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Dive into the research topics where Geertjan van Tienhoven is active.

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Featured researches published by Geertjan van Tienhoven.


The New England Journal of Medicine | 2009

Duration of androgen suppression in the treatment of prostate cancer

Michel Bolla; Theodorus M. de Reijke; Geertjan van Tienhoven; Alphonsus van den Bergh; Jorg R. Oddens; Philip Poortmans; Eliahu Gez; Paul Kil; Atif Akdas; Guy Soete; Oleg Kariakine; Elsbietha M. van der Steen-Banasik; Elena Musat; M. Pierart; Murielle Mauer; Laurence Collette

BACKGROUND The combination of radiotherapy plus long-term medical suppression of androgens (> or = 2 years) improves overall survival in patients with locally advanced prostate cancer. We compared the use of radiotherapy plus short-term androgen suppression with the use of radiotherapy plus long-term androgen suppression in the treatment of locally advanced prostate cancer. METHODS We randomly assigned patients with locally advanced prostate cancer who had received external-beam radiotherapy plus 6 months of androgen suppression to two groups, one to receive no further treatment (short-term suppression) and the other to receive 2.5 years of further treatment with a luteinizing hormone-releasing hormone agonist (long-term suppression). An outcome of noninferiority of short-term androgen suppression as compared with long-term suppression required a hazard ratio of more than 1.35 for overall survival, with a one-sided alpha level of 0.05. An interim analysis showed futility, and the results are presented with an adjusted one-sided alpha level of 0.0429. RESULTS A total of 1113 men were registered, of whom 970 were randomly assigned, 483 to short-term suppression and 487 to long-term suppression. After a median follow-up of 6.4 years, 132 patients in the short-term group and 98 in the long-term group had died; the number of deaths due to prostate cancer was 47 in the short-term group and 29 in the long-term group. The 5-year overall mortality for short-term and long-term suppression was 19.0% and 15.2%, respectively; the observed hazard ratio was 1.42 (upper 95.71% confidence limit, 1.79; P=0.65 for noninferiority). Adverse events in both groups included fatigue, diminished sexual function, and hot flushes. CONCLUSIONS The combination of radiotherapy plus 6 months of androgen suppression provides inferior survival as compared with radiotherapy plus 3 years of androgen suppression in the treatment of locally advanced prostate cancer. (ClinicalTrials.gov number, NCT00003026.)


Lancet Oncology | 2010

External irradiation with or without long-term androgen suppression for prostate cancer with high metastatic risk: 10-year results of an EORTC randomised study

Michel Bolla; Geertjan van Tienhoven; Padraig Warde; Jean Bernard Dubois; René-Olivier Mirimanoff; Guy Storme; Jacques Bernier; Abraham Kuten; Cora N. Sternberg; Ignace Billiet; José Lopez Torecilla; Raphael Pfeffer; Carmel Lino Cutajar; Theodore Van der Kwast; Laurence Collette

BACKGROUND We did a randomised phase 3 trial assessing the benefit of addition of long-term androgen suppression with a luteinising-hormone-releasing hormone (LHRH) agonist to external irradiation in patients with prostate cancer with high metastatic risk. In this report, we present the 10-year results. METHODS For this open-label randomised trial, eligible patients were younger than 80 years and had newly diagnosed histologically proven T1-2 prostatic adenocarcinoma with WHO histological grade 3 or T3-4 prostatic adenocarcinoma of any histological grade, and a WHO performance status of 0-2. Patients were randomly assigned (1:1) to receive radiotherapy alone or radiotherapy plus immediate androgen suppression. Treatment allocation was open label and used a minimisation algorithm with institution, clinical stage of the disease, results of pelvic-lymph-node dissection, and irradiation fields extension as minimisation factors. Patients were irradiated externally, once a day, 5 days a week, for 7 weeks to a total dose of 50 Gy to the whole pelvis, with an additional 20 Gy to the prostate and seminal vesicles. The LHRH agonist, goserelin acetate (3·6 mg subcutaneously every 4 weeks), was started on the first day of irradiation and continued for 3 years; cyproterone acetate (50 mg orally three times a day) was given for 1 month starting a week before the first goserelin injection. The primary endpoint was clinical disease-free survival. Analysis was by intention to treat. The trial is registered at ClinicalTrials.gov, number NCT00849082. FINDINGS Between May 22, 1987, and Oct 31, 1995, 415 patients were randomly assigned to treatment groups and were included in the analysis (208 radiotherapy alone, 207 combined treatment). Median follow-up was 9·1 years (IQR 5·1-12·6). 10-year clinical disease-free survival was 22·7% (95% CI 16·3-29·7) in the radiotherapy-alone group and 47·7% (39·0-56·0) in the combined treatment group (hazard ratio [HR] 0·42, 95% CI 0·33-0·55, p<0·0001). 10-year overall survival was 39·8% (95% CI 31·9-47·5) in patients receiving radiotherapy alone and 58·1% (49·2-66·0) in those allocated combined treatment (HR 0·60, 95% CI 0·45-0·80, p=0·0004), and 10-year prostate-cancer mortality was 30·4% (95% CI 23·2-37·5) and 10·3% (5·1-15·4), respectively (HR 0·38, 95% CI 0·24-0·60, p<0·0001). No significant difference in cardiovascular mortality was noted between treatment groups both in patients who had cardiovascular problems at study entry (eight of 53 patients in the combined treatment group had a cardiovascular-related cause of death vs 11 of 63 in the radiotherapy group; p=0·60) and in those who did not (14 of 154 vs six of 145; p=0·25). Two fractures were reported in patients allocated combined treatment. INTERPRETATION In patients with prostate cancer with high metastatic risk, immediate androgen suppression with an LHRH agonist given during and for 3 years after external irradiation improves 10-year disease-free and overall survival without increasing late cardiovascular toxicity.


