Survival for children and young adults with high-risk B-acute lymphoblastic leukemia has improved significantly, but 20% to 25% of patients are not cured. Children's Oncology Group study AALL0232 ...tested two interventions to improve survival.
Between January 2004 and January 2011, AALL0232 enrolled 3,154 participants 1 to 30 years old with newly diagnosed high-risk B-acute lymphoblastic leukemia. By using a 2 × 2 factorial design, 2,914 participants were randomly assigned to receive dexamethasone (14 days) versus prednisone (28 days) during induction and high-dose methotrexate versus Capizzi escalating-dose methotrexate plus pegaspargase during interim maintenance 1.
Planned interim monitoring showed the superiority of the high-dose methotrexate regimens, which exceeded the predefined boundary and led to cessation of enrollment in January 2011. At that time, participants randomly assigned to high-dose methotrexate during interim maintenance 1 versus those randomly assigned to Capizzi methotrexate had a 5-year event-free survival (EFS) of 82% versus 75.4% (P = .006). Mature final data showed 5-year EFS rates of 79.6% for high-dose methotrexate and 75.2% for Capizzi methotrexate (P = .008). High-dose methotrexate decreased both marrow and CNS recurrences. Patients 1 to 9 years old who received dexamethasone and high-dose methotrexate had a superior outcome compared with those who received the other three regimens (5-year EFS, 91.2% v 83.2%, 80.8%, and 82.1%; P = .015). Older participants derived no benefit from dexamethasone during induction and experienced excess rates of osteonecrosis.
High-dose methotrexate is superior to Capizzi methotrexate for the treatment of high-risk B-acute lymphoblastic leukemia, with no increase in acute toxicity. Dexamethasone given during induction benefited younger children but provided no benefit and was associated with a higher risk of osteonecrosis among participants 10 years and older.
Adults and children with high-risk CRLF2-rearranged acute lymphoblastic leukemia (ALL) respond poorly to current cytotoxic chemotherapy and suffer unacceptably high rates of relapse, supporting the ...need to use alternative therapies. CRLF2 encodes the thymic stromal lymphopoietin (TSLP) receptor, which activates cell signaling in normal lymphocytes on binding its ligand, TSLP. We hypothesized that aberrant cell signaling occurs in CRLF2-rearranged ALL and can be targeted by signal transduction inhibitors of this pathway. In a large number of primary CRLF2-rearranged ALL samples, we observed increased basal levels of pJAK2, pSTAT5, and pS6. We thus characterized the biochemical sequelae of CRLF2 and JAK alterations in CRLF2-rearranged ALL primary patient samples via analysis of TSLP-mediated signal transduction. TSLP stimulation of these leukemias further induced robust JAK/STAT and PI3K/mTOR pathway signaling. JAK inhibition abrogated phosphorylation of JAK/STAT and, surprisingly, of PI3K/mTOR pathway members, suggesting an interconnection between these signaling networks and providing a rationale for testing JAK inhibitors in clinical trials. The PI3K/mTOR pathway inhibitors rapamycin, PI103, and PP242 also inhibited activated signal transduction and translational machinery proteins of the PI3K/mTOR pathway, suggesting that signal transduction inhibitors targeting this pathway also may have therapeutic relevance for patients with CRLF2-rearranged ALL and merit further preclinical testing.
Although inotuzumab ozogamicin (InO) is recognized as an effective agent in relapsed acute lymphoblastic leukemia (ALL) in adults, data on safety and efficacy in pediatric patients are scarce. We ...report the use of InO in 51 children with relapsed/refractory ALL treated in the compassionate use program. In this heavily pretreated cohort, complete remission was achieved in 67% of patients with overt marrow disease. The majority (71%) of responders were negative for minimal residual disease. Responses were observed irrespective of cytogenetic subtype or number or type of prior treatment regimens. InO was well-tolerated; grade 3 hepatic transaminitis or hyperbilirubinemia were noted in 6 (12%) and grade 3/4 infections in 11 (22%) patients. No patient developed sinusoidal obstruction syndrome (SOS) during InO therapy; however, 11 of 21 (52%) patients who underwent hematopoietic stem cell transplantation (HSCT) following InO developed SOS. Downregulation of surface CD22 was detected as a possible escape mechanism in three patients who developed a subsequent relapse after InO. We conclude that InO is a well-tolerated, effective therapy for children with relapsed ALL and prospective studies are warranted. Identification of risk factors for developing post-HSCT SOS and strategies to mitigate this risk are ongoing.
