP2, patients with MRD level over 10-3 were assigned to salvage arm, treated in augmented therapy. Among 333 patients, 326 were eligible and 245 were MRD quantifiable. Then, we re-evaluated those samples by RQ-PCR according to the guideline of Euro MRD. Finally 167 cases were analyzed at 7 time points of MRD quantification in the CCLSG ALL2004 study.RESULTS: The overall 5-year event free survival (5-EFS) rate for ALL2004 was 82.5±2.1% (n=326), and 5-EFS of SR group (n=267), HR group (n=86) and HHR group (n=33) were 84.8±2.5%, 80.1±4.3% and 74.7±7.8%, respectively. In the SR group, 5-EFS of standard therapy group (n=124) with TP2 MRD<10-3 was 87.5±3.0% and augmented therapy group's 5-EFS was 80.0±10.3% (n=15, p=0.6124). In the HR group, 5-EFS of standard therapy was 83.1±5.1% (n=54) and augmented therapy group's was 57.1±18.7% (n=7, p=0.870). In the HHR group, 5-EFS of standard therapy was 87.5±8.3% (n=16) and augmented therapy group's was 51.4±20.4% (n=7, p=0.054).TP1, at week 7, at the end of induction, 5-year relapse free survival (5-RFS) was 87.4.% in MRD negative cases (n=115) and 58.3% in MRD positive cases (n=36), and the differences were significant. TP2,week13, during consolidation, and TP3, at week 19 or 22, and at TP4, at week 26 to 28, had significant difference on 5-RFS with cut off of both 10-3 and 10-4. TP7, at the end of therapy, 2 patients were MRD positive and were thought molecular relapse. Additionally, we investigated changes in MRD levels of relapsed cases (n=35). MRD remained cases (n=4), MRD late disappeared cases (n=4), and MRD converted to positivity cases (n=4) were observed.CONCLUSIONS: The impact of predictive power of PCR MRD at TP1 and TP2 was validated, still more TP3 and TP4 were also statistically significant in CCLSG ALL2004 study. Even the patients whose final MRD level was negative could relapse, it is needed to investigate other prognostic factor except MRD. DisclosuresImai:Juno Therapeutics: Patents & Royalties.

Absolute Lymphocyte Count Recovery Independently Predicts Outcome in Childhood Acute Lymphoblastic Leukemia: Experience From a Tertiary Care Cancer Center of a Developing Country.

Accurate risk stratification is essential for successful treatment outcome in childhood acute lymphoblastic leukemia. Early recovery of absolute lymphocyte count (ALC) during induction therapy is emerging as a reliable favorable prognostic indicator that may hold its relevance in resource-constraint settings. This is a retrospective chart review of medical records of 212 patients of acute lymphoblastic leukemia, aged less than 18 years, treated between January 1996 and December 2009. Time to lymphocyte recovery was analyzed with respect to various prognostic factors and survival and Martingale residuals were used to define ALC cut-offs. High-risk disease characteristics including older age (10 y and older), National Cancer Institute high risk, and central nervous system disease at diagnosis were associated with delayed lymphocyte recovery. The 5-year event-free, relapse-free, and overall survival of patients with day 15 ALC of ≥ 500 cells/µL and day 29 ALC of ≥ 1000 cells/µL was 81.7% ± 4%, 86.4% ± 2.8%, 91.0% ± 3%, respectively, compared with those with delayed recovery (16.6% ± 5.6%, 19.3% ± 6.4%, 32.8% ± 7.2%, P < 0.001). In multivariate analysis both these ALC cut-offs retained their significance as prognostic variables of survival. Our analysis revealed ALC to be an important independent predictor of treatment outcome and may provide key prognostic information in settings where minimal residual disease-based risk stratification is not feasible.

