Ossenkoppele, G.J.

High-dose imatinib versus high-dose imatinib in combination with intermediate-dose cytarabine in patients with first chronic phase myeloid leukemia: a randomized phase III trial of the Dutch-Belgian HOVON study group (Article)

2013-04-10T00:00:00Z

Despite the revolutionary change in the prognosis of chronic myeloid leukemia (CML) patients with the introduction of imatinib, patients with resistant disease still pose a considerable problem. In this multicenter, randomized phase III trial, we investigate whether the combination of high-dose imatinib and intermediate-dose cytarabine compared to high-dose imatinib alone, improves the rate of major molecular response (MMR) in newly diagnosed CML patients. This study was closed prematurely because of declining inclusion due to the introduction of second generation tyrosine kinase inhibitors and only one third of the initially required patients were accrued. One hundred nine patients aged 18-65 years were randomly assigned to either imatinib 800 mg (n = 55) or to imatinib 800 mg in combination with two successive cycles of cytarabine 200 mg/m2for 7 days (n = 54). After a median follow-up of 41 months, 67 % of patients were still on protocol treatment. The MMR rate at 12 months was 56 % in the imatinib arm and 48 % in the combination arm (p = 0.39). Progression-free survival was 96 % after 1 year and 89 % after 4 years. Four-year overall survival was 97 %. Adverse events grades 3 and 4 were more common in the combination arm. The addition of intermediate-dose of cytarabine to imatinib did not improve the MMR rate at 12 months. However, the underpowering of the study precludes any definitive conclusions. This trial is registered at www.trialregister.nl (NTR674).

Prognostic impact of white blood cell count in intermediate risk acute myeloid leukemia: Relevance of mutated NPM1 and FLT3-ITD (Article)

2011-09-01T00:00:00Z

Background: High white blood cell count at presentation is an unfavorable prognostic factor for treatment outcome in intermediate cytogenetic risk acute myeloid leukemia. Since the impact of white blood cell count on outcome of subgroups defined by the molecular markers NPMc+and FLT3- internal tandem duplication (ITD) is unknown, we addressed this issue. Design and Methods: We studied the effect of white blood cell count on outcome in a clinically and molecularly welldefined cohort of 525 patients with acute myeloid leukemia using these molecular markers. In addition, since an increased white blood cell count has been associated with an increased FLT3- ITD/FLT3 (wild-type) ratio, we investigated whether the effect of white blood cell count on outcome could be explained by the FLT3-ITD/FLT3 ratio. Results: This analysis revealed that white blood cell count had no impact on outcome in patients with the genotypic combinations 'NPMc+without FLT3-ITD' and 'NPM1 wild-type with or without FLT3-ITD'. In contrast, white blood cell count had a significant impact on complete remission rate (P=0.034), event-free survival (P=0.009) and overall survival (P<0.001) in patients with the genotypic combination 'NPMc+with FLT3-ITD'. A FLT3-ITD/FLT3 ratio greater than 1 was also associated with a reduced complete remission rate (P=0.066) and significantly reduced eventfree survival (P= 0.001) and overall survival (P=0.001) in patients with the genotypic combination 'NPMc+with FLT3-ITD'. Multivariable analysis revealed that white blood cell count and FLT3-ITD/FLT3 ratio were independent prognostic indicators for outcome in the subgroup with the genotypic combination 'NPMc+with FLT3-ITD'. Conclusions: Our results demonstrate that both high white blood cell count and FLT3-ITD/FLT3 ratio are prognostic factors in patients with acute myeloid leukemia with the genotypic combination 'NPMc+with FLT3-ITD'.

Intensified chemotherapy inspired by a pediatric regimen combined with allogeneic transplantation in adult patients with acute lymphoblastic leukemia up to the age of 40 (Article)

2011-06-07T00:00:00Z

Event-free survival (EFS) at 5 years in pediatric acute lymphoblastic leukemia (ALL) is >80%. Outcome in adult ALL is still unsatisfactory, which is due to less cumulative dosing of chemotherapy and less strict adherence to timing of successive cycles. In the present phase II trial, we evaluated a pediatric regimen in adult patients with ALL under the age of 40. Treatment was according to the pediatric FRALLE approach for high-risk ALL patients and characterized by increased dosages of asparaginase, steroids, methotrexate and vincristin. However, allogeneic stem cell transplantation was offered to standard risk patients with a sibling donor and to all high-risk patients in contrast to the pediatric protocol. Feasibility was defined by achieving complete remission (CR) and completion of treatment within a strict timeframe in at least 60% of patients. In all, 54 patients were included with a median age of 26. CR was achieved in 49 patients (91%), of whom 33 completed treatment as scheduled (61%). Side effects primarily consisted of infections and occurred in 40% of patients. With a median follow-up of 32 months, EFS estimated 66% at 24 months and overall survival 72%. These data show that a dose-intensive pediatric regimen is feasible in adult ALL patients up to the age of 40.Leukemia advance online publication, 7 June 2011; doi:10.1038/leu.2011.141.