Early intensification with methotrexate (MTX) is a key component of acute lymphoblastic leukemia (ALL) therapy. Two different approaches to MTX intensification exist but had not been compared in ...T-cell ALL (T-ALL): the Children's Oncology Group (COG) escalating dose intravenous MTX without leucovorin rescue plus pegaspargase escalating dose, Capizzi-style, intravenous MTX (C-MTX) regimen and the Berlin-Frankfurt-Muenster (BFM) high-dose intravenous MTX (HDMTX) plus leucovorin rescue regimen.
COG AALL0434 included a 2 × 2 randomization that compared the COG-augmented BFM (ABFM) regimen with either C-MTX or HDMTX during the 8-week interim maintenance phase. All patients with T-ALL, except for those with low-risk features, received prophylactic (12 Gy) or therapeutic (18 Gy for CNS3) cranial irradiation during either the consolidation (C-MTX; second month of therapy) or delayed intensification (HDMTX; seventh month of therapy) phase.
AALL0434 accrued 1,895 patients from 2007 to 2014. The 5-year event-free survival and overall survival rates for all eligible, evaluable patients with T-ALL were 83.8% (95% CI, 81.2% to 86.4%) and 89.5% (95% CI, 87.4% to 91.7%), respectively. The 1,031 patients with T-ALL but without CNS3 disease or testicular leukemia were randomly assigned to receive ABFM with C-MTX (n = 519) or HDMTX (n = 512). The estimated 5-year disease-free survival ( P = .005) and overall survival ( P = .04) rates were 91.5% (95% CI, 88.1% to 94.8%) and 93.7% (95% CI, 90.8% to 96.6%) for C-MTX and 85.3% (95% CI, 81.0%-89.5%) and 89.4% (95% CI, 85.7%-93.2%) for HDMTX. Patients assigned to C-MTX had 32 relapses, six with CNS involvement, whereas those assigned to HDMTX had 59 relapses, 23 with CNS involvement.
AALL0434 established that ABFM with C-MTX was superior to ABFM plus HDMTX for T-ALL in approximately 90% of patients who received CRT, with later timing for those receiving HDMTX.
Known clinical and genetic markers have limitations in predicting disease course and outcome in juvenile myelomonocytic leukemia (JMML). DNA methylation patterns in JMML have correlated with outcome ...across multiple studies, suggesting it as a biomarker to improve patient stratification. However, standardized approaches to classify JMML on the basis of DNA methylation patterns are lacking. We, therefore, sought to define an international consensus for DNA methylation subgroups in JMML and develop classification methods for clinical implementation.
Published DNA methylation data from 255 patients with JMML were used to develop and internally validate a classifier model. Accuracy across platforms (EPIC-arrays and MethylSeq) was tested using a technical validation cohort (32 patients). The suitability of both methods for single-patient classification was demonstrated using an independent cohort (47 patients).
Analysis of pooled, published data established three DNA methylation subgroups as a
standard. Unfavorable prognostic parameters (
mutation, elevated fetal hemoglobin, and older age) were significantly enriched in the high methylation (HM) subgroup. A classifier was then developed that predicted subgroups with 98% accuracy across different technological platforms. Applying the classifier to an independent validation cohort confirmed an association of HM with secondary mutations, high relapse incidence, and inferior overall survival (OS), while the low methylation subgroup was associated with a favorable disease course. Multivariable analysis established DNA methylation subgroups as the only significant factor predicting OS.
This study provides an international consensus definition for DNA methylation subgroups in JMML. We developed and validated methods which will facilitate the design of risk-stratified clinical trials in JMML.
Juvenile myelomonocytic leukemia (JMML) is a myeloproliferative disorder of childhood caused by mutations in the Ras pathway. Outcomes in JMML vary markedly from spontaneous resolution to rapid ...relapse after hematopoietic stem cell transplantation. Here, we hypothesized that DNA methylation patterns would help predict disease outcome and therefore performed genome-wide DNA methylation profiling in a cohort of 39 patients. Unsupervised hierarchical clustering identifies three clusters of patients. Importantly, these clusters differ significantly in terms of 4-year event-free survival, with the lowest methylation cluster having the highest rates of survival. These findings were validated in an independent cohort of 40 patients. Notably, all but one of 14 patients experiencing spontaneous resolution cluster together and closer to 22 healthy controls than to other JMML cases. Thus, we show that DNA methylation patterns in JMML are predictive of outcome and can identify the patients most likely to experience spontaneous resolution.