Treatment Intensification Improves Outcome in Children with iAMP21 positive ALL

AbstractAbstract ▪656▪This icon denotes a clinically relevant abstractChromosomal abnormalities present in the bone marrow cells of children with acute lymphoblastic leukaemia (ALL) are used to assist diagnosis and define risk groups that guide therapy. One such primary genetic aberration is intrachromosomal amplification of chromosome 21 (iAMP21) which is defined as the presence of 3 or more extra copies of the RUNX1 gene on a single abnormal chromosome 21. FISH with probes targeting the RUNX1 gene is the commonly used detection method. Approximately 2–3% children with ALL harbour iAMP21 and it is associated with older age (median 10 years) and a low white cell count (WCC, <20×109/L).Among 28 patients treated on the MRC ALL97 trial between 1997 and 2002, 27 (96%) achieved a complete remission (CR), 22 (81%) relapsed and 13 (46%) died. The event free survival (EFS), relapse rate (RR) and overall survival (OS) rates at 5 years were 29% (14–46%), 70% (53–86%) and 67% (47–82%), respectively. There was no evidence that National Cancer Institute (NCI) high risk (HR) and standard risk (SR) patients had differential outcomes and the RR appeared constant with time (figure). On the basis of this increased risk of relapse, we chose to stratify these patients to the most intensive arm of the ALL2003 protocol (regimen C) which included augmented Berlin-Frankfurt-Munster (BFM) consolidation, two blocks of escalating Capizzi maintenance and a double delayed intensification. First remission transplants were recommended for patients who were slow early responders (SER) or minimal residual disease (MRD) positive (>0.01%) at day 29. Due to a relatively high transplant related mortality, transplants were restricted to patients not in CR by day 29 after June 2008.Prospective FISH screening of 2575 patients treated on ALL2003 between January 2003 and July 2011 identified 53 (2%) with iAMP21. The cohort showed a female predominance (30:23), had a median age of 10 years and 47 (89%) patients had a WCC <20×109/L. Follow-up information was available for 52 (98%) patients with a median follow-up time of 4.9 years. The majority of patients (48/52, 92%) were transferred to regimen C as directed by the protocol. At least 2 of the remaining 4 patients did not transfer to regimen C because of induction toxicity problems. Treatment response was measured at day 15 or day 8 according to whether patients received a 3 (NCI SR) or 4 (NCI HR) drug induction, respectively. Whilst none of the SR patients were SER, 13/28 (46%) HR patients had >25% blasts at day 8. MRD was assessed in 45 patients: 23 (51%) were positive (>0.01%) and 22 (49%) were negative (<0.01%) at day 28. All patients achieved a CR, 6 (12%) have subsequently relapsed whilst 4 (8%) died in first remission following a transplant from infection (n=3) or transplant-related complications (n=1). One patient relapsed and died after receiving a transplant; so in total, 5 (10%) patients have died. Among 20 (38%) patients who received a transplant in first CR, 18 (90%) were either MRD positive at day 28 or a SER. The EFS, RR, OS rates at 5 years were 78% (61–88%), 16% (7–34%) and 89% (76–95%), respectively (figure). There were no significant differences in outcome according to sex, age, WCC, NCI risk status or MRD levels at day 28. Interestingly, among the 5 relapses who had MRD measured at day 28 only 1 was positive (>0.01%); although 2 more had borderline levels (>0.005%).A comparison between the outcome of iAMP21 patients treated on ALL97 and ALL2003 showed a statistically significant decrease in RR (p<0.0001) with significant increases in EFS (p<0.0001) and OS (p<0.01). The key endpoint was the proportion of patients suffering a relapse which decreased nearly seven-fold (81% to 12%) between the two trials. Importantly none of the ALL2003 relapses occurred on treatment and all bar one were classified as late events (>6 months after the end of treatment). The findings presented herein clearly illustrate the benefit of this treatment intervention in improving survival in these patients who otherwise had an extremely poor outcome when given standard therapy. In light of these results, iAMP21 patients treated on our new trial, ALL2011, will continue to be classified in the high risk cytogenetic subgroup and will receive regimen C. They are recommended for transplant only if they fail to achieve a CR by day 29. This study illustrates how the discovery and characterisation of a disease-specific genetic aberration can be used to tailor therapy more precisely. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Delineation of Risk Factors in Paediatric Acute Lymphoblastic Leukaemia with Favourable Cytogenetics

