Georg Mann

Molecular response to treatment redefines all prognostic factors in children and adolescents with B-cell precursor acute lymphoblastic leukemia: results in 3184 patients of the AIEOP-BFM ALL 2000 study

The Associazione Italiana di Ematologia Oncologia Pediatrica and the Berlin-Frankfurt-Münster Acute Lymphoblastic Leukemia (AIEOP-BFM ALL 2000) study has for the first time introduced standardized quantitative assessment of minimal residual disease (MRD) based on immunoglobulin and T-cell receptor gene rearrangements as polymerase chain reaction targets (PCR-MRD), at 2 time points (TPs), to stratify patients in a large prospective study. Patients with precursor B (pB) ALL (n = 3184) were considered MRD standard risk (MRD-SR) if MRD was already negative at day 33 (analyzed by 2 markers, with a sensitivity of at least 10(-4)); MRD high risk (MRD-HR) if 10(-3) or more at day 78 and MRD intermediate risk (MRD-IR): others. MRD-SR patients were 42% (1348): 5-year event-free survival (EFS, standard error) is 92.3% (0.9). Fifty-two percent (1647) were MRD-IR: EFS 77.6% (1.3). Six percent of patients (189) were MRD-HR: EFS 50.1% (4.1; P < .001). PCR-MRD discriminated prognosis even on top of white blood cell count, age, early response to prednisone, and genotype. MRD response detected by sensitive quantitative PCR at 2 predefined TPs is highly predictive for relapse in childhood pB-ALL. The study is registered at http://clinicaltrials.gov: NCT00430118 for BFM and NCT00613457 for AIEOP.

A treatment protocol for infants younger than 1 year with acute lymphoblastic leukaemia (Interfant-99): an observational study and a multicentre randomised trial

BACKGROUND Acute lymphoblastic leukaemia in infants younger than 1 year is rare, and infants with the disease have worse outcomes than do older children. We initiated an international study to investigate the effects of a new hybrid treatment protocol with elements designed to treat both acute lymphoblastic leukaemia and acute myeloid leukaemia, and to identify any prognostic factors for outcome in infants. We also did a randomised trial to establish the value of a late intensification course. METHODS Patients aged 0-12 months were enrolled by 17 study groups in 22 countries between 1999 and 2005. Eligible patients were stratified for risk according to their peripheral blood response to a 7-day prednisone prophase, and then given a hybrid regimen based on the standard protocol for acute lymphoblastic leukaemia, with some elements designed for treatment of acute myeloid leukaemia. Before the maintenance phase, a subset of patients in complete remission were randomly assigned to receive either standard treatment or a more intensive chemotherapy course with high-dose cytarabine and methotrexate. The primary outcomes were event-free survival (EFS) for the initial cohort of patients and disease-free survival (DFS) for the patients randomly assigned to a treatment group. Data were analysed on an intention-to-treat basis. This trial was registered with ClinicalTrials.gov, number NCT 00015873, and at controlled-trials.com, number ISRCTN24251487. FINDINGS In the 482 enrolled patients who underwent hybrid treatment, 260 (58%) were in complete remission at a median follow-up of 38 (range 1-78) months, and EFS at 4 years was 47.0% (SE 2.6, 95% CI 41.9-52.1). Of 445 patients in complete remission after 5 weeks of induction treatment, 191 were randomised: 95 patients to receive a late intensification course, and 96 to a control group. At a median follow-up of 42 (range 1-73) months, 60 patients in the treatment group and 57 controls were disease-free. DFS at 4 years did not differ between the two groups (60.9% [SE 5.2] for treatment group vs 57.0% [5.5] for controls; p=0.81). During the intensification phase, of 71 patients randomly assigned to the treatment group, and for whom toxicity data were available, 35 (49%) had infections, 21 (30%) patients had mucositis, 22 (31%) patients had toxic effects on the liver, and 2 (3%) had neurotoxicity. All types of rearrangements in the (mixed lineage leukaemia) MLL gene, very high white blood cell count, age of younger than 6 months, and a poor response to the prednisone prophase were independently associated with inferior outcomes. INTERPRETATION Patients treated with our hybrid protocol, and especially those who responded poorly to prednisone, had higher EFS than most reported outcomes for treatment of infant ALL. Delayed intensification of chemotherapy did not benefit patients.

