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Featured researches published by Paul Meijnders.


Radiotherapy and Oncology | 2008

The conundrum of hodgkin lymphoma nodes: To be or not to be included in the involved node radiation fields. The EORTC-GELA lymphoma group guidelines

T. Girinsky; Lena Specht; Mithra Ghalibafian; Veronique Edeline; Guillaume Bonniaud; Richard W.M. van der Maazen; Berthe M.P. Aleman; A. Paumier; Paul Meijnders; Yolande Lievens; Evert M. Noordijk; Philip Poortmans

PURPOSE To develop easily applicable guidelines for the determination of initially involved lymph nodes to be included in the radiation fields. PATIENTS AND METHODS Patients with supra-diaphragmatic Hodgkin lymphoma. All the imaging procedures were carried out with patients in the treatment position. The prechemotherapy PET/CT was coregistered with the postchemotherapy CT simulation for planning purposes. Initially involved lymph nodes were determined on fused prechemotherapy CT and FDG-PET imaging data. The initial assessment was verified with the postchemotherapy CT scan. RESULTS The classic guidelines for determining the involvement of lymph nodes were not easily applicable and did not seem to reflect the exact extent of Hodgkin lymphoma. Three simple steps were used to pinpoint involved lymph nodes. First, FDG-PET scans were meticulously analysed to detect lymph nodes that were overlooked on CT imaging. Second, any morphological and/or functional asymmetry was sought on CT and FDG-PET scans. Third, a decrease in size or the disappearance of initially visible lymph nodes on the prechemotherapy CT scan as compared to the postchemotherapy CT scan was considered as surrogate proof of initial involvement. CONCLUSIONS All the radiological procedures should be performed on patients in the treatment position for proper coregistration. It is highly advisable that all CT and/or CT/PET scans be performed with IV contrast. Using the above-mentioned three simple guidelines, initially involved lymph nodes can be detected with very satisfactory accuracy. It is also emphasized that the classic guidelines (2, 3, 4) can always be used when deemed necessary.


Journal of Clinical Oncology | 2011

Parenthood in Survivors of Hodgkin Lymphoma: An EORTC-GELA General Population Case-Control Study

Marleen A.E. van der Kaaij; Natacha Heutte; Paul Meijnders; Edwige Abeilard-Lemoisson; Michele Spina; Lotte C. Moser; Anouk Allgeier; Bart Meulemans; Brice Dubois; Arnold Simons; Pieternella J. Lugtenburg; Berthe M.P. Aleman; Evert M. Noordijk; Christophe Fermé; José Thomas; Aspasia Stamatoullas; Christophe Fruchart; Pauline Brice; Isabelle Gaillard; Jeanette K. Doorduijn; Catherine Sebban; Wilma G.J.M. Smit; Serge Bologna; Judith M. Roesink; Francisca Ong; Marc André; John Raemaekers; Michel Henry-Amar; Hanneke C. Kluin-Nelemans

PURPOSE We investigated the impact of Hodgkin lymphoma (HL) on parenthood, including factors influencing parenthood probability, by comparing long-term HL survivors with matched general population controls. PATIENTS AND METHODS A Life Situation Questionnaire was sent to 3,604 survivors treated from 1964 to 2004 in successive clinical trials. Responders were matched with controls (1:3 or 4) for sex, country, education, and year of birth (10-year groups). Controls were given an artificial date of start of treatment equal to that of their matched case. The main end point was presence of biologic children after treatment, which was evaluated by using conditional logistic regression analysis. Logistic regression analysis was used to analyze factors influencing spontaneous post-treatment parenthood. RESULTS In all, 1,654 French and Dutch survivors were matched with 6,414 controls. Median follow-up was 14 years (range, 5 to 44 years). After treatment, the odds ratio (OR) for having children was 0.77 (95% CI, 0.68 to 0.87; P < .001) for survivors compared with controls. Of 898 survivors who were childless before treatment, 46.7% achieved post-treatment parenthood compared with 49.3% of 3,196 childless controls (OR, 0.87; P = .08). Among 756 survivors with children before treatment, 12.4% became parents after HL treatment compared with 22.2% of 3,218 controls with children before treatment (OR, 0.49; P < .001). Treatment with alkylating agents, second-line therapy, and age older than 35 years at treatment appeared to reduce the chances of spontaneous post-treatment parenthood. CONCLUSION Survivors of HL had slightly but significantly fewer children after treatment than matched general population controls. The difference concerned only survivors who had children before treatment and appears to have more personal than biologic reasons. The chance of successful post-treatment parenthood was 76%.


