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Dive into the research topics where A. W. Dekker is active.

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Featured researches published by A. W. Dekker.


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

BACKGROUNDnHigh-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.nnnMETHODSnTo 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.nnnRESULTSnOf 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).nnnCONCLUSIONSnThe 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.


Leukemia | 2004

Significant difference in outcome for adolescents with acute lymphoblastic leukemia treated on pediatric vs adult protocols in the Netherlands

J M de Bont; B. van der Holt; A. W. Dekker; A. van der Does-van den Berg; Pieter Sonneveld; R. Pieters

Significant difference in outcome for adolescents with acute lymphoblastic leukemia treated on pediatric vs adult protocols in the Netherlands


Journal of Clinical Oncology | 1998

Mitoxantrone versus daunorubicin in induction-consolidation chemotherapy--the value of low-dose cytarabine for maintenance of remission, and an assessment of prognostic factors in acute myeloid leukemia in the elderly: final report. European Organization for the Research and Treatment of Cancer and the Dutch-Belgian Hemato-Oncology Cooperative Hovon Group.

B Lowenberg; Stefan Suciu; E. Archimbaud; Hans L. Haak; Pierre Stryckmans; R. De Cataldo; A. W. Dekker; Zwi N. Berneman; A. Thyss; J van der Lelie; Pieter Sonneveld; G. Visani; Georges Fillet; M. Hayat; Anne Hagemeijer; G. Solbu; Robert Zittoun

PURPOSE AND METHODSnOptimization of remission-induction and postremission therapy in elderly individuals with acute myeloid leukemia (AML) was the subject of a randomized study in patients older than 60 years. Remission-induction chemotherapy was compared between daunomycin (DNR) 30 mg/m2 on days 1, 2, and 3 versus mitoxantrone (MTZ) 8 mg/m2 on days 1, 2, and 3, both plus cytarabine (Ara-C) 100 mg/m2 on days 1 to 7. Following complete remission (CR), patients received one additional cycle of DNR or MTZ chemotherapy and were then eligible for a second randomization between eight cycles of low-dose (LD)-Ara-C 10 mg/m2 subcutaneously every 12 hours for 1 2 days every 6 weeks or no further treatment.nnnRESULTSnA total of 242 patients was randomized to DNR and 247 to MTZ. Median age of both study groups was 68 years. Secondary AML was documented in 26% and 25% of patients in either arm. The probability of attaining CR was greater (P = .069) with MTZ (47%) than with DNR (38%). Median duration of neutropenia was 19 (DNR) and 22 days (MTZ). The greater response rate to MTZ therapy correlated with reduced occurrence of chemotherapy resistance (32% v 47%, P = .001). With a median follow-up of 6 years, 5-year disease-free survival (DFS) is 8% in each arm. Overall survival estimates are not different between the groups (6% v 9% at 5 yrs). Poor performance status at diagnosis, high WBC count, older age, secondary AML, and presence of cytogenetic abnormalities all had an adverse impact on survival. Secondary AML and abnormal cytogenetics predicted for shorter duration of CR. Among complete responders, 74 assessable patients were assigned to Ara-C and 73 to no further therapy. Actuarial DFS was significantly longer (P = .006) for Ara-C-treated (13% [SE = 4.0%] at 5 years) versus nontreated patients (7% [SE = 3%]), but overall survival was similar (P = .29): 18% (SE = 4.6%) versus 15% (SE = 4.3%). Meta-analysis on the value of Ara-C postremission therapy confirms these results.nnnCONCLUSIONnIn previously untreated elderly patients with AML, MTZ induction therapy produces a slightly better CR rate than does a DNR-containing regimen, but it has no significant effect on remission duration and survival. Ara-C in maintenance may prolong DFS, but it did not improve survival.


Annals of Internal Medicine | 1987

Infection Prophylaxis in Acute Leukemia: A Comparison of Ciprofloxacin with Trimethoprim-Sulfamethoxazole and Colistin

A. W. Dekker; Maja Rozenberg-Arska; Jan Verhoef

Fifty-six patients receiving remission induction treatment for acute leukemia were studied in a randomized trial comparing ciprofloxacin with trimethoprim-sulfamethoxazole plus colistin for prevention of infections. Both groups received amphotericin B for antifungal prophylaxis. Six major infections occurred in 28 patients receiving ciprofloxacin, and 11 major infections occurred in 28 patients receiving trimethoprim-sulfamethoxazole plus colistin. No infections caused by gram-negative bacilli were seen in the ciprofloxacin group (p less than 0.02). Ciprofloxacin prevented colonization with resistant gram-negative bacilli, but 12 resistant colonizing strains were isolated from 10 patients receiving trimethoprim-sulfamethoxazole plus colistin (p less than 0.01). Ciprofloxacin was better tolerated: 23 of 28 patients were highly compliant to the drug, compared with 15 of 28 patients in the trimethoprim-sulfamethoxazole group (p less than 0.05). These results suggest that ciprofloxacin is a promising drug for the prevention of infection in patients with granulocytopenia.


