Induction chemotherapy fails to induce a complete remission in only about 2 to 3% of children with ALL. In an analysis of more than 1000 such patients, the authors defined subgroups with a favorable ...prognosis and those with an unfavorable prognosis.
Current treatment for acute lymphoblastic leukemia (ALL) can effect a cure in approximately 80% of children with the disease.
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The leading cause of treatment failure is relapse, for which a number of risk factors have been identified, with inadequate therapy being one of the most important.
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A small but significant percentage of patients do not have a complete remission after 4 to 6 weeks of induction chemotherapy.
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Among patients with initial induction failure, some never have a complete remission and most others have early relapse. Because of the rarity of induction failure, affected patients have been collectively . . .
To review the impact of collaborative studies on advances in the biology and treatment of acute lymphoblastic leukemia (ALL) in children and adolescents.
A review of English literature on childhood ...ALL focusing on collaborative studies was performed. The resulting article was reviewed and revised by the committee chairs of the major ALL study groups.
With long-term survival rates for ALL approaching 90% and the advent of high-resolution genome-wide analyses, several international study groups or consortia were established to conduct collaborative research to further improve outcome. As a result, treatment strategies have been improved for several subtypes of ALL, such as infant, MLL-rearranged, Philadelphia chromosome-positive, and Philadelphia chromosome-like ALL. Many recurrent genetic abnormalities that respond to tyrosine kinase inhibitors and multiple genetic determinants of drug resistance and toxicities have been identified to help develop targeted therapy. Several genetic polymorphisms have been recognized that show susceptibility to developing ALL and that help explain the racial/ethnic differences in the incidence of ALL.
The information gained from collaborative studies has helped decipher the heterogeneity of ALL to help improve personalized treatment, which will further advance the current high cure rate and the quality of life for children and adolescents with ALL.
L-asparaginase is an integral component of therapy for acute lymphoblastic leukemia. However, asparaginase-related complications, including the development of hypersensitivity reactions, can limit ...its use in individual patients. Of considerable concern in the setting of clinical allergy is the development of neutralizing antibodies and associated asparaginase inactivity. Also problematic in the use of asparaginase is the potential for the development of silent inactivation, with the formation of neutralizing antibodies and reduced asparaginase activity in the absence of a clinically evident allergic reaction. Here we present guidelines for the identification and management of clinical hypersensitivity and silent inactivation with Escherichia coli- and Erwinia chrysanthemi- derived asparaginase preparations. These guidelines were developed by a consensus panel of experts following a review of the available published data. We provide a consensus of expert opinions on the role of serum asparaginase level assessment, indications for switching asparaginase preparation, and monitoring after change in asparaginase preparation.
Summary Although there are high survival rates for children with acute lymphoblastic leukaemia, their outcome is often counterbalanced by the burden of toxic effects. This is because reported ...frequencies vary widely across studies, partly because of diverse definitions of toxic effects. Using the Delphi method, 15 international childhood acute lymphoblastic leukaemia study groups assessed acute lymphoblastic leukaemia protocols to address toxic effects that were to be considered by the Ponte di Legno working group. 14 acute toxic effects (hypersensitivity to asparaginase, hyperlipidaemia, osteonecrosis, asparaginase-associated pancreatitis, arterial hypertension, posterior reversible encephalopathy syndrome, seizures, depressed level of consciousness, methotrexate-related stroke-like syndrome, peripheral neuropathy, high-dose methotrexate-related nephrotoxicity, sinusoidal obstructive syndrome, thromboembolism, and Pneumocystis jirovecii pneumonia) that are serious but too rare to be addressed comprehensively within any single group, or are deemed to need consensus definitions for reliable incidence comparisons, were selected for assessment. Our results showed that none of the protocols addressed all 14 toxic effects, that no two protocols shared identical definitions of all toxic effects, and that no toxic effect definition was shared by all protocols. Using the Delphi method over three face-to-face plenary meetings, consensus definitions were obtained for all 14 toxic effects. In the overall assessment of outcome of acute lymphoblastic leukaemia treatment, these expert opinion-based definitions will allow reliable comparisons of frequencies and severities of acute toxic effects across treatment protocols, and facilitate international research on cause, guidelines for treatment adaptation, preventive strategies, and development of consensus algorithms for reporting on acute lymphoblastic leukaemia treatment.
Pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is associated with a high frequency of copy number alterations (CNAs) in IKZF1, EBF1, PAX5, CDKN2A/B, RB1, BTG1, ETV6, and/or the ...PAR1 region (henceforth: B-cell development genes). We aimed to gain insight in the association between CNAs in these genes, clinical outcome parameters, and cellular drug resistance. 71% of newly diagnosed pediatric BCP-ALL cases harbored one or more CNAs in these B-cell development genes. The distribution and clinical relevance of these CNAs was highly subtype-dependent. In the DCOG-ALL10 cohort, only loss of IKZF1 associated as single marker with unfavorable outcome parameters and cellular drug resistance. Prednisolone resistance was observed in IKZF1-deleted primary high hyperdiploid cells (~1500-fold), while thiopurine resistance was detected in IKZF1-deleted primary BCR-ABL1-like and non-BCR-ABL1-like B-other cells (~2.7-fold). The previously described risk stratification classifiers, i.e. IKZF1
and integrated cytogenetic and CNA classification, both predicted unfavorable outcome in the DCOG-ALL10 cohort, and associated with ex vivo drug cellular resistance to thiopurines, or L-asparaginase and thiopurines, respectively. This resistance could be attributed to overrepresentation of BCR-ABL1-like cases in these risk groups. Taken together, our data indicate that the prognostic value of CNAs in B-cell development genes is linked to subtype-related drug responses.
Interaction of malignancies with tissue-specific immune cells has gained interest for prognosis and intervention of emerging immunotherapies. We analyzed bone marrow T cells (bmT) as ...tumor-infiltrating lymphocytes in pediatric precursor-B cell acute lymphoblastic leukemia (ALL). Based on data from 100 patients, we show that ALL is associated with late-stage CD4
phenotype and loss of early CD8
T cells. The inhibitory exhaustion marker TIM-3 on CD4
bmT increased relapse risk (RFS = 94.6/70.3%) confirmed by multivariate analysis. The hazard ratio of TIM-3 expression nearly reached the hazard ratio of MRD (7.1 vs. 8.0) indicating that patients with a high frequency of TIM-3
CD4
bone marrow T cells at initial diagnosis have a 7.1-fold increased risk to develop ALL relapse. Comparison of wild type primary T cells to CRISPR/Cas9-mediated TIM-3 knockout and TIM-3 overexpression confirmed the negative effect of TIM-3 on T cell responses against ALL. TIM-3
CD4
bmT are increased in ALL overexpressing CD200, that leads to dysfunctional antileukemic T cell responses. In conclusion, TIM-3-mediated interaction between bmT and leukemia cells is shown as a strong risk factor for relapse in pediatric B-lineage ALL. CD200/TIM-3-signaling, rather than PD-1/PD-L1, is uncovered as a mechanism of T cell dysfunction in ALL with major implication for future immunotherapies.
