Alloimmunization in transfused patients with constitutional anemias in Norway.

BACKGROUND AND OBJECTIVES: The status of red blood cell alloimmunization in patients with constitutional anemias including hemoglobinopathies is not known in Norway. The study objective was to investigate the impact of a strategy based on phenotype-matching for C, c, E, e, K, Jka, Jkb, Fya, Fyb, S and s on alloimmunization. MATERIALS AND METHODS: We reviewed transfusions of 40 patients retrospectively using the computerized blood bank management system and medical records; including diagnosis, age at start of transfusion therapy, gender, number and age of packed red blood cell units transfused, follow-up time, phenotypes of the donors and patients, antigen-negative patients exposed to antigen-positive packed red blood cell units, transfusion reactions and alloantibody specificities. RESULTS: Forty patients received 5402 packed red blood cell units. Alloimmunization frequency was 20 % for the whole group, being 7%, 25 % and 30 % in patients with sickle cell disease (n = 14), thalassemia (n = 16) and other conditions (n = 10), respectively. The alloantibodies detected were anti-E, -c, -C, -Cw, -K, -Jka and -Lua. CONCLUSION: Good communication between the clinicians and the transfusion services is essential for successful management of patients with constitutional anemias. Providing full phenotype-matched units was not always possible. Extended pheno-/genotyping before the first transfusion and providing antigen-negative units for antigen-negative patients for at least C, c, E and K in every red cell transfusion would probably have reduced the alloimmunization rate. Non-phenotype-matched transfusions seem to be the main reason for alloimmunization. Finding markers for identifying responders prone to alloimmunization will ensure targeted transfusion strategies.

Treatment-related mortality in relapsed childhood acute lymphoblastic leukemia.

BACKGROUND: Treatment of relapsed childhood acute lymphoblastic leukemia (ALL) is particularly challenging due to the high treatment intensity needed to induce and sustain a second remission. To improve results, it is important to understand how treatment-related toxicity impacts survival. PROCEDURE: In this retrospective population-based study, we described the causes of death and estimated the risk for treatment-related mortality in patients with first relapse of childhood ALL in the Nordic Society of Paediatric Haematology and Oncology ALL-92 and ALL-2000 trials. RESULTS: Among the 483 patients who received relapse treatment with curative intent, we identified 52 patients (10.8%) who died of treatment-related causes. Twelve of these died before achieving second remission and 40 died in second remission. Infections were the cause of death in 38 patients (73.1%), predominantly bacterial infections during the chemotherapy phases of the relapse treatment. Viral infections were more common following hematopoietic stem cell transplantation (HSCT) in second remission. Independent risk factors for treatment-related mortality were as follows: high-risk stratification at relapse (hazard ratio [HR] 2.2; 95% confidence interval [CI] 1.3-3.9; P < 0.01), unfavorable cytogenetic aberrations (HR 3.4; 95% CI 1.3-9.2; P = 0.01), and HSCT (HR 4.64; 95% CI 2.17-9.92; P < 0.001). In contrast to previous findings, we did not observe any statistically significant sex or age differences. Interestingly, none of the 17 patients with Down syndrome died of treatment-related causes. CONCLUSIONS: Fatal treatment complications contribute significantly to the poor overall survival after relapse. Implementation of novel therapies with reduced toxicity and aggressive supportive care management are important to improve survival in relapsed childhood ALL.

The effect of central nervous system involvement and irradiation in childhood acute lymphoblastic leukemia: Lessons from the NOPHO ALL-92 and ALL-2000 protocols.

BACKGROUND: Central nervous system irradiation (CNS-RT) has played a central role in the cure of acute lymphoblastic leukemia (ALL), but due to the risk of long-term toxicity, it is now considered a less-favorable method of CNS-directed therapy. PROCEDURES: Retrospectively, we estimated the effect of CNS involvement and CNS-RT on events and overall survival (OS) in 835 children treated for high-risk ALL in the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL-92 and ALL-2000 trials. RESULTS: We did not observe a statistically significant difference in the OS or event-free survival (EFS) in patients with CNS involvement at diagnosis, but the risk of isolated CNS relapse was higher (hazard ratio [HR] 7.09, P < 0.001). CNS-RT was given to 169 of the 783 patients in first complete remission, of which 16 had CNS involvement at diagnosis. In general, CNS-RT improved EFS (HR 0.58, P < 0.05) but not OS (HR 0.69, P = n.s.). The adjusted HRs for all relapses, isolated bone marrow relapse, CNS-involving relapse, and isolated CNS relapse, were 0.47 (P < 0.01), 0.50 (P < 0.05), 0.34 (P < 0.01), and 0.12 (P < 0.01), respectively, in irradiated patients. CONCLUSIONS: CNS-RT was associated with an advantage in EFS by decreasing the risk of relapse but without improving OS.

