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Dive into the research topics where Walter Van den Bogaert is active.

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Featured researches published by Walter Van den Bogaert.


The New England Journal of Medicine | 1992

Effects of Concomitant Cisplatin and Radiotherapy on Inoperable Non-Small-Cell Lung Cancer

C. Schaake-Koning; Walter Van den Bogaert; Otilia Dalesio; Jan Festen; Jaap Hoogenhout; Paul Van Houtte; A. Kirkpatrick; Mia Koolen; B. Maat; Arie Nijs; Alain Renaud; Patrick Rodrigus; Lon Schuster-Uitterhoeve; Jean-Paul Sculier; Nico van Zandwijk; Harry Bartelink

BACKGROUND AND METHODS Cisplatin (cis-diamminedichloroplatinum) has been reported to enhance the cell-killing effect of radiation, an effect whose intensity varies with the schedule of administration. We randomly assigned 331 patients with nonmetastatic inoperable non-small-cell lung cancer to one of three treatments: radiotherapy for two weeks (3 Gy given 10 times, in five fractions a week), followed by a three-week rest period and then radiotherapy for two more weeks (2.5 Gy given 10 times, five fractions a week); radiotherapy on the same schedule, combined with 30 mg of cisplatin per square meter of body-surface area, given on the first day of each treatment week; or radiotherapy on the same schedule, combined with 6 mg of cisplatin per square meter, given daily before radiotherapy. RESULTS Survival was significantly improved in the radiotherapy-daily-cisplatin group as compared with the radiotherapy group (P = 0.009): survival in the radiotherapy-daily-cisplatin group was 54 percent at one year, 26 percent at two years, and 16 percent at three years, as compared with 46 percent, 13 percent, and 2 percent, respectively, in the radiotherapy group. Survival in the radiotherapy-weekly-cisplatin group was intermediate (44 percent, 19 percent, and 13 percent) and not significantly different from survival in either of the other two groups. The survival benefit of daily combined treatment was due to improved control of local disease (P = 0.003). Survival without local recurrence was 59 percent at one year and 31 percent at two years in the radiotherapy-daily-cisplatin group; 42 percent and 30 percent, respectively, in the radiotherapy-weekly-cisplatin group; and 41 percent and 19 percent, respectively, in the radiotherapy group. Cisplatin induced nausea and vomiting in 86 percent of the patients given it weekly and in 78 percent of those given it daily; these effects were severe in 26 percent and 28 percent, respectively. CONCLUSIONS Cisplatin, given daily in combination with the radiotherapy described here to patients with nonmetastatic but inoperable non-small-cell lung cancer, improved rates of survival and control of local disease at the price of substantial side effects.


Journal of Clinical Oncology | 2007

Impact of a Higher Radiation Dose on Local Control and Survival in Breast-Conserving Therapy of Early Breast Cancer: 10-Year Results of the Randomized Boost Versus No Boost EORTC 22881-10882 Trial

Harry Bartelink; Jean-Claude Horiot; Philip Poortmans; H. Struikmans; Walter Van den Bogaert; A. Fourquet; Jos J. Jager; W.J. Hoogenraad; S. Bing Oei; Carla C. Wárlám-Rodenhuis; M. Pierart; Laurence Collette

Purpose To investigate the long-term impact of a boost radiation dose of 16 Gy on local control, fibrosis, and overall survival for patients with stage I and II breast cancer who underwent breast-conserving therapy. Patients and Methods A total of 5,318 patients with microscopically complete excision followed by whole-breast irradiation of 50 Gy were randomly assigned to receive either a boost dose of 16 Gy (2,661 patients) or no boost dose (2,657 patients), with a median follow-up of 10.8 years. Results The median age was 55 years. Local recurrence was reported as the first treatment failure in 278 patients with no boost versus 165 patients with boost; at 10 years, the cumulative incidence of local recurrence was 10.2% versus 6.2% for the no boost and the boost group, respectively (P < .0001). The hazard ratio of local recurrence was 0.59 (0.46 to 0.76) in favor of the boost, with no statistically significant interaction per age group. The absolute risk reduction at 10 years per age group was the largest...