Summary Background Trials of imatinib have provided evidence of activity in adults with Philadelphia-chromosome-positive acute lymphoblastic leukaemia (ALL), but the drug's role when given with ...multidrug chemotherapy to children is unknown. This study assesses the safety and efficacy of oral imatinib in association with a Berlin–Frankfurt–Munster intensive chemotherapy regimen and allogeneic stem-cell transplantation for paediatric patients with Philadelphia-chromosome-positive ALL. Methods Patients aged 1–18 years recruited to national trials of front-line treatment for ALL were eligible if they had t(9;22)(q34;q11). Patients with abnormal renal or hepatic function, or an active systemic infection, were ineligible. Patients were enrolled by ten study groups between 2004 and 2009, and were classified as good risk or poor risk according to early response to induction treatment. Good-risk patients were randomly assigned by a web-based system with permuted blocks (size four) to receive post-induction imatinib with chemotherapy or chemotherapy only in a 1:1 ratio, while all poor-risk patients received post-induction imatinib with chemotherapy. Patients were stratified by study group. The chemotherapy regimen was modelled on a Berlin–Frankfurt–Munster high-risk backbone; all received four post-induction blocks of chemotherapy after which they became eligible for stem-cell transplantation. The primary endpoints were disease-free survival at 4 years in the good-risk group and event-free survival at 4 years in the poor-risk group, analysed by intention to treat and a secondary analysis of patients as treated. The trial is registered with EudraCT (2004-001647-30) and ClinicalTrials.gov , number NCT00287105. Findings Between Jan 1, 2004, and Dec 31, 2009, we screened 229 patients and enrolled 178: 108 were good risk and 70 poor risk. 46 good-risk patients were assigned to receive imatinib and 44 to receive no imatinib. Median follow-up was 3·1 years (IQR 2·0–4·6). 4-year disease-free survival was 72·9% (95% CI 56·1–84·1) in the good-risk, imatinib group versus 61·7% (45·0–74·7) in the good-risk, no imatinib group (p=0·24). The hazard ratio (HR) for failure, adjusted for minimal residual disease, was 0·63 (0·28–1·41; p=0·26). The as-treated analysis showed 4-year disease-free survival was 75·2% (61·0–84·9) for good-risk patients receiving imatinib and 55·9% (36·1–71·7) for those who did not receive imatinib (p=0·06). 4-year event-free survival for poor-risk patients was 53·5% (40·4–65·0). Serious adverse events were much the same in the good-risk groups, with infections caused by myelosuppression the most common. 16 patients in the good-risk imatinib group versus ten in the good-risk, no imatinib group (p=0·64), and 24 in the poor-risk group, had a serious adverse event. Interpretation Our results suggests that imatinib in conjunction with intensive chemotherapy is well tolerated and might be beneficial for treatment of children with Philadelphia-chromosome-positive ALL. Funding Projet Hospitalier de Recherche Clinique-Cancer (France), Fondazione Tettamanti-De Marchi and Associazione Italiana per la Ricerca sul Cancro (Italy), Novartis Germany, Cancer Research UK, Leukaemia Lymphoma Research, and Central Manchester University Hospitals Foundation Trust.
The multicenter trial ALL-REZ BFM (ie, Acute Lymphoblastic Leukemia Relapse Berlin-Frankfurt-Münster) 90 was designed to improve prognosis for children with relapsed acute lymphoblastic leukemia ...(ALL) by time-to-relapse- and site-of-relapse-adapted stratification and by introduction of novel chemotherapy elements and to evaluate new prognostic parameters in a large, population-based cohort.
Five hundred twenty-five patients stratified into risk groups A (early bone marrow BM relapses), B (late BM relapses), and C (isolated extramedullary relapses) received alternating short-course intensive polychemotherapy (in blocks R1, R2, or R3) and cranial/craniospinal irradiation followed by maintenance therapy. Block R3 (high-dose cytarabine and etoposide) was introduced to improve the outcome compared with historical controls. Patients with early BM or T-ALL relapse (poor prognosis group PPG) were eligible for experimental regimens. One hundred seventeen patients received stem-cell transplantation (SCT).