Role of immune responses in the pathogenesis of low-risk MDS and high-risk MDS: Implications for immunotherapy (Article)

2011-06-01T00:00:00Z

The myelodysplastic syndromes (MDS) constitute a group of heterogeneous clonal haemopoietic stem cell disorders, characterized by ineffective and dysplastic haematopoiesis with varying degrees of peripheral cytopenia. Low-risk MDS is characterized by increased apoptosis in the bone marrow (BM) with autoimmune characteristics whereas the advanced or high-risk stages involve immune evasion and secondary DNA damage, giving cells growth potential to progress into acute myeloid leukaemia (AML). Nevertheless, the causes of MDS remain poorly defined and it is not clear how the disease progresses from an early stage to advanced MDS and AML. Although there are clear indications for a role of the immune system, the exact mechanism by which the immune response contributes to the progression is not yet clear. New insights into the pathophysiology of MDS with regard to the immune system will be instrumental for the development of novel patient-oriented therapies. This review is focused on the role of immune responses in MDS and the implications for the development of novel immune therapies.

Cytarabine dose for acute myeloid leukemia (Article)

2011-03-17T00:00:00Z

BACKGROUND: Cytarabine (ara-C) is an important drug in the treatment of acute myeloid leukemia (AML). High-dose cytarabine (2000 to 3000 mg per square meter of body-surface area) is toxic but results in higher rates of relapse-free survival than does the conventional dose of 100 to 400 mg per square meter. Intermediate dose levels have not been thoroughly evaluated. METHODS: We compared two induction regimens in patients 18 to 60 years of age (median, 49) who had newly diagnosed AML. The intermediate-dose group, totaling 431 patients, received cytarabine at a dose of 200 mg per square meter given by continuous intravenous infusion for 24 hours during cycle 1 of induction therapy and 1000 mg per square meter by infusion for 3 hours twice daily during cycle 2 of induction therapy. The high-dose group, totaling 429 patients, received a dose-escalated regimen of 1000 mg of cytarabine per square meter every 12 hours in cycle 1 and 2000 mg per square meter twice daily in cycle 2. Patients with a complete response did not receive additional cytarabine but received consolidation therapy in a third cycle of chemotherapy (mitoxantrone-etoposide) or underwent autologous or allogeneic stem-cell transplantation. Complete remission rates, survival rates, and toxic effects were assessed for each treatment group. RESULTS: At a median follow-up of 5 years, no significant differences were noted between the intermediate-dose group and the high-dose group with respect to complete remission rates (80% and 82%, respectively), probability of relapse, event-free survival at 5 years (34% and 35%), or overall survival (40% and 42%). High-dose cytarabine provided no clear advantage in any prognostic subgroup. The high-dose treatment resulted in higher incidences of grade 3 and grade 4 toxic effects (in cycle 1), prolonged hospitalization, and delayed neutrophil recovery (in cycle 2) and platelet recovery (in cycles 2 and 3). CONCLUSIONS: Induction therapy with cytarabine at the lower dose already produced maximal antileukemic effects for all response end points, suggesting a plateau in the dose-response relationship above this dose level. High-dose cytarabine results in excessive toxic effects without therapeutic benefit. (Netherlands Trial Register number, NTR230.). Copyright

Polymorphisms in the multidrug resistance gene MDR1 (ABCB1) predict for molecular resistance in patients with newly diagnosed chronic myeloid leukemia receiving high-dose imatinib (Article)

2010-12-23T00:00:00Z

Phase I/II clinical study of Tosedostat, an inhibitor of aminopeptidases, in patients with acute myeloid leukemia and myelodysplasia. (Article)