There is increasing evidence for a strong inherited genetic basis of susceptibility to acute lymphoblastic leukaemia (ALL) in children. To identify new risk variants for B-cell ALL (B-ALL) we ...conducted a meta-analysis with four GWAS (genome-wide association studies), totalling 5321 cases and 16,666 controls of European descent. We herein describe novel risk loci for B-ALL at 9q21.31 (rs76925697, P = 2.11 × 10
), for high-hyperdiploid ALL at 5q31.1 (rs886285, P = 1.56 × 10
) and 6p21.31 (rs210143 in BAK1, P = 2.21 × 10
), and ETV6-RUNX1 ALL at 17q21.32 (rs10853104 in IGF2BP1, P = 1.82 × 10
). Particularly notable are the pleiotropic effects of the BAK1 variant on multiple haematological malignancies and specific effects of IGF2BP1 on ETV6-RUNX1 ALL evidenced by both germline and somatic genomic analyses. Integration of GWAS signals with transcriptomic/epigenomic profiling and 3D chromatin interaction data for these leukaemia risk loci suggests deregulation of B-cell development and the cell cycle as central mechanisms governing genetic susceptibility to ALL.
Acute lymphoblastic leukemia (ALL) is the most common cancer in children and the incidence of ALL varies by ethnicity. Although accumulating evidence indicates inherited predisposition to ALL, the ...genetic basis of ALL susceptibility in diverse ancestry has not been comprehensively examined.
We performed a multiethnic genome-wide association study in 1605 children with ALL and 6661 control subjects after adjusting for population structure, with validation in three replication series of 845 case subjects and 4316 control subjects. Association was tested by two-sided logistic regression.
A novel ALL susceptibility locus at 10p12.31-12.2 (BMI1-PIP4K2A, rs7088318, P = 1.1 × 10(-11)) was identified in the genome-wide association study, with independent replication in European Americans, African Americans, and Hispanic Americans (P = .001, .009, and .04, respectively). Association was also validated at four known ALL susceptibility loci: ARID5B, IKZF1, CEBPE, and CDKN2A/2B. Associations at ARID5B, IKZF1, and BMI1-PIP4K2A variants were consistent across ethnicity, with multiple independent signals at IKZF1 and BMI1-PIP4K2A loci. The frequency of ARID5B and BMI1-PIP4K2A variants differed by ethnicity, in parallel with ethnic differences in ALL incidence. Suggestive evidence for modifying effects of age on genetic predisposition to ALL was also observed. ARID5B, IKZF1, CEBPE, and BMI1-PIP4K2A variants cumulatively conferred strong predisposition to ALL, with children carrying six to eight copies of risk alleles at a ninefold (95% confidence interval = 6.9 to 11.8) higher ALL risk relative to those carrying zero to one risk allele at these four single nucleotide polymorphisms.
These findings indicate strong associations between inherited genetic variation and ALL susceptibility in children and shed new light on ALL molecular etiology in diverse ancestry.
Children's Oncology Group (COG) AALL0331 tested whether intensified postinduction therapy that improves survival in children with high-risk B-cell acute lymphoblastic leukemia (ALL) would also ...improve outcomes for those with standard-risk (SR) ALL.
AALL0331 enrolled 5,377 patients between 2005 and 2010. All patients received a 3-drug induction with dexamethasone, vincristine, and pegaspargase (PEG) and were then classified as SR low, SR average, or SR high. Patients with SR-average disease were randomly assigned to receive either standard 4-week consolidation (SC) or 8-week intensified augmented Berlin-Frankfurt-Münster (BFM) consolidation (IC). Those with SR-high disease were nonrandomly assigned to the full COG-augmented BFM regimen, including 2 interim maintenance and delayed intensification phases.
The 6-year event-free survival (EFS) rate for all patients enrolled in AALL0331 was 88.96% ± 0.46%, and overall survival (OS) was 95.54% ± 0.31%. For patients with SR-average disease, the 6-year continuous complete remission (CCR) and OS rates for SC versus IC were 87.8% ± 1.3% versus 89.1% ± 1.2% (
= .52) and 95.8% ± 0.8% versus 95.2% ± 0.8% (
= 1.0), respectively. Those with SR-average disease with end-induction minimal residual disease (MRD) of 0.01% to < 0.1% had an inferior outcome compared with those with lower MRD and no improvement with IC (6-year CCR: SC, 77.5% ± 4.8%; IC, 77.1% ± 4.8%;
= .71). At 6 years, the CCR and OS rates among 635 nonrandomly treated patients with SR-high disease were 85.55% ± 1.49% and 92.97% ± 1.08%, respectively.
The 6-year OS rate for > 5,000 children with SR ALL enrolled in AALL0331 exceeded 95%. The addition of IC to treatment for patients with SR-average disease did not improve CCR or OS, even in patients with higher MRD, in whom it might have been predicted to provide more value. The EFS and OS rates are excellent for this group of patients with SR ALL, with particularly good outcomes for those with SR-high disease.
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