The probabilities (and standard deviations) of event-free survival (pEFS) and overall survival (pOS) at 10 years were 0.30 +/- .02 and 0.36 +/- .02, respectively. Significant differences existed between strategic groups (pEFS(A) = .17 +/- .03; pEFS(B) = .43 +/- .04; pEFS(C) = .54 +/- .06; pEFS(PPG) = .15 +/- .03; log-rank P < .001). Patients of high-risk groups A plus PPG did better with SCT than with chemotherapy (pEFS = .33 +/- .05 v 0.20 +/- .05; P = .005). The pEFS was similar to trials ALL-REZ BFM 85/87 (.36 +/- .03. v 0.37 +/- .03; P = .419; PPG excluded). Time point, site of relapse, immunophenotype, and SCT were significant predictors of pEFS in multivariate analyses.
More than one third of patients in this large, population-based trial were cured. Neither R3 nor adaptation of chemotherapy intensity was capable of improving pEFS or of overcoming prognostic factors. In high-risk patients, remission induction regimens must be improved, and allogeneic SCT should be recommended in patients achieving second complete remission.
In children with intermediate risk of relapse of acute lymphoblastic leukemia (ALL), it is essential to identify patients in need of treatment intensification. We hypothesized that the prognosis of ...patients with unsatisfactory reduction of minimal residual disease (MRD) can be improved by allogeneic hematopoietic stem-cell transplantation (HSCT).
In the Acute Lymphoblastic Leukemia-Relapse Study of the Berlin-Frankfurt-Münster Group (ALL-REZ BFM) 2002, patients with an MRD level of ≥ 10(-3) (n = 99) at the end of induction therapy were allocated to HSCT, whereas those with an MRD level less than 10(-3) (n = 109) continued to receive chemotherapy. MRD was quantified by real-time polymerase chain reaction for clone-specific T-cell receptor/immunoglobulin gene rearrangements.
The probability of event-free survival for patients with MRD ≥ 10(-3) was 64% ± 5% in ALL-REZ BFM 2002 compared with 18% ± 7% in the predecessor study ALL-REZ BFM P95/96 (P < .001). This was mainly achieved by reducing the cumulative incidence of subsequent relapse (CIR) at 8 years from 59% ± 9% to 27% ± 5% (P < .001). The favorable prognosis of patients with MRD less than 10(-3) could be confirmed in those with a late combined or isolated bone marrow B-cell precursor (BCP) -ALL relapse (CIR, 20% ± 5%), whereas patients with an early combined BCP-ALL relapse had an unfavorable outcome (CIR, 63% ± 13%; P < .001).
Allogeneic HSCT markedly improved the prognosis of patients with intermediate risk of relapse of ALL and unsatisfactory MRD response. As a result, outcomes in this group approximated those of patients with favorable MRD response. Patients with early combined relapse require treatment intensification even in case of favorable MRD response, demonstrating the prognostic impact of time to relapse.
Comparison of treatment strategies in de novo pediatric acute lymphoblastic leukemia (ALL) requires standardized measures of efficacy. Key parameters that define disease-related events, including ...complete remission (CR), treatment failure (TF; not achieving CR), and relapse (loss of CR) require an updated consensus incorporating modern diagnostics. We collected the definitions of CR, TF, and relapse from recent and current pediatric clinical trials for the treatment of ALL, including the key components of response evaluation (timing, anatomic sites, detection methods, and thresholds) and found significant heterogeneity, most notably in the definition of TF. Representatives of the major international ALL clinical trial groups convened to establish consensus definitions. CR should be defined at a time point no earlier than at the end of induction and should include the reduction of blasts below a specific threshold in bone marrow and extramedullary sites, incorporating minimal residual disease (MRD) techniques for marrow evaluations. TF should be defined as failure to achieve CR by a prespecified time point in therapy. Relapse can only be defined in patients who have achieved CR and must include a specific threshold of leukemic cells in the bone marrow confirmed by MRD, the detection of central nervous system leukemia, or documentation of extramedullary disease. Definitions of TF and relapse should harmonize with eligibility criteria for clinical trials in relapsed/refractory ALL. These consensus definitions will enhance the ability to compare outcomes across pediatric ALL trials and facilitate development of future international collaborative trials.