2010-10-01T00:00:00Z

PURPOSE: To identify the maximum-tolerated dose (MTD) and to evaluate the antileukemic activity of tosedostat (formerly CHR-2797), an orally bioavailable aminopeptidase inhibitor. PATIENTS AND METHODS: In phase I, the MTD of once daily oral doses of tosedostat in hematologic malignancies was defined. In phase II, the therapeutic activity of the maximum-acceptable dose (MAD) of tosedostat was evaluated in elderly and/or relapsing patients with acute myeloid leukemia (AML) or myelodysplastic syndrome. RESULTS: In phase I, 16 patients were treated in four cohorts with tosedostat (60 mg to 180 mg) for 28 days. Three patients reported dose-limiting toxicities: two with reversible thrombocytopenia (> 75% reduction in platelet count) at 180 mg (MTD) and one with a Common Toxicity Criteria (CTC) grade 3 ALT elevation at 130 mg (MAD). In phase II, 41 patients were treated with 130 mg tosedostat. In phases I and II, the most common severe (CTC grades 3 to 5) adverse event was a reduction in the platelet count. Of the 51 AML patients in this study, seven reached complete marrow response (< 5% marrow blasts), with three achieving complete remission, and a further seven patients reaching a partial marrow response (between 5% and 15% marrow blasts). The overall response rate was therefore 27%. All responders were age > 60 years, and 79% had either relapsed or refractory AML. CONCLUSION: This phase I/II study demonstrates that oral once daily dosing with 130 mg tosedostat is well tolerated and has significant antileukemic activity. The favorable risk-benefit profile suggests that further clinical trials are warranted.

Risk-adapted treatment of acute promyelocytic leukemia based on all-trans retinoic acid and anthracycline with addition of cytarabine in consolidation therapy for high-risk patients: Further improvements in treatment outcome (Article)

2010-06-24T00:00:00Z

A risk-adapted strategy based on all-trans retinoic acid (ATRA) and anthracycline monochemotherapy (PETHEMALPA99 trial) has demonstrated a high antileukemic efficacy in acute promyelocytic leukemia. We designed a new trial (LPA2005) with the objective of achieving stepwise improvements in outcome. Between July 2005 and April 2009, low- and intermediate-risk patients (leukocytes < 10 × 109/L) received a reduced dose of mitoxantrone for the second consolidation course, whereas high-risk patients younger than 60 years of age received cytarabine combined with ATRA and idarubicin in the first and third consolidation courses. Of 372 patients attaining complete remission afterATRAplus idarubicin (92.5%), 368 proceeded to consolidation therapy. For low- and intermediate-risk patients, duration of neutropenia and thrombocytopenia and hospital stay were significantly reduced without sacrificing antileukemic efficacy, compared with the previous LPA99 trial. For high-risk patients, the 3-year relapse rate was significantly lower in the LPA2005 trial (11%) than in theLPA99 (26%;P = .03). Overall disease-free survival was also better in the LPA2005 trial (P = .04). In conclusion, the lower dose of mitoxantrone resulted in a significant reduction of toxicity and hospital stay while maintaining the antileukemic activity, and the combination of ATRA, idarubicin, and cytarabine for high-risk acute promyelocytic leukemia significantly reduced the relapse rate in this setting. Registered at http://www.clinicaltrials.gov as NCT00408278.

Efficacy of escalated imatinib combined with cytarabine in newly diagnosed patients with chronic myeloid leukemia (Article)

2010-06-01T00:00:00Z

Abstract. BACKGROUND: In order to improve the molecular response rate and prevent resistance to treatment, combination therapy with different dosages of imatinib and cytarabine was studied in newly diagnosed patients with chronic myeloid leukemia in the HOVON-51 study. DESIGN AND METHODS: Having reported feasibility previously, we hereby report the efficacy of escalated imatinib (200 mg, 400 mg, 600 mg or 800 mg) in combination with two cycles of intravenous cytarabine (200 mg/m(2) or 1000 mg/m(2) days 1 to 7) in 162 patients with chronic myeloid leukemia. RESULTS: With a median follow-up of 55 months, the 5-year cumulative incidences of complete cytogenetic response, major molecular response, and complete molecular response were 89%, 71%, and 53%, respectively. A higher Sokal risk score was inversely associated with complete cytogenetic response (hazard ratio of 0.63; 95% confidence interval, 0.50-0.79, P<0.001). A higher dose of imatinib and a higher dose of cytarabine were associated with increased complete molecular response with hazard ratios of 1.60 (95% confidence interval, 0.96-2.68, P=0.07) and 1.66 (95% confidence interval, 1.02-2.72, P=0.04), respectively. Progression-free survival and overall survival rates at 5 years were 92% and 96%, respectively. Achieving a major molecular response at 1 year was associated with complete absence of progression and a probability of achieving a complete molecular response of 89%. CONCLUSIONS: The addition of intravenous cytarabine to imatinib as upfront therapy for patients with chronic myeloid leukemia is associated with a high rate of complete molecular responses (Clinicaltrials.Gov Identifier: NCT00028847).

