Ursula Creutzig

Improved Outcome in Pediatric Relapsed Acute Myeloid Leukemia: Results of a Randomized Trial on Liposomal Daunorubicin by the International BFM Study Group

PURPOSEnIn pediatric relapsed acute myeloid leukemia (AML), optimal reinduction therapy is unknown. Studies suggest that liposomal daunorubicin (DNX; DaunoXome; Galen, Craigavon, United Kingdom) is effective and less cardiotoxic, which is important in this setting. These considerations led to a randomized phase III study by the International Berlin-Frankfurt-Münster Study Group.nnnPATIENTS AND METHODSnPatients with relapsed or primary refractory non-French-American-British type M3 AML who were younger than 21 years of age were eligible. Patients were randomly assigned to fludarabine, cytarabine, and granulocyte colony-stimulating factor (FLAG) or to FLAG plus DNX in the first reinduction course. The primary end point was status of the bone marrow (BM) sampled shortly before the second course of chemotherapy (the day 28 BM). Data are presented according to intention-to-treat for all 394 randomly assigned patients (median follow-up, 4.0 years).nnnRESULTSnThe complete remission (CR) rate was 64%, and the 4-year probability of survival (pOS) was 38% (SE, 3%). The day 28 BM status (available in 359 patients) was good (≤ 20% leukemic blasts) in 80% of patients randomly assigned to FLAG/DNX and 70% for patients randomly assigned to FLAG (P = .04). Concerning secondary end points, the CR rate was 69% with FLAG/DNX and 59% with FLAG (P = .07), but overall survival was similar. However, core-binding factor (CBF) AML treated with FLAG/DNX resulted in pOS of 82% versus 58% with FLAG (P = .04). Grade 3 to 4 toxicity was essentially similar in both groups.nnnCONCLUSIONnDNX added to FLAG improves early treatment response in pediatric relapsed AML. Overall long-term survival was similar, but CBF-AML showed an improved survival with FLAG/DNX. International collaboration proved feasible and resulted in the best outcome for pediatric relapsed AML reported thus far.

Randomized trial comparing liposomal daunorubicin with idarubicin as induction for pediatric acute myeloid leukemia: results from Study AML-BFM 2004

Outcomes of patients with acute myeloid leukemia (AML) improve significantly by intensification of induction. To further intensify anthracycline dosage without increasing cardiotoxicity, we compared potentially less cardiotoxic liposomal daunorubicin (L-DNR) to idarubicin at a higher-than-equivalent dose (80 vs 12 mg/m(2) per day for 3 days) during induction. In the multicenter therapy-optimization trial AML-BFM 2004, 521 of 611 pediatric patients (85%) were randomly assigned to L-DNR or idarubicin induction. Five-year results in both treatment arms were similar (overall survival 76% ± 3% [L-DNR] vs 75% ± 3% [idarubicin], Plogrank = .65; event-free survival [EFS] 59% ± 3% vs 53% ± 3%, Plogrank = .25; cumulative incidence of relapse 29% ± 3% vs 31% ± 3%, P(Gray) = .75), as were EFS results for standard (72% ± 5% vs 68% ± 5%, Plogrank = .47) and high-risk (51% ± 4% vs 46% ± 4%, Plogrank = .45) patients. L-DNR resulted in significantly better probability of EFS in patients with t(8;21). Overall, treatment-related mortality was lower with L-DNR than idarubicin (2/257 vs 10/264 patients, P = .04). Grade 3/4 cardiotoxicity was rare after induction (4 L-DNR vs 5 idarubicin). Only 1 L-DNR and 3 idarubicin patients presented with subclinical or mild cardiomyopathy during follow-up. In conclusion, at the given dose, L-DNR has overall antileukemic activity comparable to idarubicin, promises to be more active in subgroups, and causes less treatment-related mortality. This trial was registered at www.clinicaltrials.gov as #NCT00111345.

Collaborative Efforts Driving Progress in Pediatric Acute Myeloid Leukemia

Diagnosis, treatment, response monitoring, and outcome of pediatric acute myeloid leukemia (AML) have made enormous progress during the past decades. Because AML is a rare type of childhood cancer, with an incidence of approximately seven occurrences per 1 million children annually, national and international collaborative efforts have evolved. This overview describes these efforts and includes a summary of the history and contributions of each of the main collaborative pediatric AML groups worldwide. The focus is on translational and clinical research, which includes past, current, and future clinical trials. Separate sections concern acute promyelocytic leukemia, myeloid leukemia of Down syndrome, and relapsed AML. A plethora of novel antileukemic agents that have emerged, including new classes of drugs, are summarized as well. Finally, an important aspect of the treatment of pediatric AML--supportive care--and late effects are discussed. The future is bright, with a wide range of emerging innovative therapies and with more and more international collaboration that ultimately aim to cure all children with AML, with fewer adverse effects and without late effects.