Radiotherapy and Oncology | 1997

Accelerated fractionation (AF) compared to conventional fractionation (CF) improves loco-regional control in the radiotherapy of advanced head and neck cancers: results of the EORTC 22851 randomized trial

Jean-Claude Horiot; P. Bontemps; Walter Van den Bogaert; René Le Fur; Danièle van den Weijngaert; Michel Bolla; Jacques Bernier; Antoine Lusinchi; Martin Stuschke; José Lopez-Torrecilla; Adrian C. Begg; M. Pierart; Laurence Collette

Abstract Background and purpose : A 5 week-hyperfractionated and accelerated radiotherapy regimen without reduction of the total dose was developed to fight tumour repopulation during treatment and tumour hypoxia. The purpose of the study was to try to improve loco-regional control in high risk head and neck carcinoma treated with curative radiotherapy. Methods and materials : From 1985 to 1995, a randomised controlled trial of the EORTC Cooperative Group of Radiotherapy (EORTC 22851) compared the experimental regimen (72 Gy45 fractions/5 weeks) to standard fractionation and overall treatment time (70 Gy35 fractions/7 weeks) in T2, T3 and T4 head and neck cancers (hypopharynx excluded). The end-point criteria were local and loco-regional control, overall and disease-free survival, and acute and late toxicities. Five hundred twelve patients were accrued. Results : Patients in the AF (accelerated fractionation) arm did significantly better with regard to loco-regional control ( P = 0.02) resulting at 5 years in a 13% gain (95% CI 3–23% gain) in loco-regional control over the CF (conventional fractionation) arm. This improvement is of larger magnitude in patients with poorer prognosis (N2–3 any T, T4 any N) than in patients with more favourable stage. Multivariate analysis confirmed AF as an independent prognostic factor of good prognosis for loco-regional control ( P = 0.03). Specific survival shows a trend ( P = 0.06) in favour of the AF arm. Acute and late toxicities : Acute and late toxicity were increased in the AF arm. Late severe functional irradiation damage occurred in 14% of patients of the AF arm versus 4% in the CF arm. Two cases of radiation-induced myelitis occurred after doses of 42 and 48 Gy to the spinal cord. Conclusions : This trial shows that accelerated radiotherapy improves loco-regional control in head and neck squamous cell carcinomas. A less toxic scheme should, however, be investigated and documented before using accelerated radiotherapy as a standard regimen of curative radiotherapy for head and neck cancers.


Cancer | 2006

Radiation-induced xerostomia in patients with head and neck cancer: a literature review.

Piet Dirix; Sandra Nuyts; Walter Van den Bogaert

A dry mouth or xerostomia is one of the most common complications during and after radiotherapy for head and neck cancer, because irreparable damage is caused to the salivary glands, which are included in the radiation fields. Xerostomia not only significantly impairs the quality of life of potentially cured cancer patients, it may also lead to severe and long‐term oral disorders. Because management of xerostomia is rarely effective, prevention is paramount. Several strategies have been developed to avoid radiation‐induced salivary dysfunction without compromising definitive oncologic treatment. These include salivary gland‐sparing radiation techniques, such as 3‐dimensional conformal or intensity‐modulated radiotherapy, concomitant cytoprotectants, and surgical salivary gland transfer. However, these preventive approaches are not applicable to all patients, and comprehensive scientific research that incorporates new biological insights is warranted to optimize the therapeutic index of radiotherapy for head and neck cancer. Cancer 2006.


Journal of Clinical Oncology | 2009

Impact of Pathological Characteristics on Local Relapse After Breast-Conserving Therapy: A Subgroup Analysis of the EORTC Boost Versus No Boost Trial

Heather A. Jones; Ninja Antonini; Augustinus A. M. Hart; Johannes L. Peterse; Jean-Claude Horiot; Françoise Collin; Philip Poortmans; S. Bing Oei; Laurence Collette; H. Struikmans; Walter Van den Bogaert; A. Fourquet; Jos J. Jager; Dominic Schinagl; Carla C. Wárlám-Rodenhuis; Harry Bartelink

PURPOSE To investigate the long-term impact of pathologic characteristics and an extra boost dose of 16 Gy on local relapse, for stage I and II invasive breast cancer patients treated with breast conserving therapy (BCT). PATIENTS AND METHODS In the European Organisation for Research and Treatment of Cancer boost versus no boost trial, after whole breast irradiation, patients with microscopically complete excision of invasive tumor, were randomly assigned to receive or not an extra boost dose of 16 Gy. For a subset of 1,616 patients central pathology review was performed. RESULTS The 10-year cumulative risk of local breast cancer relapse as a first event was not significantly influenced if the margin was scored negative, close or positive for invasive tumor or ductal carcinoma in situ according to central pathology review (log-rank P = .45 and P = .57, respectively). In multivariate analysis, high-grade invasive ductal carcinoma was associated with an increased risk of local relapse (P = .026; hazard ratio [HR], 1.67), as was age younger than 50 years (P < .0001; HR, 2.38). The boost dose of 16 Gy significantly reduced the local relapse rate (P = .0006; HR, 0.47). For patients younger than 50 years old and in patients with high grade invasive ductal carcinoma, the boost dose reduced the local relapse from 19.4% to 11.4% (P = .0046; HR, 0.51) and from 18.9% to 8.6% (P = .01; HR, 0.42), respectively. CONCLUSION Young age and high-grade invasive ductal cancer were the most important risk factors for local relapse, while margin status had no significant influence. A boost dose of 16 Gy significantly reduced the negative effects of both young age and high-grade invasive cancer.