Methylation patterns in CD34 positive chronic myeloid leukemia blast crisis cells (Article)

2010-06-01T00:00:00Z

Gemtuzumab ozogamicin as postremission treatment inAMLat 60 years of age or more: results of a multicenter phase 3 study (Article)

2010-04-01T00:00:00Z

Abstract: In older patients with acute myeloid leukemia (AML), the prevention of relapse has remained one of the major therapeutic challenges, with more than 75% relapses after complete remission. The anti-CD33 immunotoxin conjugate gemtuzumab ozogamicin (GO) has shown antileukemic remission induction activity in patients with relapsed AML. Patients with AML or refractory anemia with excess blasts in first complete remission attained after intensive induction chemotherapy were randomized between 3 cycles of GO (6 mg/m(2) every 4 weeks) or no postremission therapy (control) to assess whether GO would improve outcome. The 2 treatment groups (113 patients receiving GO vs 119 control patients) were comparable with regard to age (60-78 years, median 67 years), performance status, and cytogenetics. A total of 110 of 113 received at least 1 cycle of GO, and 65 of 113 patients completed the 3 cycles. Premature discontinuation was mainly attributable to incomplete hematologic recovery or intercurrent relapse. Median time to recovery of platelets 50 x 10(9)/L and neutrophils 0.5 x 10(9)/L after GO was 14 days and 20 days. Nonhematologic toxicities were mild overall, but there was 1 toxic death caused by liver failure. There were no significant differences between both treatment groups with regard to relapse probabilities, nonrelapse mortality, overall survival, or disease-free survival (17% vs 16% at 5 years). Postremission treatment with GO in older AML patients does not provide benefits regarding any clinical end points. The HOVON-43 study is registered at The Netherlands Trial Registry (number NTR212) and at http://www.controlled-trials.com as ISRCTN77039377.

Diagnosis and management of acute myeloid leukemia in adults: Recommendations from an international expert panel, on behalf of the European LeukemiaNet (Article)

2010-01-21T00:00:00Z

In 2003, an international working group last reported on recommendations for diagnosis, response assessment, and treatment outcomes in acute myeloid leukemia (AML). Since that time, considerable progress has been made in elucidating the molecular pathogenesis of the disease that has resulted in the identification of new diagnostic and prognostic markers. Furthermore, therapies are now being developed that target diseaseassociated molecular defects. Recent developments prompted an international expert panel to provide updated evidenceand expert opinion-based recommendations for the diagnosis and management of AML, that contain both minimal requirements for general practice as well as standards for clinical trials. A new standardized reporting system for correlation of cytogenetic and molecular genetic data with clinical data is proposed.

High-dose daunorubicin in older patients with acute myeloid leukemia (Article)

2009-09-24T00:00:00Z

BACKGROUND: A complete remission is essential for prolonging survival in patients with acute myeloid leukemia (AML). Daunorubicin is a cornerstone of the induction regimen, but the optimal dose is unknown. In older patients, it is usual to give daunorubicin at a dose of 45 to 50 mg per square meter of body-surface area. METHODS: Patients in whom AML or high-risk refractory anemia had been newly diagnosed and who were 60 to 83 years of age (median, 67) were randomly assigned to receive cytarabine, at a dose of 200 mg per square meter by continuous infusion for 7 days, plus daunorubicin for 3 days, either at the conventional dose of 45 mg per square meter (411 patients) or at an escalated dose of 90 mg per square meter (402 patients); this treatment was followed by a second cycle of cytarabine at a dose of 1000 mg per square meter for 6 days. The primary end point was event-free survival. RESULTS: The complete remission rates were 64% in the group that received the escalated dose of daunorubicin and 54% in the group that received the conventional dose (P = 0.002); the rates of remission after the first cycle of induction treatment were 52% and 35%, respectively (P<0.001). There was no significant difference between the two groups in the incidence of hematologic toxic effects, 30-day mortality (11% and 12% in the two groups, respectively), or the incidence of moderate, severe, or life-threatening adverse events (P = 0.08). Survival end points in the two groups did not differ significantly overall, but patients in the escalated-treatment group who were 60 to 65 years of age, as compared with the patients in the same age group who received the conventional dose, had higher rates of complete remission (73% vs. 51%), event-free survival (29% vs. 14%), and overall survival (38% vs. 23%). CONCLUSIONS: In patients with AML who are older than 60 years of age, escalation of the dose of daunorubicin to twice the conventional dose, with the entire dose administered in the first induction cycle, effects a more rapid response and a higher response rate than does the conventional dose, without additional toxic effects. (Current Controlled Trials number, ISRCTN77039377; and Netherlands National Trial Register number, NTR212.) Copyright