Relapsed childhood acute lymphoblastic leukemia in the Nordic countries: prognostic factors, treatment and outcome.

Relapse is the main reason for treatment failure in childhood acute lymphoblastic leukemia. Despite improvements in the up-front therapy, survival after relapse is still relatively poor, especially for high-risk relapses. The aims of this study were to assess outcomes following acute lymphoblastic leukemia relapse after common initial Nordic Society of Paediatric Haematology and Oncology protocol treatment; to validate currently used risk stratifications, and identify additional prognostic factors for overall survival. Altogether, 516 of 2735 patients (18.9%) relapsed between 1992 and 2011 and were included in the study. There were no statistically significant differences in outcome between the up-front protocols or between the relapse protocols used, but an improvement over time was observed. The 5-year overall survival for patients relapsing in the period 2002-2011 was 57.5±3.4%, but 44.7±3.2% (P<0.001) if relapse occurred in the period 1992-2001. Factors independently predicting mortality after relapse included short duration of first remission, bone marrow involvement, age ten years or over, unfavorable cytogenetics, and Down syndrome. T-cell immunophenotype was not an independent prognostic factor unless in combination with hyperleukocytosis at diagnosis. The outcome for early combined pre-B relapses was unexpectedly poor (5-year overall survival 38.0±10.6%), which supports the notion that these patients need further risk adjustment. Although survival outcomes have improved over time, the development of novel approaches is urgently needed to increase survival in relapsed childhood acute lymphoblastic leukemia.

Rare MLL-ELL fusion transcripts in childhood acute myeloid leukemia-association with young age and myeloid sarcomas?

BACKGROUND: The chromosomal translocation t(11;19)(q23;p13) with a breakpoint within subband 19p13.1 is found mainly in acute myeloid leukemia (AML) and results in the MLL-ELL fusion gene. Variations in the structure of MLL-ELL seem to influence the leukemogenic potency of the fusion in vivo and may lie behind differences in clinical features. The number of cases reported so far is very limited and the addition of more information about MLL-ELL variants is essential if the possible clinical significance of rare fusions is to be determined. CASE PRESENTATION: Cytogenetic and molecular genetic analyses were done on the bone marrow cells of a 20-month-old boy with an unusual form of myelomonocytic AML with multiple myeloid sarcomas infiltrating bone and soft tissues. The G-banding analysis together with FISH yielded the karyotype 47,XY, +6,t(8;19;11)(q24;p13;q23). FISH analysis also demonstrated that MLL was split. RNA-sequencing showed that the translocation had generated an MLL-ELL chimera in which exon 9 of MLL (nt 4241 in sequence with accession number NM_005933.3) was fused to exon 6 of ELL (nt 817 in sequence with accession number NM_006532.3). RT-PCR together with Sanger sequencing verified the presence of the above-mentioned fusion transcript. CONCLUSIONS: Based on our findings and information on a few previously reported patients, we speculate that young age, myelomonoblastic AML, and the presence of extramedullary disease may be typical of children with rare MLL-ELL fusion transcripts.

A 15-month-old girl with fever and pancytopenia.

A 15 month-old girl was admitted after a couple of months' history of illness with remittent fever, increasing pallor and a swollen abdomen. On admission she was highly febrile, with palpably enlarged liver and spleen. Blood tests revealed pancytopenia, a high CRP level and a high serum ferritin level. We describe the diagnostic evaluation, interpretation and treatment.

Acute respiratory failure in 3 children with juvenile myelomonocytic leukemia.

BACKGROUND: Juvenile myelomonocytic leukemia is a rare hematopoietic stem cell disease in children with features of both myelodysplasia and myeloproliferation. Extramedullary involvement has been reported and pulmonary involvement secondary to leukemic infiltration is an initial manifestation, which may result in acute respiratory failure. OBSERVATION: We present 3 children with juvenile myelomonocytic leukemia and suspected pulmonary leukemic cell infiltration who all also suffered from respiratory insufficiency. The differential diagnosis included asthma and infections. CONCLUSIONS: In each case the patients improved rapidly after initiation of antileukemic treatment including 6-mercaptopurine or cytarabine.