Radiotherapy and Oncology | 1999

THE EFFECT OF A SINGLE FRACTION COMPARED TO MULTIPLE FRACTIONS ON PAINFUL BONE METASTASES : A GLOBAL ANALYSIS OF THE DUTCH BONE METASTASIS STUDY

Elsbeth Steenland; Jan Willem Leer; Hans C. van Houwelingen; Wendy J. Post; Wilbert B. van den Hout; Job Kievit; Hanneke C.J.M. de Haes; Hendrik Martijn; Bing Oei; Ernest Vonk; Elzbieta M. van der Steen-Banasik; Ruud Wiggenraad; Jaap Hoogenhout; Carla C. Wárlám-Rodenhuis; Geertjan van Tienhoven; Rinus Wanders; Jacqueline Pomp; M. van Reijn; Thijs van Mierlo; Ewald Rutten

PURPOSE To answer the question whether a single fraction of radiotherapy that is considered more convenient to the patient is as effective as a dose of multiple fractions for palliation of painful bone metastases. PATIENTS 1171 patients were randomised to receive either 8 Gy x 1 (n = 585) or 4 Gy x 6 (n = 586). The primary tumour was in the breast in 39% of the patients, in the prostate in 23%, in the lung in 25% and in other locations in 13%. Bone metastases were located in the spine (30%), pelvis (36%), femur (10%), ribs (8%), humerus (6%) and other sites (10%). METHOD Questionnaires were mailed to collect information on pain, analgesics consumption, quality of life and side effects during treatment. The main endpoint was pain measured on a pain scale from 0 (no pain at all) to 10 (worst imaginable pain). Costs per treatment schedule were estimated. RESULTS On average, patients participated in the study for 4 months. Median survival was 7 months. Response was defined as a decrease of at least two points as compared to the initial pain score. The difference in response between the two treatment groups proved not significant and stayed well within the margin of 10%. Overall, 71% experienced a response at some time during the first year. An analysis of repeated measures confirmed that the two treatment schedules were equivalent in terms of palliation. With regard to pain medication, quality of life and side effects no differences between the two treatment groups were found. The total number of retreatments was 188 (16%). This number was 147 (25%) in the 8 Gy x 1 irradiation group and 41 (7%) in the 4 Gy x 6 group. It was shown that the level of pain was an important reason to retreat. There were also indications that doctors were more willing to retreat patients in the single fraction group because time to retreatment was substantially shorter in this group and the preceding pain score was lower. Unexpectedly, more pathological fractures were observed in the single fraction group, but the absolute percentage was low. In a cost-analysis, the costs of the 4 Gy x 6 and the 8 Gy x 1 treatment schedules were calculated at 2305 and 1734 Euro respectively. Including the costs of retreatment reduced this 25% cost difference to only 8%. The saving of radiotherapy capacity, however, was considered the major economic advantage of the single dose schedule. CONCLUSION The global analysis of the Dutch study indicates the equality of a single fraction as compared to a 6 fraction treatment in patients with painful bone metastases provided that 4 times more retreatments are accepted in the single dose group. This equality is also shown in long term survivors. A more detailed analysis of the study is in progress.