Risk-Adjusted Therapy of Acute Lymphoblastic Leukemia Can Decrease Treatment Burden and Improve Survival: Treatment Results of 2169 Unselected Pediatric and Adolescent Patients Enrolled in the Trial ALL-BFM 95.

The trial ALL-BFM 95 for treatment of childhood acute lymphoblastic leukemia was designed to reduce acute and long-term toxicity in selected patient groups with favorable prognosis and to improve outcome in poor-risk groups by treatment intensification. These aims were pursued through a stratification strategy using white blood cell count, age, immunophenotype, treatment response, and unfavorable genetic aberrations providing an excellent discrimination of risk groups. Estimated 6-year event-free survival (6y-pEFS) for all 2169 patients was 79.6% (+/- 0.9%). The large standard-risk (SR) group (35% of patients) achieved an excellent 6y-EFS of 89.5% (+/- 1.1%) despite significant reduction of anthracyclines. In the medium-risk (MR) group (53% of patients), 6y-pEFS was 79.7% (+/- 1.2%); no improvement was accomplished by the randomized use of additional intermediate-dose cytarabine after consolidation. Omission of preventive cranial irradiation in non-T-ALL MR patients was possible without significant reduction of EFS, although the incidence of central nervous system relapses increased. In the high-risk (HR) group (12% of patients), intensification of consolidation/reinduction treatment led to considerable improvement over the previous ALL-BFM trials yielding a 6y-pEFS of 49.2% (+/- 3.2%). Compared without previous trial ALL-BFM 90, consistently favorable results in non-HR patients were achieved with significant treatment reduction in the majority of these patients.

Long-term results of five consecutive trials in childhood acute lymphoblastic leukemia performed by the ALL-BFM study group from 1981 to 2000

Between 1981 and 2000, 6609 children (<18 years of age) were treated in five consecutive trials of the Berlin–Frankfurt–Münster (BFM) study group for childhood acute lymphoblastic leukemia (ALL). Patients were treated in up to 82 centers in Germany, Austria and Switzerland. Probability of 10-year event-free survival (EFS) (survival) improved from 65% (77%) in study ALL-BFM 81 to 78% (85%) in ALL-BFM 95. In parallel to relapse reduction, major efforts focused on reducing acute and late toxicity through advanced risk adaptation of treatment. The major findings derived from these ALL-BFM trials were as follows: (1) preventive cranial radiotherapy could be safely reduced to 12 Gy in T-ALL and high-risk (HR) ALL patients, and eliminated in non- HR non-T-ALL patients, if it was replaced by high-dose and intrathecal (IT) MTX; (2) omission of delayed re-intensification severely impaired outcome of low-risk patients; (3) 6-month-less maintenance therapy caused an increase in systemic relapses; (4) slow response to an initial 7-day prednisone window was identified as adverse prognostic factor; (5) condensed induction therapy resulted in significant improvement of outcome; (6) the daunorubicin dose in induction could be safely reduced in low-risk patients and (7) intensification of consolidation/re-intensification treatment led to considerable improvement of outcome in HR patients.

Mutations of JAK2 in acute lymphoblastic leukaemias associated with Down's syndrome