Standardization of flow cytometry in myelodysplastic syndromes: Report from the first European LeukemiaNet working conference on flow cytometry in myelodysplastic syndromes (Article)

2009-08-01T00:00:00Z

The myelodysplastic syndromes are a group of clonal hematopoietic stem cell diseases characterized by cytopenia(s), dysplasia in one or more cell lineages and increased risk of evolution to acute myeloid leukemia (AML). Recent advances in immunophenotyping of hematopoietic progenitor and maturing cells in dysplastic bone marrow point to a useful role for multiparameter flow cytometry (FCM) in the diagnosis and prognostication of myelodysplastic syndromes. In March 2008, representatives from 18 European institutes participated in a European LeukemiaNet (ELN) workshop held in Amsterdam as a first step towards standardization of FCM in myelodysplastic syndromes. Consensus was reached regarding standard methods for cell sampling, handling and processing. The group also defined minimal combinations of antibodies to analyze aberrant immunophenotypes and thus dysplasia. Examples are altered numbers of CD34+precursors, aberrant expression of markers on myeloblasts, maturing myeloid cells, monocytes or erythroid precursors and the expression of lineage infidelity markers. When applied in practice, aberrant FCM patterns correlate well with morphology, the subclassification of myelodysplastic syndromes, and prognostic scoring systems. However, the group also concluded that despite strong evidence for an impact of FCM in myelodysplastic syndromes, further (prospective) validation of markers and immunophenotypic patterns are required against control patient groups as well as further standardization in multi-center studies. Standardization of FCM in myelodysplastic syndromes may thus contribute to improved diagnosis and prognostication of myelodysplastic syndromes in the future.

Myeloablative allogeneic versus autologous stem cell transplantation in adult patients with acute lymphoblastic leukemia in first remission: A prospective sibling donor versus no-donor comparison (Article)

2009-02-05T00:00:00Z

While commonly accepted in poor-risk acute lymphoblastic leukemia (ALL), the role of allogeneic hematopoietic stem cell transplantation (allo-SCT) is still disputed in adult patients with standard-risk ALL. We evaluated outcome of patients with ALL in first complete remission (CR1), according to a sibling donor versus no-donor comparison. Eligible patients (433) were entered in 2 consecutive, prospective studies, of whom 288 (67%) were younger than 55 years, in CR1, and eligible to receive consolidation by either an autologous SCT or an allo-SCT. Allo-SCT was performed in 91 of 96 patients with a compatible sibling donor. Cumulative incidences of relapse at 5 years were, respectively, 24 and 55% for patients with a donor versus those without a donor (hazard ratio [HR], 0.37; 0.23-0.60; P < .001). Nonrelapse mortality estimated 16% (± 4) at 5 years after allo-SCT. As a result, disease-free survival (DFS) at 5 years was significantly better in the donor group: 60 versus 42% in the no-donor group (HR: 0.60; 0.41-0.89; P= .01). After risk-group analysis, improved outcome was more pronounced in standard-risk patients with a donor, who experienced an overall survival of 69% at 5 years (P = .05). In conclusion, standard-risk ALL patients with a sibling donor may show favorable survival following SCT, due to both a strong reduction of relapse and a modest nonrelapse mortality. This trial is registered with http://www.trialregister.nl under trial ID NTR228.