Journal of Clinical Oncology | 2005

The Effect of Low Molecular Weight Heparin on Survival in Patients With Advanced Malignancy

Clara P. W. Klerk; Susanne M. Smorenburg; Hans Martin Otten; A.W.A. Lensing; Martin H. Prins; Franco Piovella; Paolo Prandoni; Monique M.E.M. Bos; Dick J. Richel; Geertjan van Tienhoven; Harry R. Buller

PURPOSE Studies in cancer patients with venous thromboembolism suggested that low molecular weight heparin may prolong survival. In a double-blind study, we evaluated the effect of low molecular weight heparin on survival in patients with advanced malignancy without venous thromboembolism. METHODS Patients with metastasized or locally advanced solid tumors were randomly assigned to receive a 6-week course of subcutaneous nadroparin or placebo. The primary efficacy analysis was based on time from random assignment to death. The primary safety outcome was major bleeding. RESULTS In total, 148 patients were allocated to nadroparin and 154 patients were allocated to placebo. Mean follow-up was 1 year. In the intention-to-treat analysis the overall hazard ratio of mortality was 0.75 (95% CI, 0.59 to 0.96) with a median survival of 8.0 months in the nadroparin recipients versus 6.6 months in the placebo group. After adjustment for potential confounders, the treatment effect remained statistically significant. Major bleeding occurred in five (3%) of nadroparin-treated patients and in one (1%) of the placebo recipients (P = .12). In the a priori specified subgroup of patients with a life expectancy of 6 months or more at enrollment, the hazard ratio was 0.64 (95% CI, 0.45 to 0.90) with a median survival of 15.4 and 9.4 months, respectively. For patients with a shorter life expectancy, the hazard ratio was 0.88 (95% CI, 0.62 to 1.25). CONCLUSION A brief course of subcutaneous low molecular weight heparin favorably influences the survival in patients with advanced malignancy and deserves additional clinical evaluation.


Journal of Clinical Oncology | 2001

Differences in Risk Factors for Local and Distant Recurrence After Breast-Conserving Therapy or Mastectomy for Stage I and II Breast Cancer: Pooled Results of Two Large European Randomized Trials

Adri C. Voogd; Maja Nielsen; Johannes L. Peterse; Mogens Blichert-Toft; Harry Bartelink; Marie Overgaard; Geertjan van Tienhoven; Knud West Andersen; Richard Sylvester; Joop A. van Dongen

PURPOSE Risk factors for local and distant recurrence after breast-conserving therapy and mastectomy were compared to define guidelines for the decision making between both treatments. PATIENTS AND METHODS The data of two randomized clinical trials for stage I and II breast cancer patients were pooled. The total number of patients in the study was 1,772, of whom 879 underwent breast conservation, and 893, modified radical mastectomy. Representative slides of the primary tumor were available for histopathologic review in 1,610 cases (91%). RESULTS There were 79 patients with local recurrence after breast-conservation and 80 after mastectomy, the 10-year rates being 10% (95% confidence interval [CI], 8% to 13%) and 9% (95% CI, 7% to 12%), respectively. Age no more than 35 years (compared with age >60: hazard ratio [HR], 9.24; 95% CI, 3.74 to 22.81) and an extensive intraductal component (HR, 2.52; 95% CI, 1.26 to 5.00) were significantly associated with an increased risk of local recurrence after breast-conserving therapy. Vascular invasion was predictive of the risk of local recurrence, irrespective of the type of primary treatment (P <.01). Tumor size, nodal status, high histologic grade, and vascular invasion were all highly significant predictors of distant disease after breast-conserving therapy and mastectomy (P <.01). Age no more than 35 years and microscopic involvement of the excision margin were additional independent predictors of distant disease after breast-conserving therapy (P <.01). CONCLUSION Age no more than 35 years and the presence of an extensive intraductal component are associated with an increased risk of local recurrence after breast-conserving therapy. Vascular invasion causes a higher risk of local recurrence after mastectomy as well as after breast-conserving therapy and should therefore not be used for deciding between the two treatments.