H1N1 infection in children with haematological and oncological diseases in Norway.

AIM: To describe the impact of H1N1 infections in children with haematological and oncological diseases during the 2009 H1N1 pandemics. METHODS: A short questionnaire was e-mailed to all paediatric departments taking care of patients with oncological and chronic haematological diseases, asking for known cases of H1N1 infections in this patient group. RESULTS: Nine children treated for cancer and seven children with haematological diseases were registered. No death occurred, but two patients treated for cancer (acute lymphoblastic leukaemia at diagnosis, acute myeloid leukaemia in chemotherapy-induced bone marrow aplasia) experienced life-threatening respiratory complications. CONCLUSION: In all patients with haematological disease and most cases of oncological diseases, the infections ran a mild course. However, life-threatening complications occurred in severely immunosuppressed and neutropenic patients. Delay of anticancer treatment is a concern even in mild cases.

High white blood cell count at diagnosis of childhood acute lymphoblastic leukaemia: biological background and prognostic impact. Results from the NOPHO ALL-92 and ALL-2000 studies.

Prognostic impact of peripheral blood white blood cell count (WBC) at the diagnosis of childhood acute lymphoblastic leukaemia (ALL) was evaluated in a population-based consecutive series of 2666 children aged 1-15 treated for ALL between 1992 and 2008 in the five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden). Ten-year event-free (pEFS(10 y)) survival and overall (pOS(10 y)) survival were 0.75 ± 0.01 and 0.85 ± 0.01, respectively. Although treatment intensity was determined by WBC, non-remission and relapsed patients still had significantly higher WBC than those in remission for B-cell precursor (BCP) (median WBC: 24.8 vs. 14.0 vs. 8.3 × 10(9) /L, P < 0.001), but not for T-lineage (T-ALL) (median WBC: 127.8 vs. 113.0 vs. 86.8 × 10(9) /L, P = 0.22). pEFS was inversely related to WBC for BCP (P < 0.001), but not for T-ALL. WBC was not associated with risk of event for BCP or T-ALL for patients with minimal residual disease at the end of induction (MRD(d29) ) <10(-3). In contrast, for MRD(d29) ≥ 10(-3) and <5% leukaemic blasts in bone marrow at day 29, the pEFS(5 y) for WBC < 100.0 (N = 152) vs. ≥ 100.0 (N = 19) was 0.76 vs. 0.50 (P = 0.001). That was the case both for BCP (pEFS(5 y) 0.76 vs. 0.58) and for T-ALL (pEFS(5 y) 0.71 vs. 0.38). Whether the inferior EFS for the subset of patients with high WBC and slow initial response to treatment reflects rare or overlooked cytogenetic aberrations as well as the factors that determine WBC levels at diagnosis awaits exploration.

Striking decrease in the total precursor B-cell compartment during early childhood as evidenced by flow cytometry and gene expression changes.

The number of circulating B-cells in peripheral blood plateaus between 2 and 24 months of age, and thereafter declines gradually. How this reflects the kinetics of the precursor B-cell pool in the bone marrow is of clinical interest, but has not been studied thoroughly in humans. The authors analyzed bone marrow (n = 37) from healthy children and adults (flow cytometry) searching for age-related changes in the total precursor B-cell compartment. In an age-matched cohort (n = 25) they examined age-related global gene expression changes (Affymetrix) in unsorted bone marrow with special reference to the recombination activating gene 1, RAG1. Subsequently, they searched the entire gene set for transcripts correlating to the RAG1 profile to discover other known and possibly new precursor B-cell related transcripts. Both methods disclosed a marked, transient increase of total precursor B-cells at 6-20 months, followed by a rapid decrease confined to the first 2 years. The decline thereafter was considerably slower, but continued until adulthood. The relative composition of total precursor B-cells, however, did not change significantly with age. The authors identified 54 genes that were highly correlated to the RAG1 profile (r >or= .9, p < 1 x 10(-8)). Of these 54 genes, 15 were characteristically B-lineage associated like CD19, CD79, VPREB, EBF1, and PAX5; the remaining 39 previously not described as distinctively B-lineage related. The marked, transient increase in precursor B-cells and RAG1 transcriptional activity is not reflected by a similar peak in B-cells in peripheral blood, whereas the sustained plateau concurs in time.