High INDO (indoleamine 2,3-dioxygenase) mRNA level in blasts of acute myeloid leukemic patients predicts poor clinical outcome (Article)

2008-12-01T00:00:00Z

Indoleamine 2,3-dioxygenase degrades the amino acid tryptophan which is essential for T cells. Tryptophan depletion causes T-cell cycle arrest and solid tumors that express high levels of indoleamine 2,3-dioxygenase can create immune suppression. Recently, blasts of patients with acute myeloid leukemia were shown to express indoleamine 2,3-dioxygenase. We determined INDO (encoding gene for indoleamine 2,3-dioxygenase) mRNA expression in leukemic blasts of 286 patients with acute myeloid leukemia by gene-expression profiling. Results were validated by quantitative polymerase chain reaction analysis in blasts of an independent cohort of 71 patients. High INDO expression was correlated to significantly shortened overall and relapse-free survival. Correlation of INDO expression to relevant known prognostic factors and survival identified high INDO expression as a strong negative independent predicting variable for overall and relapse-free survival. Inhibition of indoleamine 2,3-dioxygenase expressed by myeloid leukemic blasts may result in breaking immune tolerance and offers new therapeutic options for patients with acute myeloid leukemia.

Dose-finding study of imatinib in combination with intravenous cytarabine: Feasibility in newly diagnosed patients with chronic myeloid leukemia (Article)

2008-03-01T00:00:00Z

The HOVON cooperative study group performed a feasibility study of escalated imatinib and intravenous cytarabine in 165 patients with early chronic-phase chronic myeloid leukemia (CML). Patients received 2 cycles of intravenous cytara- bine (200 mg/m2or 1000 mg/m2days 1-7) in conjunction with imatinib (200 mg, 400 mg, 600 mg, or 800 mg), according to predefined, successive dose levels. All dose levels proved feasible. Seven dose- limiting toxicities (DLTs) were observed in 302 cycles of chemotherapy, which werecaused bystreptococcal bacteremia in 5 cases. Intermediate-dose cytarabine (1000 mg/m2) prolonged time to neutro- phil recovery and platelet recovery compared with a standard dose (200 mg/m2). High-dose imatinib (600 mg or 800 mg) extended the time to platelet recovery compared with a standard dose (400 mg). More infectious complications common toxicity criteria (CTC) grade 3 or 4 were observed after intermediate-dose cytara- bine compared with a standard-dose of cytarabine. Early response data after combination therapy included a complete cy-togenetic response in 48% and a major molecular response in 30% of patients, which increased to 46% major molecular responses at 1 year, including 13% complete molecular responses. We conclude that combination therapy of escalating dosages of imatinib and cytarabine is feasible. This study was registered at www.kankerbestrijding.nl as no. CKTO- 2001-03.

Identification of distinct prognostic subgroups in low- and intermediate-1-risk myelodysplastic syndromes by flow cytometry (Article)

2008-02-12T00:00:00Z

The World Health Organization (WHO) classification contributes to refined classification and prognostication of myelodysplastic syndromes (MDSs). Flow cytometry might add significantly to diagnostic and prognostic criteria. Our analysis of bone marrow samples from 50 patients with MDS showed aberrant expression of differentiation antigens in the myelomonocytic lineage. This also accounted for refractory anemia (RA) with or without ringed sideroblasts (RS), indicating multilineage dysplasia. In 38% of patients, CD34+myeloid blasts expressed CD5, CD7, or CD56. Flow cytometry data were translated into a numerical MDS flow-score. Flow-scores increased significantly from RA with or without RS, refractory cytopenia with multilineage dysplasia (RCMD) with or without RS up to refractory anemia with excess of blasts-1 (RAEB-1) and RAEB-2. No significant differences were observed between WHO cytogenetic subgroups. Flow-scores were highly heterogeneous within International Prognostic Scoring System (IPSS) subgroups. Patients in progression to advanced MDS or acute myeloid leukemia had a significantly higher flow-score compared with non-transfusion-dependent patients. In 60% of patients with transfusion dependency or progressive disease, myeloid blasts expressed CD7 or CD56, in contrast to only 9% of non-transfusion-dependent patients. Moreover, all patients with pure RA with or without RS with aberrant myeloid blasts showed an adverse clinical course. In conclusion, flow cytometry in MDS identified aberrancies in the myelomonocytic lineage not otherwise determined by cytomorphology. In addition, flow cytometry identified patients at risk for transfusion dependency and/or progressive disease independent of known risk groups, which might have impact on treatment decisions and the prognostic scoring system in the near future.

