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Dive into the research topics where Leo F. Verdonck is active.

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Featured researches published by Leo F. Verdonck.


The New England Journal of Medicine | 2009

High-dose daunorubicin in older patients with acute myeloid leukemia

Bob Löwenberg; Gert J. Ossenkoppele; Wim L.J. van Putten; Harry C. Schouten; Carlos Graux; Augustin Ferrant; Pieter Sonneveld; Johan Maertens; Mojca Jongen-Lavrencic; Marie von Lilienfeld-Toal; Bart J. Biemond; Edo Vellenga; Marinus van Marwijk Kooy; Leo F. Verdonck; Joachim Beck; Hartmut Döhner; Alois Gratwohl; Thomas Pabst; Gregor Verhoef

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 every 12 hours [DOSAGE ERROR CORRECTED] 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.)


The New England Journal of Medicine | 1991

Allogeneic bone marrow transplantation in multiple myeloma

Gösta Gahrton; Sante Tura; Per Ljungman; Coralie Belanger; Lena Brandt; Michele Cavo; Thierry Facon; Alberto Granena; Martin Gore; Alois Gratwohl; Bob Löwenberg; Jukka Nikoskelainen; Josy Reiffers; Diana Samson; Leo F. Verdonck; Liisa Volin

Abstract Background and Methods. In contrast to autologous bone marrow transplants for hematologic cancers, allogeneic transplants contain no tumor cells that might cause a relapse. We report the results of such allogeneic bone marrow transplantation using HLA-compatible sibling donors in 90 patients with multiple myeloma performed in 26 European centers between 1983 and 1989. Results. At the time of the most recent follow-up, 79 months after the start of the study, 47 patients were alive and 43 were dead. The rate of complete remission after bone marrow transplantation was 43 percent for all patients and 58 percent for the patients who had engraftment. The actuarial survival at 76 months was 40 percent. The median duration of relapse-free survival among patients who were in complete remission after bone marrow transplantation was 48 months. The stage of the disease at diagnosis and the number of treatment regimens tried before bone marrow transplantation were predictive of the likelihood of complete remi...


British Journal of Haematology | 2001

Progress in allogeneic bone marrow and peripheral blood stem cell transplantation for multiple myeloma : a comparison between transplants performed 1983-93 and 1994-98 at European Group for Blood and Marrow Transplantation centres

Gösta Gahrton; H. Svensson; Michele Cavo; J. Apperley; A. Bacigalupo; Bo Björkstrand; Joan Bladé; J.J.L.M. Cornelissen; A. de Laurenzi; Thierry Facon; Per Ljungman; Mauricette Michallet; D. Niederwieser; R. Powles; Josy Reiffers; N.H. Russell; D. Samson; U.W. Schaefer; A.V.M.B. Schattenberg; Sante Tura; Leo F. Verdonck; Jean-Paul Vernant; R. Willemze; Liisa Volin

Out of 690 allogeneic matched sibling donor transplants for multiple myeloma reported to the European Group for Blood and Marrow Transplantation (EBMT) registry, 334 were performed during the period 1983–93 (all with bone marrow) and 356 during 1994–98 [223 with bone marrow and 133 with peripheral blood stem cells (PBSCs)]. The median overall survival was 10 months for patients transplanted during the earlier time period and 50 months for patients transplanted with bone marrow during the later period. The use of PBSCs was associated with earlier engraftment but no significant survival benefit compared to bone marrow transplants during the same time period. The improvement in survival since 1994 was the result of a significant reduction in transplant‐related mortality, which was 38%, 21% and 25% at 6 months and 46%, 30% and 37% at 2 years during the earlier period, and the later period with bone marrow and PBSCs respectively. Reasons for the reduced transplant‐related mortality appeared to be fewer deaths owing to bacterial and fungal infections and interstitial pneumonitis, in turn a result of earlier transplantation and less prior chemotherapy. Better supportive treatment and more frequent use of cytokines may also play a role. The improvement in survival was not directly related to the increased use of PBSCs.