Annals of Internal Medicine | 1981

Prevention of infection by trimethoprim-sulfamethoxazole plus amphotericin B in patients with acute nonlymphocytic leukaemia.

A. W. Dekker; Maja Rozenberg-Arska; Jan J. Sixma; Jan Verhoef

Fifty-two patients with nonlymphocytic leukaemia were studied during remission induction treatment in a randomized trial to ascertain the effect of prophylactic oral trimethoprim-sulfamethoxazole on infection and fever rate. A decrease in the total number of acquired infections was found (16 infections in the group given trimethoprim-sulfamethoxazole versus 31 in the control group, p less than 0.01). The number of patients without any infection in the trimethoprim-sulfamethoxazole group was 13 compared to only three in the control group (p less than 0.01). Patients in the trimethoprim-sulfamethoxazole group needed parenteral antibiotics during 33% of the days they were granulocytopenic compared to 61% of these days for patients in the control group. However, six of nine bacteriologically documented infections in the trimethoprim-sulfamethoxazole group were caused by resistant microorganisms compared to two out of 20 in the control group.


Journal of Clinical Oncology | 1990

Autologous bone marrow transplantation in acute myeloid leukemia in first remission: results of a Dutch prospective study.

Bob Löwenberg; L J Verdonck; A. W. Dekker; R. Willemze; Ferdinand E. Zwaan; M de Planque; J. Abels; Pieter Sonneveld; J van der Lelie; R. Goudsmit

Recent investigations have suggested a role for marrow ablative chemotherapy and radiotherapy given with autologous bone marrow transplantation (auto-BMT) in the treatment of acute myeloid leukemia (AML), but prospective studies have not been reported. We assessed the comparative values of auto-BMT and allogeneic marrow transplantation (allo-BMT) in 117 15- to 60-year-old consecutive patients (median, 43 years) with AML following remission-induction therapy. In 32 cases of the 90 (77%) complete responders, auto-BMT (nonpurged) was undertaken at a median of 3.8 months and in 23 eligible cases human leukocyte antigen (HLA)-matched allo-BMT occurred at 3.0 months after attainment of remission. Thus, nearly 60% of complete responders had access to transplantation, the others being withdrawn because of relapse, refusal, or other causes. Median time of regeneration to neutrophils 0.5 x 10(9)/L and platelets 20 x 10(9)/L were 39 and 63 days following auto-BMT versus 21 and 19 days after allo-BMT, respectively. AML relapse was the predominant cause of failure after auto-BMT (17 of 32) and procedure-related death was seen in three of 32 patients. The actuarial rates of relapse at 3 years are 60% (auto-BMT) and 34% (allo-BMT) (log-rank, P = .03). Patients treated with auto-BMT and allo-BMT have an overall survival of 37% and 66% at 3 years posttransplant, respectively (P = .05). Relapse-free 3-year survival rates are 35% and 51%, respectively (P = .12). Survival of the nongrafted complete responders is less than 10%. This study shows that allo-BMT in adult patients with AML in first complete remission (CR) results in more rapid hematopoietic reconstitution, is followed by fewer recurrences, and provides better survival than auto-BMT.


British Journal of Haematology | 2002

Early and late invasive pneumococcal infection following stem cell transplantation: a European Bone Marrow Transplantation survey

Dan Engelhard; Catherine Cordonnier; Peter J. Shaw; Terttu Parkalli; Christine Guenther; R Martino; A. W. Dekker; H. Grant Prentice; Anita Gustavsson; W. Nürnberger; Per Ljungman

Summary.u2002 Streptococcus pneumoniae (S. pneumoniae) may cause severe and lethal infections months and years following stem cell transplantation (SCT). In a prospective survey over a 3·5‐year period, we assessed the incidence, risk factors and outcome for invasive pneumococcal infection (IPI) following SCT. Fifty‐one episodes of IPI were reported: 43 episodes after bone marrow transplantation (BMT) and 8 after peripheral blood stem cell transplantation (PBSCT); 35 after allogeneic SCT and 16 after autologous SCT. Seven IPI episodes, all bacteraemias, were defined as early, occurring 1–35u2003d (median 3u2003d) post transplantation. Forty‐four episodes were defined as late (≥u2003100u2003d post SCT), occurring 4u2003months to 10u2003years (median 17u2003months) post transplantation. The incidences of early and late IPI were 2·03/1000 and 8·63/1000 transplantations respectively (Pu2003=u20030·001). A higher incidence of late IPI was observed after BMT than after PBSCT (10·99 versus 3·23/1000; Pu2003<u20030·01) and after allogeneic versus autologous SCT (12·20 versus 4·60/1000; Pu2003<u20030·01). There was a higher estimated incidence of IPI in allogeneic patients with than in those without graft‐versus‐host disease (GVHD) (18·85 versus 8·25/1000; Pu2003=u20030·015). The mortality rate was 20%, including 2/7 of early and 8/44 of late IPI. S. pneumoniae is a rare but important complication during the aplastic phase after SCT. In conclusion, S. pneumoniae is a significant cause of morbidity late post‐transplantation, especially in allogeneic patients, and particularly those with GVHD. The high IPI mortality rate, both early and late post‐transplantation, requires preventive approaches, mainly effective immunization.