AbstractAbstract 292▪▪This icon denotes a clinically relevant abstractChildren with ETV6-RUNX1 or high hyperdiploid (HeH, 51–65 chromosomes) acute lymphoblastic leukaemia (ALL) have an excellent prognosis when treated on modern protocols and achieve survival rates in excess of 90% at 5 years. They are prevalent aberrations and together account for nearly 60% cases at diagnosis. Approximately 10–15% patients with these aberrations will suffer a relapse; usually off-treatment. Despite their good outcome their high prevalence means that they account for roughly 40% childhood ALL relapse. Therefore predicting those that will suffer a relapse remains a significant clinical issue. Numerous studies have postulated that certain secondary genetic abnormalities or cytogenetic characteristics correlate with outcome. However, the results have been inconsistent and few abnormalities or characteristics have been studied or confirmed in independent cohorts.In this study, we have investigated the prognostic impact of the major secondary abnormalities and characteristics among ETV6-RUNX1 and HeH patients treated on MRC ALL97/99 between 1997 and 2002. The cohort had a median follow-up time of 8.5 years and survival rates are quoted at 7 years. Additional genetic abnormalities were detected either by fluorescence in situ hybridization (FISH) using probes for ETV6 and RUNX1 or Multiplex Ligation-Dependent Probe Amplification (MLPA) using the SALSA P335 ALL IKZF1 kit. Patients were also analysed by National Cancer Institute (NCI) risk status: standard risk (SR) patient were less than 10 years old with a white cell count (WCC) lower than 50×109/L; high risk (HR) included all other patients.Among 368 ETV6-RUNX1 patients, 47 (13%) relapsed and 20 died (5%) resulting in event free (EFS) and overall survival (OS) rates of 88% and 96%, respectively. The majority of patients were SR (n=283, 77%) and although they did not have a significantly lower relapse rate (32/283 (11%) v 15/85 (18%), p=0.14) they did have a lower death rate (8/283 (3%) v 12/85 (14%), p<0.001). Accordingly, HR patients had significantly inferior EFS and OS rates compared to SR patients: 76% v 90% (p=0.001) and 87% v 99% (p<0.001). A total of 247 (67%) patients were screened using FISH probes designed to detect deletions of the non-rearranged ETV6 allele (n=165, 67%), gain of chromosome 21 (n=57, 23%) and gain of der(21)t(12;21) (n=38, 16%). Analysis of these secondary abnormalities within NCI risk groups did not reveal any association with outcome. The incidence of micro-deletions detected by MLPA among 114 patients was: ETV6 (65%), PAX5 (27%), CDKN2A/B (23%), BTG1 (21%), RB1 (8%), IKZF1 (5%), EBF1 (4%). There was no difference in the distribution of micro-deletions between SR and HR patients and none of the deletions were associated with outcome in the two risk groups.Among 553 HeH patients, 81 (15%) relapsed and 48 (9%) died resulting in EFS and OS rates of 83% and 91%, respectively. The majority of patients were SR (79%) with a significantly lower relapse and death rate: 57/439 (13%) v 24/114 (21%), p=0.033 and 30/439 (7%) v 18/114 (16%), p=0.002). HR patients had significantly inferior EFS and OS rates compared to SR patients: 76% v 85% (p=0.03) and 85% v 94% (p=0.002). HeH karyotypes were classified according to the presence of triple trisomy (+4,+10,+17) (47%), double trisomy (+4,+10) (60%), trisomy 18 (78%) and modal chromosome number (51–53, 21%; 54–57, 56%; 58–65, 23%). Only the incidence of trisomy 18 varied by NCI risk status: SR 80% v HR 69%, p=0.016. The incidence of micro-deletions detected among 144 patients was similar for SR and HR patients: CDKN2A/B (16%), IKZF1 (9%), ETV6 (8%), PAX5 (3%), RB1 (3%), BTG1 (1%) and EBF1 (0%). Among SR patients only trisomy 18 was significantly associated with a good outcome: EFS 88% v 73% (p=0.0013); OS 96% v 90% (p=0.016). There were no significant risk factors among the HR group; although all 4 patients with an IKZF1 deletion relapsed.In contrast to previous studies most secondary genetic abnormalities or cytogenetic characteristics were not associated with outcome in this study. Although NCI HR patients did have a significantly inferior outcome compared to their SR counterparts with the same chromosomal abnormality, the EFS and OS rates at 7 years were in excess of 75%, highlighting the excellent prognosis for patients with these abnormalities. These findings support the risk stratification of ETV6-RUNX1 and HeH patients by NCI risk status on current protocols. Disclosures:No relevant conflicts of interest to declare.