Journal of Clinical Oncology | 2005

Prognostic index for adult patients with acute myeloid leukemia in first relapse

Dimitri A. Breems; Wim L.J. van Putten; Peter C. Huijgens; Gert J. Ossenkoppele; Gregor Verhoef; Leo F. Verdonck; Edo Vellenga; Georgine E. de Greef; Emanuel Jacky; Johannes Van der Lelie; Marc Boogaerts; Bob Löwenberg

PURPOSE The treatment of acute myeloid leukemia (AML) in first relapse is associated with unsatisfactory rates of complete responses that usually are short lived. Therefore, a clinically useful prognostic index can facilitate therapeutic decision making and evaluation of investigational treatment strategies at relapse of AML. PATIENTS AND METHODS A prognostic score is presented based on the multivariate analysis of 667 AML patients in first relapse among 1,540 newly diagnosed non-M3 AML patients (age 15 to 60 years) entered onto three successive Dutch-Belgian Hemato-Oncology Cooperative Group and the Swiss Group for Clinical Cancer Research Collaborative Group trials. RESULTS Four clinically relevant parameters are included in this index (ie, length of relapse-free interval after first complete remission, cytogenetics at diagnosis, age at relapse, and whether previous stem-cell transplantation was performed). Using this stratification system, three risk groups were defined: a favorable prognostic group A (overall survival [OS] of 70% at 1 year and 46% at 5 years), an intermediate-risk group B (OS of 49% at 1 year and 18% at 5 years), and a poor-risk group C (OS of 16% at 1 year and 4% at 5 years). CONCLUSION The prognostic index estimates the outcome of AML patients in first relapse using four commonly applied clinical parameters and might identify patients who are candidates for salvage and investigational therapy.


The New England Journal of Medicine | 1995

Comparison of CHOP chemotherapy with autologous bone marrow transplantation for slowly responding patients with aggressive non-Hodgkin's lymphoma

Leo F. Verdonck; Wim L.J. van Putten; Anton Hagenbeek; Harry C. Schouten; Pieter Sonneveld; Gustaaf W. van Imhoff; Hanneke C. Kluin-Nelemans; John Raemaekers; Rien H.J. van Oers; Hans L. Haak; Rik Schots; A. W. Dekker; Gijsbert C. de Gast; Bob Löwenberg

BACKGROUND High-dose chemoradiotherapy combined with autologous bone marrow transplantation can cure patients with disseminated, aggressive non-Hodgkins lymphoma in whom first-line chemotherapy has failed. In contrast, cure is rare with second-line chemotherapy. It has been suggested that patients with slow responses to the initial phase of first-line chemotherapy are at high risk for relapse. Therefore, such patients are potential candidates for early bone marrow transplantation. METHODS To investigate whether patients with slow responses, defined as only a partial response after three courses of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), would benefit from early transplantation, we conducted a prospective, randomized trial. The early application of high-dose chemoradiotherapy and autologous bone marrow transplantation was compared with the continuation of CHOP therapy for another five courses. Patients with complete responses after three courses of CHOP (fast responses) and patients who responded partially but still had tumor-positive marrow continued with another five courses of CHOP. The study end points were the response rate, overall survival, disease-free survival, and event-free survival. RESULTS Of 286 patients who could be evaluated for the rapidity of their response after three courses of CHOP, 38 percent had fast responses, 47 percent had slow responses, and 15 percent had no response. Among 106 patients with slow responses who had lymphoma-negative marrow, 69 patients (65 percent) were randomized. Seventy-four percent of the CHOP group and 68 percent of the transplantation group had complete remissions (P = 0.54). At four years the rates of overall, disease-free, and event-free survival were 85, 72, and 53 percent, respectively, in the CHOP group and 56, 60, and 41 percent in the transplantation group (P > 0.10). The disease-free survival in both groups did not differ significantly from that of nonrandomized patients with fast responses (54 percent at four years). CONCLUSIONS The early application of high-dose, marrow-ablative chemoradiotherapy with autologous bone marrow transplantation does not improve the outcome in patients with aggressive non-Hodgkins lymphoma that responds slowly to first-line CHOP chemotherapy.


Haematologica | 2010

Allogeneic Bone Marrow Transplantation in Multiple Myeloma

Gösta Gahrton; Sante Tura; Per Ljungman; Coralie Belanger; Lena Brandt; Michele Cavo; Thierry Facon; Alberto Granena; Martin Gore; Alois Gratwohl; Bob Löwenberg; Jukka Nikoskelainen; Josy Reiffers; Diana Samson; Leo F. Verdonck; Liisa Volin

Abstract Background and Methods. In contrast to autologous bone marrow transplants for hematologic cancers, allogeneic transplants contain no tumor cells that might cause a relapse. We report the results of such allogeneic bone marrow transplantation using HLA-compatible sibling donors in 90 patients with multiple myeloma performed in 26 European centers between 1983 and 1989. Results. At the time of the most recent follow-up, 79 months after the start of the study, 47 patients were alive and 43 were dead. The rate of complete remission after bone marrow transplantation was 43 percent for all patients and 58 percent for the patients who had engraftment. The actuarial survival at 76 months was 40 percent. The median duration of relapse-free survival among patients who were in complete remission after bone marrow transplantation was 48 months. The stage of the disease at diagnosis and the number of treatment regimens tried before bone marrow transplantation were predictive of the likelihood of complete remi...