International Journal of Radiation Oncology Biology Physics | 2003

Tumor perfusion rate determined noninvasively by dynamic computed tomography predicts outcome in head-and-neck cancer after radiotherapy

Robert Hermans; Martijn Meijerink; Walter Van den Bogaert; A. Rijnders; Caroline Weltens; Philippe Lambin

PURPOSE To investigate the value of CT-determined tumor perfusion as a predictive factor of local and regional failure and cause-specific survival in head-and-neck cancer treated by radiotherapy. MATERIALS AND METHODS In 105 patients, the perfusion of a primary head-and-neck squamous cell carcinoma was estimated using dynamic CT. A contrast agent bolus was rapidly injected i.v., while during the first pass a dynamic data acquisition was performed at the level of the largest axial tumor surface. The perfusion in the selected tumor region of interest was calculated by dividing the slope of the tumor-time density curve by the maximal value in arterial density. Primary and nodal tumor volume was calculated from the CT images. All patients were treated by radiotherapy with curative intent; in 15 patients, adjuvant concomitant chemotherapy was administered. Mean follow-up time was 2.2 years. Actuarial (life-table) statistical analysis was done; multivariate analysis was performed using the Cox proportional hazards model. RESULTS When the patients were stratified according to the median perfusion value (83.5 mL/min/100 g), those with the lower perfusion rate had a significantly higher local failure rate (p < 0.05). In the multivariate analysis, perfusion rate (p = 0.01) and T category (p = 0.03) were found to be the independent predictors of local failure. Perfusion rate had predictive value regarding neither regional control nor cause-specific survival. CONCLUSIONS CT-determined tumor perfusion rate was found to be an independent predictor of local outcome in irradiated head-and-neck cancer. The results of this study confirm the hypothesis that less-perfused tumors respond poorly to radiotherapy.


Radiotherapy and Oncology | 1987

Tumor excision and radiotherapy as primary treatment of breast cancer. Analysis of patient and treatment parameters and local control.

Erik Van Limbergen; Walter Van den Bogaert; Emmanuel van der Schueren; Alex Rijnders

From 1966 to 1979, 235 patients with operable breast cancer were treated by tumor excision and radiotherapy. The actuarial survival at 10 years was 94.8% for stage I and 58% for stage II tumors. Local recurrent cancer was seen in 23/235 patients and was related to T stage, N stage, width of surgical excision, radiation dose to the tumor bed and anatomopathological differentiation. Recurrences were seen in 1/7 of T0, 3/57 (5.2%) of T1, 11/102 (10.8%) of T2 and 2/6 of T3 tumors. Local control in the breast decreased significantly in N1b cases (p = 0.005) or when 3 or more axillary lymph nodes were positive (p = 0.0074). Local control after segmentectomy or tumorectomy was identical. However, a poorer local control was found in 20 cases treated with subtotal resection (p less than 0.05). A clear dose-local control relationship was found in this material, with a 100% local control in all T0, T1 tumors which received more than 1800 ret and all T2 tumors which received more than 2000 ret. As 19 of 23 breast recurrences were seen at the primary site in the breast we believe that booster doses should be given in order to maximise local control.


European Journal of Cancer | 2008

Predictors of the risk of fibrosis at 10 years after breast conserving therapy for early breast cancer - A study based on the EORTC trial 22881-10882 'boost versus no boost'

Sandra Collette; Laurence Collette; Tom Budiharto; Jean-Claude Horiot; Philip Poortmans; H. Struikmans; Walter Van den Bogaert; A. Fourquet; Jos J. Jager; W.J. Hoogenraad; Rolf-Peter Mueller; John M. Kurtz; D.A.L. Morgan; Jean-Bernard Dubois; Emile Salamon; René O. Mirimanoff; Michel Bolla; Marleen Van der Hulst; Carla C. Wárlám-Rodenhuis; Harry Bartelink

The EORTC 22881-10882 trial in 5178 conservatively treated early breast cancer patients showed that a 16 Gy boost dose significantly improved local control, but increased the risk of breast fibrosis. To investigate predictors for the long-term risk of fibrosis, Cox regression models of the time to moderate or severe fibrosis were developed on a random set of 1797 patients with and 1827 patients without a boost, and validated in the remaining set. The median follow-up was 10.7 years. The risk of fibrosis significantly increased (P<0.01) with increasing maximum whole breast irradiation (WBI) dose and with concomitant chemotherapy, but was independent of age. In the boost arm, the risk further increased (P<0.01) if patients had post-operative breast oedema or haematoma, but it decreased (P<0.01) if WBI was given with >6 MV photons. The c-index was around 0.62. Nomograms with these factors are proposed to forecast the long-term risk of moderate or severe fibrosis.