Blood | 2009

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.

Jan J. Cornelissen; Bronno van der Holt; Gregor Verhoef; Mars B. van 't Veer; Marinus H. J. van Oers; Harry C. Schouten; Gert J. Ossenkoppele; Pieter Sonneveld; Johan Maertens; Marinus van Marwijk Kooy; Martijn R. Schaafsma; Pierre W. Wijermans; Douwe H. Biesma; S. Wittebol; Paul J. Voogt; Joke W. Baars; Pierre Zachee; Leo F. Verdonck; Bob Löwenberg; A. W. Dekker

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.


British Journal of Haematology | 1999

Vincristine, doxorubicin and dexamethasone (VAD) administered as rapid intravenous infusion for first-line treatment in untreated multiple myeloma

Christine M. Segeren; Pieter Sonneveld; B. van der Holt; Joke W. Baars; Douwe H. Biesma; J. J. Cornellissen; Alexandra J. Croockewit; A. W. Dekker; W. E. Fibbe; B Lowenberg; M. van Marwijk Kooy; M. H. J. Van Oers; D. J. Richel; H Schouten; Edo Vellenga; G. Verhoef; P. Wijermans; S. Wittebol; Hm Lokhorst

We examined the feasibility of achieving a rapid response in patients with previously untreated multiple myeloma by administering vincristine 0.4u2003mg and doxorubicin 9u2003mg/m2 as a rapid intravenous infusion for 4u2003d together with intermittent high‐dose dexamethasone 40u2003mg (VAD) for remission induction treatment in patients who were scheduled to receive high‐dose therapy. 139 patients (86 male, 53 female; median age 53 years, range 32–65 years; Durie & Salmon stage IIA: 42, IIB: one, IIIA: 89, IIIB: seven) were included in a prospective multicentre study in which VAD was administered as remission induction treatment and was followed by intensified treatment. The response was evaluated according to the criteria of the Eastern Cooperative Oncology Group (ECOG). The results of treatment were evaluable in 134 patients. Five patients died before evaluation. 86 patients (62%) achieved a partial response (PR) and seven patients (5%) achieved a complete response (CR), which equates to a response rate of 67%. The main side‐effect was mild neurotoxicity, which was observed in 18% of the patients. Fever or infections were reported in 27% of the patients. VAD administered as an outpatient regimen, based on rapid intravenous infusion, is an effective induction regimen for untreated myeloma with a 67% response rate and acceptable toxicity.


Clinical Infectious Diseases | 2005

Frequent Detection of Respiratory Viruses in Adult Recipients of Stem Cell Transplants with the Use of Real-Time Polymerase Chain Reaction, Compared with Viral Culture

Marian G. J. van Kraaij; Leontine J. R. van Elden; Anton M. van Loon; Karin A. W. Hendriksen; Laurens Laterveer; A. W. Dekker; Monique Nijhuis

Abstract Background. Respiratory virus infections have been recognized as important causes of severe pneumonia in patients who have undergone stem cell transplantation (SCT). Reported incidences of respiratory virus infection in adult SCT recipients vary in the literature from 3.5% to 36% when determined by viral culture. However, a more sensitive method to assess the presence of respiratory viruses in the lower airways may be important for delineation of the true incidence of respiratory virus—associated pneumonia and may be essential for guidance on implementation of antiviral therapy and prevention or limitation of nosocomial spread of infection with respiratory viruses. Methods. To determine the incidence and severity of respiratory tract illness (RTI) and to assess the diagnostic value of real-time reverse-transcriptase polymerase chain reaction (RT-PCR) versus viral culture, 72 SCT recipients were monitored during a 6-month period. Results. A respiratory virus was detected in 21% of episodes of RTI by viral culture and in 63% of RTI episodes by real-time RT-PCR (P < .0001). In lower respiratory tract illness, real-time RT-PCR was much more sensitive than viral culture for detection of respiratory virus (73% vs. 9%; P = .008). The mortality rate for patients with respiratory virus—associated lower respiratory tract illness (25%) was similar to rates reported elsewhere. Respiratory viruses (predominantly rhinovirus) were detected by real-time RT-PCR in 9% of samples obtained from symptom-free SCT recipients at predetermined times by real-time RT-PCR and by viral culture in 1% (P < .0001), indicating that asymptomatic shedding of respiratory viruses also occurs. Conclusion. We conclude that, although asymptomatic shedding of respiratory virus occurs, respiratory viruses are frequent causes of RTI in SCT recipients.

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Pieter Sonneveld

Erasmus University Rotterdam

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Lf Verdonck

University of Groningen

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Bob Löwenberg

Erasmus University Medical Center

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Edo Vellenga

University Medical Center Groningen

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Jan J. Cornelissen

Erasmus University Rotterdam

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