The New England Journal of Medicine | 2011

Cytarabine Dose for Acute Myeloid Leukemia

Bob Löwenberg; Thomas Pabst; Edo Vellenga; Wim L.J. van Putten; H Schouten; Carlos Graux; Augustin Ferrant; Pieter Sonneveld; Bart J. Biemond; Alois Gratwohl; Georgine E. de Greef; Leo F. Verdonck; Martijn R. Schaafsma; Michael Gregor; Matthias Theobald; Urs Schanz; Johan Maertens; Gert J. Ossenkoppele

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.).


Journal of Clinical Oncology | 2013

High Prognostic Impact of Flow Cytometric Minimal Residual Disease Detection in Acute Myeloid Leukemia: Data From the HOVON/SAKK AML 42A Study

Monique Terwijn; Wim L.J. van Putten; Angele Kelder; V H J van der Velden; Rik A. Brooimans; Thomas Pabst; Johan Maertens; Nancy Boeckx; Georgine E. de Greef; Frank Preijers; Peter C. Huijgens; Angelika M. Dräger; Urs Schanz; Mojca Jongen-Lavrecic; Bart J. Biemond; Jakob Passweg; Michel van Gelder; Pierre W. Wijermans; Carlos Graux; Mario Bargetzi; Marie-Cecile Legdeur; Jürgen Kuball; Okke de Weerdt; Yves Chalandon; Urs Hess; Leo F. Verdonck; Jan W. Gratama; Yvonne J.M. Oussoren; Willemijn J. Scholten; Jennita Slomp

PURPOSE Half the patients with acute myeloid leukemia (AML) who achieve complete remission (CR), ultimately relapse. Residual treatment-surviving leukemia is considered responsible for the outgrowth of AML. In many retrospective studies, detection of minimal residual disease (MRD) has been shown to enable identification of these poor-outcome patients by showing its independent prognostic impact. Most studies focus on molecular markers or analyze data in retrospect. This study establishes the value of immunophenotypically assessed MRD in the context of a multicenter clinical trial in adult AML with sample collection and analysis performed in a few specialized centers. PATIENTS AND METHODS In adults (younger than age 60 years) with AML enrolled onto the Dutch-Belgian Hemato-Oncology Cooperative Group/Swiss Group for Clinical Cancer Research Acute Myeloid Leukemia 42A study, MRD was evaluated in bone marrow samples in CR (164 after induction cycle 1, 183 after cycle 2, 124 after consolidation therapy). RESULTS After all courses of therapy, low MRD values distinguished patients with relatively favorable outcome from those with high relapse rate and adverse relapse-free and overall survival. In the whole patient group and in the subgroup with intermediate-risk cytogenetics, MRD was an independent prognostic factor. Multivariate analysis after cycle 2, when decisions about consolidation treatment have to be made, confirmed that high MRD values (> 0.1% of WBC) were associated with a higher risk of relapse after adjustment for consolidation treatment time-dependent covariate risk score and early or later CR. CONCLUSION In future treatment studies, risk stratification should be based not only on risk estimation assessed at diagnosis but also on MRD as a therapy-dependent prognostic factor.


Journal of Clinical Oncology | 2010

High EVI1 Expression Predicts Outcome in Younger Adult Patients With Acute Myeloid Leukemia and Is Associated With Distinct Cytogenetic Abnormalities

Stefan M Groschel; Sanne Lugthart; Richard F. Schlenk; Karina Eiwen; Chantal S. Goudswaard; Wim J.L. van Putten; Sabine Kayser; Leo F. Verdonck; Michael Lübbert; Gert-Jan Ossenkoppele; Ulrich Germing; Ingo G.H. Schmidt-Wolf; Brigitte Schlegelberger; Jürgen Krauter; Arnold Ganser; Hartmut Döhner; Bob Löwenberg; Konstanze Döhner; Ruud Delwel