Thioguanine pharmacokinetics in induction therapy of children with acute myeloid leukemia.

We studied the pharmacokinetics of 6-thioguanine (6TG) in 50 children treated for newly diagnosed acute myeloid leukemia, four of them with Down syndrome (DS). They received oral 6TG 100 mg/m2 body surface area twice daily for 4 days. Etoposide, 100 mg/m2/24 h, and cytarabine, 200 mg/m2/24 h, were administered concomitantly by intravenous infusion. On day 5, doxorubicin 75 mg/m2 was given as an 8-h infusion. The concentration of thioguanine nucleotides (TGN) in erythrocytes, the active metabolites of 6TG, was determined by high-performance liquid chromatography. The mean TGN concentration from 72, 95, and 106-h samples was used as a measure of drug exposure for each individual. The median TGN concentration in non-DS children above 2 years of age was 2.30 micromol/mmol Hb (range 0.57-25.3). The TGN concentrations varied widely (30-fold) also after dose normalization. We found no correlation with demographic, clinical, or biochemical parameters, and differences in bioavailability might be the most important explanation to interpatient variability. Children with high TGN concentration tended to have longer treatment interval to the next course, but we found no correlation with our predefined parameters for clinical response, that is, remission and relapse rate. Therefore, 6TG does not seem to be a candidate for therapeutic drug monitoring by TGN measurement, at least not in the setting of short multidrug treatment courses. Children with DS had significantly higher TGN concentrations, indicating that dose reduction might be considered to reach the same drug exposure as in non-DS children.

[Childhood acute lymphoblastic leukemia in Norway 1992-2000]. / Akutt lymfatisk leukemi hos barn i Norge 1992-2000.

BACKGROUND: Acute lymphoblastic leukemia is the most common malignancy in childhood. The survival rate has increased steadily over the last 40 years. MATERIAL AND METHODS: All children aged 0-15 years and diagnosed in Norway in the period 1992-2000, were included in the study (n = 301). The patients were followed up until 1.1. 2005. RESULTS AND INTERPRETATION: The diagnosis was made in 301 children, 33 new cases per year (range 24 to 40) on average. The peak incidence was between 2 and 5 years. Four of 6 infants with acute lymphoblastic leukemia and all 4 with mature B-cell leukemia are alive. Two of the remaining 291 children died before treatment was started. 289 were all treated according to the common Nordic NOPHO-ALL 1992 protocol. All children achieved remission (99.7%), except for one who died before remission was achieved. 55 children (19%) relapsed. Radiation to the brain as part of central nervous system prophylaxis was given to just 10% of the children. The 10-year event-free survival (p-EFS) was 76%, and 244 of 289 (84%) were alive 4-13 years after the diagnosis was made. The data are comparable with the best international results.

Etoposide pharmacokinetics in children treated for acute myeloid leukemia.

We studied the pharmacokinetics of etoposide in 45 children treated for newly diagnosed acute myeloid leukemia. Etoposide, 100 mg/m body surface area/24 h, was administered by 96-h continuous intravenous infusion. Concomitantly, the children received cytarabine 200 mg/m/24 h by intravenous infusion and 6-thioguanine 100 mg/m twice daily orally. Median total body clearance in children 0.5-1.8 (n=4) and 2.3-17.7 years old (n=36) without Down's syndrome was 17.1 and 17.6 ml/min/m, respectively (P=0.96). Five children with Down's syndrome had a median clearance of 13.6 ml/min/m (P=0.067 compared with non-Down's syndrome children). Eighteen of the children received a second identical treatment course 3-4 weeks later; there was a significant correlation between individual clearance values (rho=0.56; P=0.017). We found no significant correlation between etoposide pharmacokinetics and the remission rate or the relapse rate. In conclusion, our findings indicate that special dose-calculation guidelines for infants above 3 months old are not substantiated by age-dependent pharmacokinetics of etoposide. Down's syndrome children might be candidates for dose reduction if our data are confirmed in larger numbers of patients. Low course-to-course variability indicates that pharmacokinetically guided dosing of etoposide might be clinically relevant, if larger studies can demonstrate that this approach decreases toxicity or increases response rates.

Doxorubicin pharmacokinetics is correlated to the effect of induction therapy in children with acute myeloid leukemia.