Lancet Oncology | 2014

Radiotherapy or surgery of the axilla after a positive sentinel node in breast cancer (EORTC 10981-22023 AMAROS): a randomised, multicentre, open-label, phase 3 non-inferiority trial

M. Donker; Geertjan van Tienhoven; Marieke E. Straver; Philip Meijnen; Cornelis J. H. van de Velde; Robert E. Mansel; Luigi Cataliotti; A. Helen Westenberg; Jean H. G. Klinkenbijl; Lorenzo Orzalesi; Willem H. Bouma; Huub van der Mijle; G.A.P. Nieuwenhuijzen; Sanne C. Veltkamp; Leen Slaets; Nicole Duez; Peter W de Graaf; Thijs van Dalen; A. Marinelli; Herman Rijna; Marko Snoj; N.J. Bundred; Jos W.S. Merkus; Yazid Belkacemi; Patrick Petignat; Dominic A.X. Schinagl; Corneel Coens; Carlo Messina; Jan Bogaerts; Emiel J. Th. Rutgers

BACKGROUND If treatment of the axilla is indicated in patients with breast cancer who have a positive sentinel node, axillary lymph node dissection is the present standard. Although axillary lymph node dissection provides excellent regional control, it is associated with harmful side-effects. We aimed to assess whether axillary radiotherapy provides comparable regional control with fewer side-effects. METHODS Patients with T1-2 primary breast cancer and no palpable lymphadenopathy were enrolled in the randomised, multicentre, open-label, phase 3 non-inferiority EORTC 10981-22023 AMAROS trial. Patients were randomly assigned (1:1) by a computer-generated allocation schedule to receive either axillary lymph node dissection or axillary radiotherapy in case of a positive sentinel node, stratified by institution. The primary endpoint was non-inferiority of 5-year axillary recurrence, considered to be not more than 4% for the axillary radiotherapy group compared with an expected 2% in the axillary lymph node dissection group. Analyses were by intention to treat and per protocol. The AMAROS trial is registered with ClinicalTrials.gov, number NCT00014612. FINDINGS Between Feb 19, 2001, and April 29, 2010, 4823 patients were enrolled at 34 centres from nine European countries, of whom 4806 were eligible for randomisation. 2402 patients were randomly assigned to receive axillary lymph node dissection and 2404 to receive axillary radiotherapy. Of the 1425 patients with a positive sentinel node, 744 had been randomly assigned to axillary lymph node dissection and 681 to axillary radiotherapy; these patients constituted the intention-to-treat population. Median follow-up was 6·1 years (IQR 4·1-8·0) for the patients with positive sentinel lymph nodes. In the axillary lymph node dissection group, 220 (33%) of 672 patients who underwent axillary lymph node dissection had additional positive nodes. Axillary recurrence occurred in four of 744 patients in the axillary lymph node dissection group and seven of 681 in the axillary radiotherapy group. 5-year axillary recurrence was 0·43% (95% CI 0·00-0·92) after axillary lymph node dissection versus 1·19% (0·31-2·08) after axillary radiotherapy. The planned non-inferiority test was underpowered because of the low number of events. The one-sided 95% CI for the underpowered non-inferiority test on the hazard ratio was 0·00-5·27, with a non-inferiority margin of 2. Lymphoedema in the ipsilateral arm was noted significantly more often after axillary lymph node dissection than after axillary radiotherapy at 1 year, 3 years, and 5 years. INTERPRETATION Axillary lymph node dissection and axillary radiotherapy after a positive sentinel node provide excellent and comparable axillary control for patients with T1-2 primary breast cancer and no palpable lymphadenopathy. Axillary radiotherapy results in significantly less morbidity. FUNDING EORTC Charitable Trust.


Cancer | 1999

Local recurrence after breast conservation therapy for early stage breast carcinoma - Detection, treatment, and outcome in 266 patients

Adri C. Voogd; Geertjan van Tienhoven; Hans L. Peterse; Mariad A. Crommelin; Emiel J. Th. Rutgers; Cornelis J. H. van de Velde; Bert N. van Geel; Annerie Slot; Patrick T. Rodrigus; Jan J. Jobsen; Maarten F. von Meyenfeldt; Jan Willem Coebergh

Controversy exists concerning the roles of mammography and physical examination in the detection of local recurrence after conservation therapy for breast carcinoma. In addition, the prognostic factors for and optimal treatment of patients with local recurrence are uncertain.


Journal of Clinical Oncology | 2010

Adjuvant Gemcitabine Alone Versus Gemcitabine-Based Chemoradiotherapy After Curative Resection for Pancreatic Cancer: A Randomized EORTC-40013-22012/FFCD-9203/GERCOR Phase II Study

Jean-Luc Van Laethem; Pascal Hammel; F. Mornex; D. Azria; Geertjan van Tienhoven; Philippe Vergauwe; Marc Peeters; Marc Polus; Michel Praet; Murielle Mauer; Laurence Collette; Volker Budach; Manfred B. Lutz; Eric Van Cutsem; Karin Haustermans