The novel AML stem cell-associated antigen CLL-1 aids in discrimination between normal and leukemic stem cells (Article)

2007-10-01T00:00:00Z

In CD34+acute myeloid leukemia (AML), the malignant stem cells reside in the CD38+compartment. We have shown before that the frequency of such CD34+CD38-cells at diagnosis correlates with minimal residual disease (MRD) frequency after chemotherapy and with survival. Specific targeting of CD34+CD38+cells might thus offer therapeutic options. Previously, we found that C-type lectin-like molecule-1 (CLL-1) has high expression on the whole blast compartment in the majority of AML cases. We now show that CLL-1 expression is also present on the CD34+CD38-stem-cell compartment in AML (77/89 patients). The CD34+CLL-1+population, containing the CD34+CD38-CLL-1+cells, does engraft in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice with outgrowth to CLL-1+blasts. CLL-1 expression was not different between diagnosis and relapse (n = 9). In remission, both CLL-1-normal and CLL-1+malignant CD34+CD38-cells were present. A high CLL-1+fraction was associated with quick relapse. CLL-1 expression is completely absent both on CD34+CD38-cells in normal (n = 11) and in regenerating bone marrow controls (n = 6). This AML stem-cell specificity of the anti-CLL-1 antibody under all conditions of disease and the leukemia-initiating properties of CD34+CLL-1+cells indicate that anti-CLL-1 antibody enables both AML-specific stem-cell detection and possibly antigen-targeting in future.

CD34-related coexpression of MDR1 and BCRP indicates a clinically resistant phenotype in patients with acute myeloid leukemia (AML) of older age (Article)

2007-05-01T00:00:00Z

Clinical resistance to chemotherapy in acute myeloid leukemia (AML) is associated with the expression of the multidrug resistance (MDR) proteins P-glycoprotein, encoded by the MDR1/ABCB1 gene, multidrug resistant-related protein (MRP/ABCC1), the lung resistance-related protein (LRP), or major vault protein (MVP), and the breast cancer resistance protein (BCRP/ABCG2). The clinical value of MDR1, MRP1, LRP/ MVP, and BCRP messenger RNA (mRNA) expression was prospectively studied in 154 newly diagnosed AML patients ≤60 years who were treated in a multicenter, randomized phase 3 trial. Expression of MDR1 and BCRP showed a negative whereas MRP1 and LRP showed a positive correlation with high white blood cell count (respectively, p<0.05, p<0.001,p<0.001 and p<0.001). Higher BCRP mRNA was associated with secondary AML (p<0.05). MDR1 and BCRP mRNA were highly significantly associated (p<0.001), as were MRP1 and LRP mRNA (p<0.001) expression. Univariate regression analyses revealed that CD34 expression, increasing MDR1 mRNA as well as MDR1/BCRP coexpression, were associated with a lower complete response (CR) rate and with worse event-free survival and overall survival. When adjusted for other prognostic actors, only CD34-related MDR1/BCRP coexpression remained significantly associated with a lower CR rate (p=0.03), thereby identifying a clinically resistant subgroup of elderly AML patients.

Intensified 12-week CHOP (I-CHOP) plus G-CSF compared with standard 24-week CHOP (CHOP-21) for patients with intermediate-risk aggressive non-Hodgkin lymphoma: A phase 3 trial of the Dutch-Belgian Hemato-Oncology Cooperative Group (HOVON) (Article)

2007-04-01T00:00:00Z

Optimal dose and timing of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy for aggressive non-Hodgkin lymphoma (NHL) is still an unresolved issue. We assessed whether dose intensifications with cyclophosphamide and doxorubicin might improve outcome in younger patients with intermediate-risk aggressive NHL. Previously untreated patients were assigned to receive either 8 courses of standard CHOP (n = 239) or 6 courses of intensified (I)-CHOP (n = 238). Although there was a tendency in favor of I-CHOP for overall survival (OS), disease-free survival (DFS), and event-free survival (EFS), the differences were not significant. However, although these analyses were not planned, when the intermediate-risk group was divided into low-intermediate- and high-intermediate-risk patients according to the International Prognostic Index (IPI), low-intermediate-risk patients had improved 6-year OS (67% vs 52%; P = .05), DFS (58% vs 45%; P = .06), and EFS (41% vs 30%; P = .21) when they were treated with I-CHOP compared with standard CHOP. On the other hand, high-intermediate-risk patients seem to have no benefit from I-CHOP. Although clinically relevant side effects occurred more often in the I-CHOP arm, treatmen-trelated mortality was similar. These data suggest that I-CHOP might be preferable to standard CHOP in younger patients with low-intermediate-risk aggressive NHL.