Second induction with high-dose cytarabine and mitoxantrone: different impact on pediatric AML patients with t(8;21) and with inv(16)

Patients with core binding factor acute myeloid leukemia (CBF-AML) benefit from more intensive chemotherapy, but whether both the t(8;21) and inv(16)/t (16;16) subtypes requires intensification remained to be determined. In the 2 successive studies (AML-BFM-1998 and AML-BFM-2004), 220 CBF-AML patients were treated using the same chemotherapy backbone, whereby reinduction with high-dose cytarabine and mitoxantrone (HAM) was scheduled for these cohorts only in study AML-BFM-1998 but not in AML-BFM-2004 against the background to minimize overtreatment. Five-year overall survival (OS) and event-free survival (EFS) were significantly higher and the cumulative incidence of relapse (CIR) lower in t(8;21) patients treated with HAM (n = 78) compared with without HAM (n = 53): OS 92% ± 3% versus 80% ± 6%, p(logrank)0.047, EFS 84% ± 4% versus 59% ± 7%, p(logrank)0.001, and CIR 14% ± 4% versus 34% ± 7%, p((gray))0.006. These differences were not seen for inv(16) (n = 43 and 46, respectively): OS 93% ± 4% versus 94% ± 4%, EFS 75% ± 7% versus 71% ± 9% and CIR 15% ± 6% versus 23% ± 8% (not significant). The subtype t(8;21), but not inv(16), was an independent predictor of worse outcome without HAM reinduction. Based on our data, a 5-year OS of > 90% can be expected for CBF-AML, when stratifying t(8;21), but not inv(16), patients to high-risk chemotherapy, including HAM reinduction.

Clinical Impact of Additional Cytogenetic Aberrations, cKIT and RAS Mutations, and Treatment Elements in Pediatric t(8;21)-AML: Results From an International Retrospective Study by the International Berlin-Frankfurt-Münster Study Group

PURPOSEnThis retrospective cohort study aimed to determine the predictive relevance of clinical characteristics, additional cytogenetic aberrations, and cKIT and RAS mutations, as well as to evaluate whether specific treatment elements were associated with outcomes in pediatric t(8;21)-positive patients with acute myeloid leukemia (AML).nnnPATIENTS AND METHODSnKaryotypes of 916 pediatric patients with t(8;21)-AML were reviewed for the presence of additional cytogenetic aberrations, and 228 samples were screened for presence of cKIT and RAS mutations. Multivariable regression models were used to assess the relevance of anthracyclines, cytarabine, and etoposide during induction and overall treatment. End points were the probability of achieving complete remission, cumulative incidence of relapse (CIR), probability of event-free survival, and probability of overall survival.nnnRESULTSnOf 838 patients included in final analyses, 92% achieved complete remission. The 5-year overall survival, event-free survival, and CIR were 74%, 58%, and 26%, respectively. cKIT mutations and RAS mutations were not significantly associated with outcome. Patients with deletions of chromosome arm 9q [del(9q); n = 104] had a lower probability of complete remission (P = .01). Gain of chromosome 4 (+4; n = 21) was associated with inferior CIR and survival (P < .01). Anthracycline doses greater than 150 mg/m(2) and etoposide doses greater than 500 mg/m(2) in the first induction course and high-dose cytarabine 3 g/m(2) during induction were associated with better outcomes on various end points. Cumulative doses of cytarabine greater than 30 g/m(2) and etoposide greater than 1,500 mg/m(2) were associated with lower CIR rates and better probability of event-free survival.nnnCONCLUSIONnPediatric patients with t(8;21)-AML and additional del(9q) or additional +4 might not be considered at good risk. Patients with t(8;21)-AML likely benefit from protocols that have high doses of anthracyclines, etoposide, and cytarabine during induction, as well as from protocols comprising cumulative high doses of cytarabine and etoposide.

Heterogeneous cytogenetic subgroups and outcomes in childhood acute megakaryoblastic leukemia: a retrospective international study.

Comprehensive clinical studies of patients with acute megakaryoblastic leukemia (AMKL) are lacking. We performed an international retrospective study on 490 patients (age ≤18 years) with non-Down syndrome de novo AMKL diagnosed from 1989 to 2009. Patients with AMKL (median age 1.53 years) comprised 7.8% of pediatric AML. Five-year event-free (EFS) and overall survival (OS) were 43.7% ± 2.7% and 49.0% ± 2.7%, respectively. Patients diagnosed in 2000 to 2009 were treated with higher cytarabine doses and had better EFS (P = .037) and OS (P = .003) than those diagnosed in 1989 to 1999. Transplantation in first remission did not improve survival. Cytogenetic data were available for 372 (75.9%) patients: hypodiploid (n = 18, 4.8%), normal karyotype (n = 49, 13.2%), pseudodiploid (n = 119, 32.0%), 47 to 50 chromosomes (n = 142, 38.2%), and >50 chromosomes (n = 44, 11.8%). Chromosome gain occurred in 195 of 372 (52.4%) patients: +21 (n = 106, 28.5%), +19 (n = 93, 25.0%), +8 (n = 77, 20.7%). Losses occurred in 65 patients (17.5%): -7 (n = 13, 3.5%). Common structural chromosomal aberrations were t(1;22)(p13;q13) (n = 51, 13.7%) and 11q23 rearrangements (n = 38, 10.2%); t(9;11)(p22;q23) occurred in 21 patients. On the basis of frequency and prognosis, AMKL can be classified to 3 risk groups: good risk-7p abnormalities; poor risk-normal karyotypes, -7, 9p abnormalities including t(9;11)(p22;q23)/MLL-MLLT3, -13/13q-, and -15; and intermediate risk-others including t(1;22)(p13;q13)/OTT-MAL (RBM15-MKL1) and 11q23/MLL except t(9;11). Risk-based innovative therapy is needed to improve patient outcomes.