PURPOSE The role of adjuvant chemoradiotherapy (CRT) in resectable pancreatic cancer is still debated. This randomized phase II intergroup study explores the feasibility and tolerability of a gemcitabine-based CRT regimen after R0 resection of pancreatic head cancer. PATIENTS AND METHODS Within 8 weeks after surgery, patients were randomly assigned to receive either four cycles of gemcitabine (control arm) or gemcitabine for two cycles followed by weekly gemcitabine with concurrent radiation (50.4 Gy; CRT arm). The primary objective was to exclude a < 60% treatment completion and a > 40% rate of grade 4 hematologic or GI toxicity in the CRT arm with type I and II errors of 10%. Secondary end points were late toxicity, disease-free survival (DFS), and overall survival (OS). RESULTS Between September 2004 and January 2007, 90 patients were randomly assigned (45:45). Patient characteristics were similar in both arms. Treatment was completed per protocol by 86.7% and 73.3% (80% CI, 63.1% to 81.9%; 95% CI, 58.1% to 85.4%) in the control and CRT arms, respectively, and grade 4 toxicity was 0% and 4.7% (two of 43; 80% CI, 1.2% to 11.9%), respectively. In the CRT arm, three patients experienced grade 3-related late toxicity. Median DFS was 12 months in the CRT arm and 11 months in the control arm. Median OS was 24 months in both arms. First local recurrence was less frequent in the CRT arm (11% v 24%). CONCLUSION Adjuvant gemcitabine-based CRT is feasible, well-tolerated, and not deleterious; adding this treatment to full-dose adjuvant gemcitabine after resection of pancreatic cancer should be evaluated in a phase III trial.


Journal of Clinical Oncology | 2010

Role of Axillary Clearance After a Tumor-Positive Sentinel Node in the Administration of Adjuvant Therapy in Early Breast Cancer

Marieke E. Straver; Philip Meijnen; Geertjan van Tienhoven; Cornelis J. H. van de Velde; Robert E. Mansel; Jan Bogaerts; Gaston Demonty; Nicole Duez; Luigi Cataliotti; Jean H. G. Klinkenbijl; Helen A. Westenberg; Hueb van der Mijle; Coen W. Hurkmans; Emeil J. T. Rutgers

PURPOSE The After Mapping of the Axilla: Radiotherapy or Surgery? (AMAROS) phase III study compares axillary lymph node dissection (ALND) and axillary radiation therapy (ART) in early breast cancer patients with tumor-positive sentinel nodes. In the ART arm, the extent of nodal involvement remains unknown, which could have implications on the administration of adjuvant therapy. In this preliminary analysis, we studied the influence of random assignment to ALND or ART on the choice for adjuvant treatment. PATIENTS AND METHODS In the first 2,000 patients enrolled in the AMAROS trial, we analyzed the administration of adjuvant systemic therapy. Multivariate analysis was used to assess variables affecting the administration of adjuvant chemotherapy. Adjuvant therapy was applied according to institutional guidelines. Results Of 2,000 patients, 566 patients had a positive sentinel node and were treated per random assignment. There was no significant difference in the administration of adjuvant systemic therapy. In the ALND and ART arms, 58% (175 of 300) and 61% (162 of 266) of the patients, respectively, received chemotherapy. Endocrine therapy was administered in 78% (235 of 300) of the patients in the ALND arm and in 76% (203 of 266) of the patients in the ART arm. Treatment arm was not a significant factor in the decision, and no interactions between treatment arm and other factors were observed. Multivariate analysis showed that age, tumor grade, multifocality, and size of the sentinel node metastasis significantly affected the administration of chemotherapy. Within the ALND arm, the extent of nodal involvement remained not significant in a sensitivity multivariate analysis. CONCLUSION Absence of knowledge regarding the extent of nodal involvement in the ART arm appears to have no major impact on the administration of adjuvant therapy.


Cancer | 2000

Feasibility and efficacy of high dose conformal radiotherapy for patients with locally advanced pancreatic carcinoma.

Heleen M. Ceha; Geertjan van Tienhoven; Dirk J. Gouma; Cees H. N. Veenhof; Christoph J. Schneider; Erik A. J. Rauws; Saffire S. K. S. Phoa; Dionisio Gonzalez Gonzalez

The feasibility and efficacy of high dose conformal radiotherapy were examined in the treatment of patients with locally advanced, unresectable pancreatic carcinoma.

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A. Bel

University of Amsterdam

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Eelco Lens

University of Amsterdam

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Laurence Collette

European Organisation for Research and Treatment of Cancer

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Philip Poortmans

Radboud University Nijmegen

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Coen W. Hurkmans

Netherlands Cancer Institute

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