[The prospects for children with acute lymphoblastic leukemia of being cured has increased in the Czech Republic in the 21st century to 90% - outcome of the ALL-IC BFM 2002 trial]. / Sance na vylécení detí s akutní lymfoblastickou leukémií stoupla v Ceské republicev 21. století na 90 % - výsledky studie ALL IC-BFM 2002.

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most frequent childhood malignancy. Treatment has been unified in the middle of 1980 in the Czech Republic. In 2002-2007 children and adolescents with acute lymphoblastic leukemia were treated in an international randomized trial ALL-IC BFM 2002 in the Czech Republic. 291 patients aged 1-18 years were enrolled; infants below 1 year entered a separate trial. METHODS AND RESULTS: Patients were stratified into three risk groups according to their age, initial leukocyte count, prednisone response, presence of fusion genes BCR/ABL or MLL/AF4, bone marrow D+15 and remission status D+33. The whole therapy took 24 months. Randomized late intensification compared standard BFM therapy with extended, usually more intensive experimental treatment. The median follow-up was 8.7 years. Complete remission was achieved in 97.9% patients, 1% died in remission. 11% of children relapsed, 1.7% with CNS involvement. Six children (2.1%) developed secondary malignancy. Event free survival (EFS) 8 years from diagnosis was 83.5%, overall survival (OS) 91.4%. EFS and OS of the risk groups were: standard risk: 89.4%; 98.1%; intermediate risk: 82.6%; 89.6%; high risk: 68.8%; 78.1%. Male sex and age above 10 years were adverse prognostic factors. CONCLUSIONS: In comparison with the previous trial ALL-BFM 95, significant improvement was achieved.

Intensive chemotherapy for childhood acute lymphoblastic leukemia: results of the randomized intercontinental trial ALL IC-BFM 2002.

PURPOSE: From 2002 to 2007, the International Berlin-Frankfurt-Münster Study Group conducted a prospective randomized clinical trial (ALL IC-BFM 2002) for the management of childhood acute lymphoblastic leukemia (ALL) in 15 countries on three continents. The aim of this trial was to explore the impact of differential delayed intensification (DI) on outcome in all risk groups. PATIENTS AND METHODS: For this trial, 5,060 eligible patients were divided into three risk groups according to age, WBC, early treatment response, and unfavorable genetic aberrations. DI was randomized as follows: standard risk (SR), two 4-week intensive elements (protocol III) versus one 7-week protocol II; intermediate risk (IR), protocol III × 3 versus protocol II × 1; high risk (HR), protocol III × 3 versus either protocol II × 2 (Associazione Italiana Ematologia Oncologia Pediatrica [AIEOP] option), or 3 HR blocks plus single protocol II (Berlin-Frankfurt-Münster [BFM] option). RESULTS: At 5 years, the probabilities of event-free survival and survival were 74% (± 1%) and 82% (± 1%) for all 5,060 eligible patients, 81% and 90% for the SR (n = 1,564), 75% and 83% for the IR (n = 2,650), and 55% and 62% for the HR (n = 846) groups, respectively. No improvement was accomplished by more intense and/or prolonged DI. CONCLUSION: The ALL IC-BFM 2002 trial is a good example of international collaboration in pediatric oncology. A wide platform of countries able to run randomized studies in ALL has been established. Although the alternative DI did not improve outcome compared with standard treatment and the overall results are worse than those achieved by longer established leukemia groups, the national results have generally improved.

Minimal residual disease in peripheral blood at day 15 identifies a subgroup of childhood B-cell precursor acute lymphoblastic leukemia with superior prognosis.

BACKGROUND: Most minimal residual disease-directed treatment interventions in current treatment protocols for acute lymphoblastic leukemia are based on bone marrow testing, which is a consequence of previous studies showing the superiority of bone marrow over peripheral blood as an investigational material. Those studies typically did not explore the prognostic impact of peripheral blood involvement and lacked samples from very early time points of induction. DESIGN AND METHODS: In this study, we employed real-time quantitative polymerase chain reaction analysis to examine minimal residual disease in 398 pairs of blood and bone marrow follow-up samples taken from 95 children with B-cell precursor acute lymphoblastic leukemia treated with the ALL IC-BFM 2002 protocol. RESULTS: We confirmed the previously published poor correlation between minimal residual disease in blood and marrow at early treatment time points, with levels in bone marrow being higher than in blood in most samples (median 7.9-fold, range 0.04-8,293-fold). A greater involvement of peripheral blood at diagnosis was associated with a higher white blood cell count at diagnosis (P=0.003) and with enlargement of the spleen (P=0.0004) and liver (P=0.05). At day 15, a level of minimal residual disease in blood lower than 10(-4) was associated with an excellent 5-year relapse-free survival in 78 investigated patients (100% versus 69 ± 7%; P=0.0003). Subgroups defined by the level of minimal residual disease in blood at day 15 (high-risk: ≥ 10(-2), intermediate-risk: <10(-2) and ≥ 10(-4), standard-risk: <10(-4)) partially correlated with bone marrow-based stratification described previously, but the risk groups did not match completely. No other time point analyses were predictive of outcome in peripheral blood, except for a weak association at day 8. CONCLUSIONS: Minimal residual disease in peripheral blood at day 15 identified a large group of patients with an excellent prognosis and added prognostic information to the risk stratification based on minimal residual disease at day 33 and week 12.