Changes in cytogenetics and molecular genetics in acute myeloid leukemia from childhood to adult age groups.

To obtain better insight into the biology of acute myeloid leukemia (AML) in various age groups, this study focused on the genetic changes occurring during a lifetime.

Improved outcome of pediatric patients with acute megakaryoblastic leukemia in the AML-BFM 04 trial.

Despite recent advances in the treatment of children with acute megakaryoblastic leukemia (AMKL) using intensified treatment protocols, clear prognostic indicators, and treatment recommendations for this acute myeloid leukemia (AML) subgroup are yet to be defined. Here, we report the outcome of 97 pediatric patients with de novo AMKL (excluding Down syndrome [DS]) enrolled in the prospective multicenter studies AML-BFM 98 and AML-BFM 04 (1998-2014). AMKL occurred in 7.4xa0% of pediatric AML cases, at younger age (median 1.44xa0years) and with lower white blood cell count (mean 16.5u2009×u2009109/L) as compared to other AML subgroups. With 60u2009±u20095xa0%, children with AMKL had a lower 5-year overall survival (5-year OS; vs. 68u2009±u20091xa0%, Plog ranku2009=u20090.038). Yet, we achieved an improved 5-year OS in AML-BFM 04 compared to AML-BFM 98 (70u2009±u20096xa0% vs. 45u2009±u20098xa0%, Plog ranku2009=u20090.041). Allogeneic hematopoietic stem cell transplantation in first remission did not provide a significant survival benefit (5-year OS 70u2009±u200911xa0% vs. 63u2009±u20096xa0%; PMantel-Byaru2009=u20090.85). Cytogenetic data were available for nu2009=u200978 patients. AMKL patients with gain of chromosome 21 had a superior 5-year OS (80u2009±u20099xa0%, Plog ranku2009=u20090.034), whereas translocation t(1;22)(p13;q13) was associated with an inferior 5-year event-free survival (38u2009±u200917xa0%, Plog ranku2009=u20090.04). However, multivariate analysis showed that treatment response (bone marrow morphology on day 15 and 28) was the only independent prognostic marker (RRu2009=u20094.39; 95xa0% CI, 1.97–9.78). Interestingly, GATA1-mutations were detected in six patients (11xa0%) without previously known trisomy 21. Thus, AMKL (excluding DS) remains an AML subgroup with inferior outcome. Nevertheless, with intensive therapy regimens, a steep increase in the survival rates was achieved.

Diagnosis and management of acute myeloid leukemia in children and adolescents

Despite major improvements in outcome over the past decades, acute myeloid leukemia (AML) remains a life-threatening malignancy in children, with current survival rates of ∼70%. State-of-the-art recommendations in adult AML have recently been published in this journal by Döhner et al. The primary goal of an international expert panel of the International BFM Study Group AML Committee was to set standards for the management, diagnosis, response assessment, and treatment in childhood AML. This paper aims to discuss differences between childhood and adult AML, and to highlight recommendations that are specific to children. The particular relevance of new diagnostic and prognostic molecular markers in pediatric AML is presented. The general management of pediatric AML, the management of specific pediatric AML cohorts (such as infants) or subtypes of the disease occurring in children (such as Down syndrome related AML), as well as new therapeutic approaches, and the role of supportive care are discussed.

FLT3 and KIT mutated pediatric acute myeloid leukemia (AML) samples are sensitive in vitro to the tyrosine kinase inhibitor SU11657.

New treatment strategies to improve the outcome of pediatric acute myeloid leukemia (AML) are required as 40% of children diagnosed with AML do not survive. Around 30% of pediatric AML patients harbour a mutation in the tyrosine kinases FLT3 (+/-20%) or KIT (+/-10%). In this study we investigated whether pediatric AML samples (N=61) were sensitive to the tyrosine kinase inhibitor SU11657 (similar to the clinically available drug sunitinib) in vitro, and whether sensitivity was related to expression of, and mutations in, FLT3 and KIT. Overall, SU11657 showed only moderate cytotoxicity. A FLT3 mutation was detected in 35% and a KIT mutation in 8% of the samples. FLT3 and KIT mutated samples were significantly more sensitive to SU11657 than WT KIT and FLT3 samples. Samples without KIT or FLT3 mutations, but with a high wild-type (WT) KIT expression were significantly more sensitive to SU11657 than samples with low KIT expression. Further clinical evaluation of SU11657 and sunitinib combined with chemotherapy would be of interest. Inclusion in clinical trials should not be restricted to patients with FLT3 or KIT mutations.