BACKGROUND Children with Downs syndrome have a greatly increased risk of acute megakaryoblastic and acute lymphoblastic leukaemias. Acute megakaryoblastic leukaemia in Downs syndrome is characterised by a somatic mutation in GATA1. Constitutive activation of the JAK/STAT (Janus kinase and signal transducer and activator of transcription) pathway occurs in several haematopoietic malignant diseases. We tested the hypothesis that mutations in JAK2 might be a common molecular event in acute lymphoblastic leukaemia associated with Downs syndrome. METHODS JAK2 DNA mutational analysis was done on diagnostic bone marrow samples obtained from 88 patients with Downs syndrome-associated acute lymphoblastic leukaemia; and 216 patients with sporadic acute lymphoblastic leukaemia, Downs syndrome-associated acute megakaryoblastic leukaemia, and essential thrombocythaemia. Functional consequences of identified mutations were studied in mouse haematopoietic progenitor cells. FINDINGS Somatically acquired JAK2 mutations were identified in 16 (18%) patients with Downs syndrome-associated acute lymphoblastic leukaemia. The only patient with non-Downs syndrome-associated leukaemia but with a JAK2 mutation had an isochromosome 21q. Children with a JAK2 mutation were younger (mean [SE] age 4.5 years [0.86] vs 8.6 years [0.59], p<0.0001) at diagnosis. Five mutant alleles were identified, each affecting a highly conserved arginine residue (R683). These mutations immortalised primary mouse haematopoietic progenitor cells in vitro, and caused constitutive Jak/Stat activation and cytokine-independent growth of BaF3 cells, which was sensitive to pharmacological inhibition with JAK inhibitor I. In modelling studies of the JAK2 pseudokinase domain, R683 was situated in an exposed conserved region separated from the one implicated in myeloproliferative disorders. INTERPRETATION A specific genotype-phenotype association exists between the type of somatic mutation within the JAK2 pseudokinase domain and the development of B-lymphoid or myeloid neoplasms. Somatically acquired R683 JAK2 mutations define a distinct acute lymphoblastic leukaemia subgroup that is uniquely associated with trisomy 21. JAK2 inhibitors could be useful for treatment of this leukaemia. FUNDING Israel Trade Ministry, Israel Science Ministry, Jewish National Fund UK, Sam Waxman Cancer Research Foundation, Israel Science Foundation, Israel Cancer Association, Curtis Katz, Constantiner Institute for Molecular Genetics, German-Israel Foundation, and European Commission FP6 Integrated Project EUROHEAR.

Long-Term Outcome in Children With Relapsed ALL by Risk-Stratified Salvage Therapy: Results of Trial Acute Lymphoblastic Leukemia-Relapse Study of the Berlin-Frankfurt-Münster Group 87

PURPOSE Approximately 20% of children with acute lymphoblastic leukemia (ALL) suffer a relapse, and their prognosis is unfavorable. Between 1987 and 1990, the multicenter trial Acute Lymphoblastic Leukemia-Relapse Study of the Berlin-Frankfurt-Münster Group (ALL-REZ BFM) 87 was conducted to establish a uniform treatment for these children in Germany and Austria. PATIENTS AND METHODS Of 207 registered patients, 183 patients were stratified into three groups according to the protocol: A, early bone marrow (BM) relapse (n = 56); B, late BM relapse (n = 101); C, isolated extramedullary relapse (n = 26). Treatment consisted of risk-adapted alternating short-course multiagent systemic and intrathecal chemotherapy, cranial irradiation, if indicated, and conventional maintenance therapy. Additionally, 24 patients with an exceptionally poor prognosis (early BM or any relapse of T-cell ALL) were treated with individual regimens. In 35 patients, stem-cell transplantation was performed. RESULTS The probability of event-free survival (EFS) and overall survival of all registered patients at 15 years was 0.30 +/- 0.03 and 0.37 +/- 0.03, respectively, with significant differences between the strategic groups (A, 0.18 +/- 0.05 and 0.20 +/- 0.05; B, 0.44 +/- 0.05 and 0.52 +/- 0.05; C, 0.35 +/- 0.09 and 0.42 +/- 0.10). Despite risk-adapted treatment, an early time point of relapse and T-lineage immunophenotype were significant predictors of inferior EFS in uni- and multivariate analyses. CONCLUSION With the ALL-REZ BFM 87 protocol, more than one-third of patients may be regarded as cured from recurrent ALL with second complete remissions lasting more than 10 years. Immunophenotype and time point of relapse are important prognostic factors that allow us to adapt more precisely treatment intensity to individual prognosis in future trials.

Successful treatment strategy for Ki-1 anaplastic large-cell lymphoma of childhood: a prospective analysis of 62 patients enrolled in three consecutive Berlin-Frankfurt-Munster group studies.