Extremes of Weight Are Associated with Increased Treatment-Related Toxicity in High-Risk Acute Lymphoblastic Leukemia: A Report From the Children's Oncology Group,

Abstract 3574▪▪This icon denotes a clinically relevant abstractIntensification of therapy for acute lymphoblastic leukemia (ALL) has improved long-term survival but is associated with considerable treatment-related toxicity (TRT). While obesity has been shown to affect event-free survival (EFS) and overall survival (OS) in ALL, little information exists as to the effect of extremes of weight (underweight or obese) on morbidity due to TRT. To this end, we conducted a secondary analysis of 1,902 children treated on the Children’s Oncology Group study CCG-1961 to determine whether weight extremes influence development of TRT and EFS/OS in children with higher risk ALL. CCG-1961 was a randomized study for patients 1–21 years old with National Cancer Institute High-Risk ALL (HR-ALL) that evaluated marrow response at day 7 of Induction and compared regimens of differing intensity and/or duration (for Rapid Early Responders, RER) or anthracycline used in Delayed Intensification (for Slow Early Responders, SER). Weight category was determined using the United States Centers for Disease Control and Prevention Z-scores for body mass index (BMI) by age (age ≥ 2 yrs) and weight by length (age <2 years). Extremes of weight were defined as underweight (< 5th percentile) and obese (> 95th percentile). At diagnosis, 107 patients (5.6%) were underweight and 264 were obese (13.9%). Multivariate linear and logistic regression analyses controlled for age, gender, race/ethnicity, payer type (as a surrogate for socioeconomic status), initial white blood cell count, presence of central nervous system disease, RER/SER status, and phase of treatment independent of regimen. All of the preceding predictors were independently significantly associated with development of grade 3/4 non-hematological toxicity in multivariate analysis (p<0.05). Data used for analysis were sourced from participating sites through routinely reported study forms (toxicity graded per Children’s Cancer Group Toxicity and Complications Criteria).Our results demonstrate statistically significant increases in toxicity for both extremes of weight. Weight category at start of each phase was predictive of developing grade 3/4 non-hematological toxicity during that phase (p<0.001). In comparison with healthy/overweight patients (5th – 95th%), underweight patients were at increased risk for developing fungemia (odds ratio [OR] 3.45, 95% confidence interval [95% CI] 1.25–9.50; p=0.017), fungal pulmonary infections (OR 2.54, 95% CI 1.05–6.11; p=0.040), and bacteremia (OR 1.33, 95% CI 1.04–1.71; p=0.020). Underweight patients also required significantly more hematopoietic support per phase with at least one transfusion of packed red blood cells (OR 1.62, 95% CI 1.31–1.99; p<0.001) or platelets (OR 1.42, 95% CI 1.16–1.75; p=0.001), as well as use of granulocyte colony-stimulating factor (OR 1.40, 95% CI 1.00–1.96; p=0.052). Underweight patients had slightly longer hospitalizations by 1 day per treatment phase (p<0.001). In contrast, obese patients had no increased risk of infection but exhibited increased toxicity of the liver as indicated by the presence of transaminitis or hyperbilirubinemia (OR 1.23, 95% CI 1.11–1.36, p<0.001) and increased incidence of pancreatitis (OR 1.30, 95% CI 1.08–1.56; p=0.005). There was no significant difference in the occurrence of other organ toxicities, including cardiac, renal, gastrointestinal and nervous systems. With a median follow-up of 7.1 years, healthy/overweight patients had an EFS of 71% as compared to EFS for underweight patients 63% (Hazard Ratio [HR] 1.33, 95% CI 0.95 – 1.87, p = 0.097) and obese patients 65% (HR 1.25, 95%CI 1.00–1.57, p=0.051). OS was not significantly different among the 3 weight classifications.Our data indicate that for children with HR-ALL, extremes of weight are associated with significantly increased risk for TRT that is more infectious/hematopoietic in underweight patients and more hepatic/pancreatic in obese patients. With a median follow-up of 7.1 years, EFS was lower at both weight extremes versus healthy/overweight children, but in this analysis did not reach statistical significance. These findings provide insights into the nutritional status of children and adolescents with ALL that could lead to interventions designed to mitigate the impact of weight extremes upon their tolerance of therapy, quality of life and survival. Disclosures:No relevant conflicts of interest to declare.