High-vs low-dose cytarabine combined with interferon alfa in patients with first chronic phase chronic myeloid leukemia. A prospective randomized phase III study (Article)

2007-02-01T00:00:00Z

A prospective randomized phase III study was performed to evaluate whether intensified cytarabine would induce a higher response rate and longer event-free interval as compared to low-dose cytarabine in chronic myeloid leukemia (CML). One hundred and eighteen patients with CML in early chronic phase entered the study. Twenty-eight out of 32 patients assigned to group A received two cycles of a combination of intensified cytarabine and idarubicin followed by interferon alfa (IFN-α) maintenance, 28 patients in group B received standard treatment by a combination of low-dose cytarabine and IFN-α. Forty-nine patients with a human leukocyte antigen-identical sibling donor proceeded to allogeneic stem cell transplantation (allo-SCT) and nine patients were excluded from the analysis. Hematological response was observed in 97% of the patients in group A vs 86% of the patients in group B during the first year of treatment. In group A, 16 patients (50%) achieved a major cytogenetic response, which compared to seven patients (25%) with a major cytogenetic response in group B. With a median follow-up of 58 months (range 34-76), event-free survival was not significantly different between arms A and B. The estimated 5-year survival rate was 56% in the intensified arm and 77% in the low-dose arm (P=0.05). Recipients of allo-SCT showed a 5-year estimated survival rate of 55%. Although intensified cytarabine induced a higher initial percentage of major and complete cytogenetic responses, responses were not sustained by IFN-α maintenance therapy.

The value of the MDR1 reversal agent PSC-833 in addition to daunorubicin and cytarabine in the treatment of elderly patients with previously untreated acute myeloid leukemia (AML), in relation to MDR1 status at diagnosis (Article)

2005-01-01T00:00:00Z

To determine whether MDR1 reversal by the addition of the P-glycoprotein (P-gp) inhibitor PSC-833 to standard induction chemotherapy would improve event-free survival (EFS), 419 untreated patients with acute myeloid leukemia (AML) aged 60 years and older were randomized to receive 2 induction cycles of daunorubicin and cytarabine with or without PSC-833. Patients in complete remission were then given 1 consolidation cycle without PSC-833. Neither complete response (CR) rate (54% versus 48%; P = .22), 5-year EFS (7% versus 8%; P = .53), disease-free survival (DFS; 13% versus 17%; P = .06) nor overall survival (OS; 10% in both arms; P = .52) were significantly improved in the PSC-833 arm. An integrated P-gp score (IPS) was determined based on P-gp function and P-gp expression in AML cells obtained prior to treatment. A higher IPS was associated with a significantly lower CR rate and worse EFS and OS. There was no significant interaction between IPS and treatment arm with respect to CR rate and survival, indicating also a lack of benefit of PSC-833 in P-gp-positive patients. The role of strategies aimed at inhibitory P-gp and other drug-resistance mechanisms continues to be defined in the treatment of patients with AML.

High EVI1 expression predicts poor survival in acute myeloid leukemia: a study of 319 de novo AML patients (Article)

2003-01-01T00:00:00Z

The proto-oncogene EVI1 encodes a DNA binding protein and is located on chromosome 3q26. The gene is aberrantly expressed in acute myeloid leukemia (AML) patients carrying 3q26 abnormalities. Two mRNAs are transcribed from this locus: EVI1 and a fusion of EVI1 with MDS1 (MDS1-EVI1), a gene located 5' of EVI1. The purpose of this study was to investigate which of the 2 gene products is involved in transformation in human AML. To discriminate between EVI1 and MDS1-EVI1 transcripts, distinct real-time quantitative polymerase chain reaction (PCR) assays were developed. Patients with 3q26 abnormalities often showed high EVI1 and MDS1-EVI1 expression. In a cohort of 319 AML patients, 4 subgroups could be distinguished: EVI1(+) and MDS1-EVI1(-) (6 patients; group I), EVI1(+) and MDS1-EVI1(+) (26 patients; group II), EVI1(-) and MDS1-EVI1(+) (12 patients; group III), and EVI1(-) and MDS1-EVI1(-) (275 patients; group IV). The only 4 patients with a 3q26 aberration belonged to groups I and II. Interestingly, high EVI1 and not MDS1-EVI1 expression was associated with unfavorable karyotypes (eg, -7/7q-) or complex karyotypes. Moreover, a significant correlation was observed between EVI1 expression and 11q23 aberrations (mixed lineage leukemia [MLL] gene involvement). Patients from groups I and II had significantly shorter overall and event-free survival than patients in groups III and IV. Our data demonstrate that high EVI1 expression is an independent poor prognostic marker within the intermediate- risk karyotypic group.