International Journal of Gynecological Cancer | 2009

Gynecologic cancers in pregnancy: guidelines of a second international consensus meeting.

Frédéric Amant; Kristel Van Calsteren; Michael Halaska; Jos H. Beijnen; Lieven Lagae; Myriam Hanssens; Liesbeth Heyns; Lore Lannoo; Nelleke Ottevanger; Walter Van den Bogaert; Laszlo Ungar; Ignace Vergote; Andreas du Bois

Objectives This study aimed to provide timely and effective guidance for pregnant women and health care providers to optimize maternal treatment and fetal protection and to promote effective management of the mother, fetus, and neonate when administering potentially teratogenic medications. New insights and more experience were gained since the first consensus meeting 5 years ago. Methods Members of the European Society of Gynecological Oncology task force “Cancer in Pregnancy” in concert with other international experts reviewed the existing literature on their respective areas of expertise. The summaries were subsequently merged into a complete article that served as a basis for discussion during the consensus meeting. All participants approved the final article. Results In the experts’ view, cancer can be successfully treated during pregnancy in collaboration with a multidisciplinary team, optimizing maternal treatment while considering fetal safety. To maximize the maternal outcome, cancer treatment should follow a standard treatment protocol as for nonpregnant patients. Iatrogenic prematurity should be avoided. Individualization of treatment and effective psychologic support is imperative to provide throughout the pregnancy period. Diagnostic procedures, including staging examinations and imaging, such as magnetic resonance imaging and sonography, are preferable. Pelvic surgery, either open or laparoscopic, as part of a treatment protocol, may reveal beneficial outcomes and is preferably performed by experts. Most standard regimens of chemotherapy can be administered from 14 weeks gestational age onward. Apart from cervical and vulvar cancer, as well as important vulvar scarring, the mode of delivery is determined by the obstetrician. Term delivery is aimed for. Breast-feeding should be considered based on individual drug safety and neonatologist–breast-feeding expert’s consult. Conclusions Despite limited evidence-based information, cancer treatment during pregnancy can succeed. State-of-the-art treatment should be provided for this vulnerable population to preserve maternal and fetal prognosis. Supplementary Information Supplementary data on teratogenic effects, ionizing examinations, sentinel lymph node biopsy, tumor markers during pregnancy, as well as additional references and tables are available at the extended online version of this consensus article, go to http://links.lww.com/IGC/A197.


Radiotherapy and Oncology | 2001

Interobserver variations in gross tumor volume delineation of brain tumors on computed tomography and impact of magnetic resonance imaging

Caroline Weltens; Johan Menten; Michel Feron; Erwin Bellon; Philippe Demaerel; Frederik Maes; Walter Van den Bogaert; Emmanuel van der Schueren

PURPOSE (1) To assess the interobserver variability of brain tumor delineation on computed tomography (CT). (2) To assess the impact of the addition of magnetic resonance imaging (MRI) information. METHODS Nine physicians were asked to delineate the gross tumor volume (GTV) of five patients with supratentorial inoperable brain tumors on CT scans and 2 weeks (or more) later on MRIs. The delineations were performed on a computer screen. During delineation on MRI, the registered CT images (without delineation) were displayed on the screen (MRI+CT). RESULTS A high interobserver variability in GTV delineation on CT is found: the ratio of the largest to the smallest defined volumes varies for the five patients by factors of resp. 2.8, 1.8, 1.8, 1.9 and 1.7. The interobserver variability is as large on MRI+CT as on CT alone (ratio largest/smallest volume: 2.4, 1.7, 1.9, 2.7 and 1.5). Volumes delineated on MRI+CT (mean: 69.6 cm(3)) are larger than on CT alone (mean: 59.5 cm(3)). Residual volumes (volume delineated on one image modality but not on the other) are >0 for CT alone and for MRI+CT. CONCLUSIONS A large interobserver variability in GTV delineation of brain tumors is demonstrated. The addition of MRI to CT does not reduce interobserver variability. GTVs delineated on MRI+CT are larger than on CT alone, but some volumes are delineated on CT and not on MRI. Therefore, a combination of the two image modalities is recommended for brain tumor delineation for treatment planning.

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Erik Van Limbergen

Katholieke Universiteit Leuven

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Caroline Weltens

Katholieke Universiteit Leuven

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Sandra Nuyts

Katholieke Universiteit Leuven

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Robert Hermans

Catholic University of Leuven

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Yolande Lievens

Ghent University Hospital

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Philip Poortmans

Radboud University Nijmegen

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Piet Dirix

Katholieke Universiteit Leuven

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Philippe Lambin

Maastricht University Medical Centre

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