We studied the pharmacokinetics of doxorubicin in 41 children treated for newly diagnosed acute myeloid leukemia. Doxorubicin, 75 mg/m2 body surface area, was administered by constant i.v. infusion over 8 h. Four children with Down's syndrome (DS), 1.2-2.3 years old, had a median total body clearance of 523 ml/min/m2. The median clearance in non-DS children, 0.6-1.8 years old (n = 4) and 2.5-17.7 years old (n = 33), was 446 and 538 ml/min/m2, respectively. Patients who went into complete remission (CR) after induction therapy had a significantly higher median plasma concentration of doxorubicin than those who did not, 249 compared with 180 ng/ml, respectively (P = 0.036; analysis restricted to non-DS patients). Doxorubicin plasma concentration was an independent factor for CR, both in univariate (P = 0.031) and multivariate analysis including sex, age and white blood cell count at diagnosis (P = 0.021). Patients who reached CR had a significantly lower doxorubicin clearance than those who did not, 513 and 657 ml/min/m2, respectively (P = 0.017). In conclusion, doxorubicin plasma concentration and total body clearance during up-front treatment were correlated to the effect of induction therapy. Prospective studies should be performed to confirm the concentration-effect relationship and explore the possibility of therapeutic monitoring.

Translocation t(12;21) is related to in vitro cellular drug sensitivity to doxorubicin and etoposide in childhood acute lymphoblastic leukemia.

The t(12;21) (p13;q22) translocation resulting in ETV6/RUNX1 (previously named TEL/AML1) gene fusion is present in about 25% of children with precursor B-lineage acute lymphoblastic leukemia (B-ALL). We successfully tested 275 precursor B-ALL samples from children aged 1 to 17 years to determine the relation between t(12;21) and in vitro cellular drug resistance, measured by the fluorometric microculture cytotoxicity assay (FMCA). Samples from 83 patients (30%) were positive for t(12;21). The ETV6/RUNX1(+) samples were significantly more sensitive than ETV6/RUNX1(-) samples to doxorubicin, etoposide, amsacrine, and dexamethasone, whereas the opposite was true for cytarabine. After matching for unevenly distributed patient characteristics, that is, excluding patients with high hyperdiploidy (> 51 chromosomes), t(9; 22), t(1;19), or 11q23 rearrangement, the ETV6/RUNX1(+) samples remained significantly more sensitive to doxorubicin (P = .001) and etoposide (P = .001). For the other drugs tested (amsacrine, cytarabine, dexamethasone, prednisolone, vincristine, 6-thioguanine, and 4-hydroperoxy-cyclophosphamide), no significant difference in cellular drug sensitivity was found. In conclusion, we found that the presence of the t(12;21) translocation in childhood precursor B-ALL is associated with a high tumor cell sensitivity to doxorubicin and etoposide. High throughput techniques should now be used to elucidate the cellular mechanisms by which ETV6/RUNX1 gene fusion is linked to increased sensitivity to these drugs.

Methotrexate infusions as central nervous system prophylaxis in children with acute lymphocytic leukemia: the Norwegian experience.

This study included all 690 children in Norway diagnosed as having acute lymphocytic leukemia (ALL) from July 1975 till the end of 1997. Relapses and deaths were monitored until the end of 2000. Neuroleukemia prophylaxis was intravenous methotrexate (MTX) infusions as intermediate-dose methotrexate (IDM) or high-dose methotrexate (HDM) combined with intrathecal MTX. From 1992, systemic therapy was considerably intensified, and, in addition, patients in a subgroup of the high-risk and very high-risk groups were given prophylactic cranial irradiation. The overall findings showed that MTX significantly reduced central nervous system (CNS)-related relapses, and, in general, reinforced systemic therapy reduced significantly non-CNS relapses and deaths. The overall crude survival was 75%. During the study period, the crude survival improved for patients on standard protocols from initially 65 to 90%. Forty patients (6%) developed isolated CNS relapse, 27 (4%) had combined CNS relapse, whereas 180 (26%) had non-CNS relapse. When IDM and HDM were compared, the cumulative risk for isolated CNS relapse was significantly lower with HDM, 12 and 5%, respectively. For any relapses that involved the CNS, the risk remained significantly lower for HDM, 8 versus 18%. Of the 40 patients with isolated CNS relapse, 23 survived (58%).