Prognosis of children with mixed phenotype acute leukemia treated on the basis of consistent immunophenotypic criteria.

BACKGROUND: Mixed phenotype acute leukemia (MPAL) represents a diagnostic and therapeutic dilemma. The European Group for the Immunological Classification of Leukemias (EGIL) scoring system unambiguously defines MPAL expressing aberrant lineage markers. Discussions surrounding it have focused on scoring details, and information is limited regarding its biological, clinical and prognostic significance. The recent World Health Organization classification is simpler and could replace the EGIL scoring system after transformation into unambiguous guidelines. DESIGN AND METHODS: Simple immunophenotypic criteria were used to classify all cases of childhood acute leukemia in order to provide therapy directed against acute lymphoblastic leukemia or acute myeloid leukemia. Prognosis, genotype and immunoglobulin/T-cell receptor gene rearrangement status were analyzed. RESULTS: The incidences of MPAL were 28/582 and 4/107 for children treated with acute lymphoblastic leukemia and acute myeloid leukemia regimens, respectively. In immunophenotypic principal component analysis, MPAL treated as T-cell acute lymphoblastic leukemia clustered between cases of non-mixed T-cell acute lymphoblastic leukemia and acute myeloid leukemia, while other MPAL cases were included in the respective non-mixed B-cell progenitor acute lymphoblastic leukemia or acute myeloid leukemia clusters. Analogously, immunoglobulin/T-cell receptor gene rearrangements followed the expected pattern in patients treated as having acute myeloid leukemia (non-rearranged, 4/4) or as having B-cell progenitor acute lymphoblastic leukemia (rearranged, 20/20), but were missing in 3/5 analyzed cases of MPAL treated as having T-cell acute lymphobastic leukemia. In patients who received acute lymphoblastic leukemia treatment, the 5-year event-free survival of the MPAL cases was worse than that of the non-mixed cases (53+/-10% and 76+/-2% at 5 years, respectively, P=0.0075), with a more pronounced difference among B lineage cases. The small numbers of MPAL cases treated as T-cell acute lymphoblastic leukemia or as acute myeloid leukemia hampered separate statistics. We compared prognosis of all subsets with the prognosis of previously published cohorts. CONCLUSIONS: Simple immunophenotypic criteria are useful for therapy decisions in MPAL. In B lineage leukemia, MPAL confers poorer prognosis. However, our data do not justify a preferential use of current acute myeloid leukemia-based therapy in MPAL.

Identification of mutations in the ribosomal protein L5 (RPL5) and ribosomal protein L11 (RPL11) genes in Czech patients with Diamond-Blackfan anemia.

Diamond-Blackfan anemia (DBA) is a congenital red blood cell aplasia that is usually diagnosed during early infancy. Apart from defects in red blood cell maturation, the disorder is also associated with various physical anomalies in 40% of patients. Mutations in the ribosomal protein (RP) S19 are found in 25% of patients, while mutations in other proteins of the small ribosomal subunit--RPS17 and RPS24--have been found in a fraction of patients. Recently, mutations in RPL5, RPL11, and RPL35a of the large ribosomal subunit have also been reported in several DBA patients. Here, we present the identification of mutations in the RPL5 and RPL11 genes in patients from the Czech DBA Registry. Mutations in RPL5 were identified in eight patients from 6 out of 28 families (21.4%), and mutations in RPL11 in two patients from 2 out of 28 families (7.1%). Interestingly, all 10 patients with either an RPL5 or RPL11 mutation exhibited one or more physical anomalies; specifically, thumb anomalies (flat thenar) were always present, while no such anomaly was observed in seven patients with an RPS19 mutation. Moreover, 9 out of 10 patients with either an RPL5 or RPL11 mutation were born small for gestational age (SGA) compared to 3 out of 7 patients from the RPS19-mutated group. These observations may suggest that mutations, at least in RPL5, seem to generally have more profound impact on fetal development than mutations in RPS19. Since RPL5 and RPL11, together with RPL23, are also involved in the MDM2-mediated p53 pathway regulation, we also screened the RPL23 gene for mutations; however, no mutations were identified.