PURPOSE The purpose of this study was to investigate frequency and prognostic significance of high EVI1 expression in acute myeloid leukemia (AML). PATIENTS AND METHODS A diagnostic assay detecting multiple EVI1 splice variants was developed to determine the relative EVI1 expression by single real-time quantitative polymerase chain reaction in 1,382 newly diagnosed adult patients with AML younger than 60 years. Patients were treated on four Dutch-Belgian HOVON (n = 458) and two German-Austrian AML Study Group protocols (n = 924). Results The EVI1 assay was tested in the HOVON cohort and validated in the AMLSG cohort. High EVI1 levels (EVI1(+)) were found with similar frequencies in both cohorts combined, with a 10.7% incidence (148 of 1,382). EVI1(+) independently predicted low complete remission (CR) rate (odds ratio, 0.54; P = .002), adverse relapse-free survival (RFS; hazard ratio [HR], 1.32; P = .05), and event-free survival (EFS; HR, 1.46; P < .001). This adverse prognostic impact was more pronounced in the intermediate cytogenetic risk group (EFS; HR, 1.64; P < .001; and RFS; HR, 1.55; P = .02), and was also apparent in cytogenetically normal AML (EFS; HR, 1.67; P = .008). Besides inv(3)/t(3;3), EVI1(+) was significantly associated with chromosome abnormalities monosomy 7 and t(11q23), conferring prognostic impact within these two cytogenetic subsets. EVI1(+) was virtually absent in favorable-risk AML and AML with NPM1 mutations. Patients with EVI1(+) AML (n = 28) who received allogeneic stem cell transplantation in first CR had significantly better 5-year RFS (33% +/- 10% v 0%). CONCLUSION EVI1 expression in AML is unequally distributed in cytogenetic subtypes. It predicts poor outcome, particularly among intermediate cytogenetic risk AML. Patients with EVI1(+) AML may benefit from allogeneic transplantation in first CR. Pretreatment EVI1 screening should be included in risk stratification.


Journal of Clinical Oncology | 2012

Impact of FLT3 Internal Tandem Duplication on the Outcome of Related and Unrelated Hematopoietic Transplantation for Adult Acute Myeloid Leukemia in First Remission: A Retrospective Analysis

Salut Brunet; Myriam Labopin; Jordi Esteve; Jan J. Cornelissen; Gérard Socié; Anna Paola Iori; Leo F. Verdonck; Liisa Volin; Alois Gratwohl; Jorge Sierra; Mohamad Mohty; Vanderson Rocha

PURPOSE Patients with acute myeloid leukemia (AML) and FLT3/internal tandem duplication (FLT3/ITD) have poor prognosis if treated with chemotherapy only. Whether this alteration also affects outcome after allogeneic hematopoietic stem-cell transplantation (HSCT) remains uncertain. PATIENTS AND METHODS We analyzed 206 patients who underwent HLA-identical sibling and matched unrelated HSCTs reported to the European Group for Blood and Marrow Transplantation with a diagnosis of AML with normal cytogenetics and data on FLT3/ITD (present: n = 120, 58%; absent: n = 86, 42%). Transplantations were performed in first complete remission (CR) after myeloablative conditioning. RESULTS Compared with FLT3/ITD-negative patients, FLT3/ITD-positive patients had higher median leukocyte count at diagnosis (59 v 21 × 10(9)/L; P < .001) and shorter interval from CR to transplantation (87 v 99 days; P = .04). Other characteristics were similar in the two groups. At 2 years, relapse incidence (RI; ± standard deviation) was higher (30% ± 5% v 16% ± 5%; P = .006) and leukemia-free survival (LFS) lower (58% ± 5% v 71% ± 6%; P = .04) in FLT3/ITD-positive compared with FLT3/ITD-negative patients. In multivariate analyses, FLT3/ITD led to increased RI (hazard ratio [HR], 3.4; 95% CI, 1.46 to 7.94; P = .005), as did older age, female sex, shorter interval between CR and transplantation, and higher number of chemotherapy courses before achieving CR. FLT3/ITD positivity was associated with decreased LFS (HR, 0.37; 95% CI, 0.19 to 0.73; P = .002), along with older age and higher number of chemotherapy courses before achieving CR. CONCLUSION FLT3/ITD adversely affected the outcome of HSCT in the same direction it does after chemotherapy; despite this, more than half of the patients harboring this mutation who received transplants were alive and leukemia free at 2 years. To further improve the results, use of FLT3 inhibitors before or after HSCT deserves investigation.

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Bob Löwenberg

Erasmus University Medical Center

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Jan J. Cornelissen

Erasmus University Rotterdam

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Gert J. Ossenkoppele

VU University Medical Center

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Pieter Sonneveld

Erasmus University Rotterdam

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Ellen Meijer

Erasmus University Rotterdam

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Edo Vellenga

University Medical Center Groningen

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