PURPOSE To prove prospectively the efficacy of a short-pulse chemotherapy for treatment of Ki-1 anaplastic large-cell lymphoma (ALCL) of childhood. PATIENTS AND METHODS From October 1983 to December 1992, 62 patients (median age, 9.7 years) with newly diagnosed Ki-1 ALCL were enrolled onto Non-Hodgkins Lymphoma-Berlin-Frankfurt-Munster (NHL-BFM) studies 83, 86, and 90. The most frequent immunophenotype was T cell. Ki-1 ALCL differed from other subsets of NHL of childhood by the more frequent involvement of bone, soft tissue, and skin, and by the lack of bone marrow (BM) disease. A 5-day prephase course (prednisone/cyclophosphamide) was followed by two different 5-day courses of chemotherapy: course A consisted of dexamethasone, methotrexate (MTX) 0.5 g/m2 (24-hour infusion), intrathecal chemotherapy, ifosfamide, cytarabine (Ara-C), and etoposide (VP-16); course B consisted of cyclophosphamide and doxorubicin instead of ifosfamide, and Ara-C/VP-16, respectively. Treatment was stratified into three branches. Branch 1 (stage I and stage II resected) received three courses; branch 2 (stage II not resected, stage III), six courses; and branch 3 (stage IV), six intensified courses containing MTX 5 g/m2, and Ara-C 2 g/m2. Local radiotherapy was not performed. RESULTS Four patients failed to enter remission, and one died of infection. Seven patients relapsed within 9 months after diagnosis; two patients had isolated local relapses, but BM and CNS were never involved. Fifty patients have been in first continuous complete remission (CR) for 0.6 to 9.7 years (median, 2.5), and 56 are alive. The probabilities for survival and event-free survival (EFS) at 9 years are 83% +/- 7% (SE) and 81% +/- 5%. Skin involvement was the only negative prognostic parameter. CONCLUSION Short-pulse chemotherapy over 2 to 5 months without local therapy modalities is effective in the treatment of Ki-1 ALCL.

The impact of age and gender on biology, clinical features and treatment outcome of non-Hodgkin lymphoma in childhood and adolescence.

We analysed the impact of age and gender on biology and outcome of 2084 patients diagnosed with non‐Hodgkin lymphoma (NHL) between October 1986 and December 2002 and treated according to the Berlin‐Frankfurt‐Münster (BFM) multicentre protocols NHL‐BFM‐86, ‐90 and ‐95. Median age at diagnosis was 8·0 years for 97 precursor B‐lymphoblastic lymphoma (pB‐LBL) patients, 8·8 years for 335 T‐lymphoblastic lymphoma (T‐LBL) patients, 8·4 years for 1004 Burkitts lymphoma/leukaemia (BL/B‐AL) patients, 11·4 years for 173 diffuse large B‐cell lymphoma (centroblastic subtype) (DLBCL‐CB) patients, 13·2 years for 40 primary mediastinal large B‐cell lymphoma (PMLBL) patients and 10·8 years for 215 anaplastic large‐cell lymphoma (ALCL) patients (P < 0·00001). The male:female ratio was 0·9:1 for pB‐LBL and PMLBL, 1·7:1 for DLBCL‐CB, 1·8:1 for ALCL, 2·5:1 for T‐LBL and 4·5:1 for BL/B‐AL (P < 0·00001). The probability of event‐free survival at 5 years (5‐year pEFS) was 85 ± 1% for all 2084 patients [median follow‐up 5·7 (0·1–15·9) years], and was significantly superior for male T‐LBL and DLBCL‐CB patients. Comparing age‐groups 0–4, 5–9, 10–14 and 15–18 years, pEFS was inferior for the youngest patients only in the pB‐LBL‐ and ALCL‐groups. T‐LBL and DLBCL‐CB adolescent females had worse outcome than younger girls while age had no impact on pEFS for boys. We conclude that the distribution of age and gender differed between NHL‐subtypes. The impact of gender on outcome differed between NHL subgroups. The prognostic impact of age differed not only by NHL‐subtype but also according to gender in some subtypes.

Diagnostic Cerebrospinal Fluid Examination in Children With Acute Lymphoblastic Leukemia: Significance of Low Leukocyte Counts With Blasts or Traumatic Lumbar Puncture

PURPOSE To determine the significance of leukemic blasts or traumatic lumbar puncture (TLP) in diagnostic CSF of children enrolled in the Berlin-Frankfurt-Münster (BFM) Acute Lymphoblastic Leukemia-BFM-95 trial. PATIENTS AND METHODS A total of 2,021 patients were retrospectively evaluated according to initial central nervous system (CNS) status. Patients were classified as follows: CNS1 (CNS negative, n = 1,605), CNS2 (< or = 5 WBC/ micro L CSF with blasts, n = 103), CNS3 (CNS positive, n = 58), TLP+ (TLP with blasts, n = 135), or TLP- (TLP without blasts, n = 111). Patients with CNS2 and TLP+ status were eligible for two additional doses of intrathecal (IT) methotrexate (MTX). CNS3 patients received additional IT MTX and cranial irradiation (18 Gy). RESULTS CNS2, CNS3, and TLP+ groups contained a higher percentage of patients with unfavorable characteristics. Cox regression analysis identified TLP+ and CNS3 status as prognostically significant (CNS3): risk ratio (RR) = 2.3; 95% confidence interval [CI], 1.4 to 3.6; P =.0005; TLP+: RR = 1.5; 95% CI, 1.02 to 2.2; P =.04. Overall 5-year event-free survival (EFS) is 79%, for CNS1 it is 80%, and for TLP- it is 83%. CNS2 patients have an EFS of 80%, but the cumulative incidence of relapses with CNS involvement is higher compared with CNS1 patients (0.10 v 0.04). TLP+ patients have a significantly reduced EFS (73%, P =.003) because of an increased incidence of CNS relapses. CNS3 patients suffer from more systemic and CNS relapses (EFS 50%). CONCLUSION CNS2 patients have the same prognosis as patients with CNS1 status, whereas the EFS of TLP+ patients is inferior to CNS1 but superior to CNS3 patients (P =.001). Both subgroups may have benefitted from additional IT MTX.

High expression of the chemokine receptor CXCR4 predicts extramedullary organ infiltration in childhood acute lymphoblastic leukaemia

Childhood acute lymphoblastic leukaemia (ALL) is a malignancy with the potential to infiltrate the liver, spleen, lymph nodes and brain. Such extramedullary presentation is important for understanding the biology of childhood ALL and also for developing new prognostic parameters. A potential mechanism in the trafficking of leukaemia cells is the interaction of the chemokine receptor CXCR4, which is expressed on ALL cells, and its ligand stromal cell‐derived factor‐1 (SDF‐1), produced by stromal cells in bone marrow and extramedullary organs. Functionality of CXCR4 was demonstrated by a high correlation between cell surface density of CXCR4 and transendothelial migration of leukaemia blasts towards a gradient of SDF‐1 (r = 0·73, P = 0·001). Inhibition of SDF‐1‐induced migration by an anti‐CXCR4 monoclonal antibody (78·33 ± 23·86% inhibition) evidenced the specificity of CXCR4 to SDF‐1. In order to evaluate clinical significance of CXCR4 expression, lymphoblasts from the bone marrow of 73 patients with and without extramedullary organ infiltration were compared. Multiparameter flow cytometry revealed that lymphoblasts from patients with high extramedullary organ infiltration, defined as ultrasonographically measured enlargement of liver or spleen, expressed the CXCR4 receptor at higher fluorescence intensity (median 66·12 ± 66·17) than patients without extramedullary organ infiltration (median 17·56 ± 19·29; P < 0·001). Consequently, high expression of CXCR4 was strongly predictive for extramedullary organ involvement, independently of the peripheral lymphoblast count. Highest CXCR4 expression was seen in mature B ALL (median 102·74 ± 92·13; P < 0·003), a disease characterized by a high incidence of extramedullary bulky disease. As high expression of the chemokine receptor CXCR4 predicts extramedullary organ infiltration in childhood ALL, we suggest that CXCR4 and its ligand play an essential role in extramedullary invasion.