Human Reproduction | 2014

Cryopreservation, semen use and the likelihood of fatherhood in male Hodgkin lymphoma survivors: An EORTC-GELA lymphoma group cohort study

M.A.E. Van Der Kaaij; J. van Echten-Arends; Natacha Heutte; Paul Meijnders; Edwige Abeilard-Lemoisson; Michele Spina; Elizabeth C. Moser; Anouk Allgeier; Bart Meulemans; Pieternella J. Lugtenburg; Berthe M.P. Aleman; Evert M. Noordijk; Christophe Fermé; José Thomas; Aspasia Stamatoullas; Christophe Fruchart; Houchingue Eghbali; Pauline Brice; Wilma G.J.M. Smit; C. Sebban; J. Doorduijn; Judith M. Roesink; Isabelle Gaillard; Bertrand Coiffier; Marnix L.M. Lybeert; Olivier Casasnovas; Marc André; John Raemaekers; Michel Henry-Amar; J.C. Kluin-Nelemans

STUDY QUESTION How does the successful cryopreservation of semen affect the odds of post-treatment fatherhood among Hodgkin lymphoma (HL) survivors? SUMMARY ANSWER Among 334 survivors who wanted to have children, the availability of cryopreserved semen doubled the odds of post-treatment fatherhood. WHAT IS KNOWN ALREADY Cryopreservation of semen is the easiest, safest and most accessible way to safeguard fertility in male patients facing cancer treatment. Little is known about what proportion of patients achieve successful semen cryopreservation. To our knowledge, neither the factors which influence the occurrence of semen cryopreservation nor the rates of fatherhood after semen has been cryopreserved have been analysed before. STUDY DESIGN, SIZE, DURATION This is a cohort study with nested case-control analyses of consecutive Hodgkin survivors treated between 1974 and 2004 in multi-centre randomized controlled trials. A written questionnaire was developed and sent to 1849 male survivors. PARTICIPANTS/MATERIALS, SETTING, METHODS Nine hundred and two survivors provided analysable answers. The median age at treatment was 31 years. The median follow-up after cryopreservation was 13 years (range 5-36). MAIN RESULTS AND THE ROLE OF CHANCE Three hundred and sixty-three out of 902 men (40%) cryopreserved semen before the start of potentially gonadotoxic treatment. The likelihood of semen cryopreservation was influenced by age, treatment period, disease stage, treatment modality and education level. Seventy eight of 363 men (21%) used their cryopreserved semen. Men treated between 1994 and 2004 had significantly lower odds of cryopreserved semen use compared with those treated earlier, whereas alkylating or second-line (chemo)therapy significantly increased the odds of use; no other influencing factors were identified. We found an adjusted odds ratio of 2.03 (95% confidence interval 1.11-3.73, P = 0.02) for post-treatment fatherhood if semen cryopreservation was performed. Forty-eight out of 258 men (19%) who had children after HL treatment became a father using cryopreserved semen. LIMITATIONS, REASONS FOR CAUTION Data came from questionnaires and so this study potentially suffers from response bias. We could not perform an analysis with correction for duration of follow-up or provide an actuarial use rate due to lack of dates of semen utilization. We do not have detailed information on either the techniques used in cryopreserved semen utilization or the number of cycles needed. STUDY FUNDING/COMPETING INTERESTS Lance Armstrong Foundation, Dutch Cancer Foundation, René Vogels Stichting, no competing interests.


International Journal of Radiation Oncology Biology Physics | 2011

Retention of the In Vitro Radiosensitizing Potential of Gemcitabine Under Anoxic Conditions, in p53 Wild-Type and p53-Deficient Non-Small-Cell Lung Carcinoma Cells

A. N. Wouters; Bea Pauwels; Hilde A.J. Lambrechts; Greet G.O. Pattyn; Johan Ides; Marc Baay; Paul Meijnders; Marc Peeters; Jan B. Vermorken; Filip Lardon

PURPOSE Whereas radiosensitization by gemcitabine is well studied under normal oxygen conditions, little is known about its radiosensitizing potential under reduced oxygen conditions. Therefore, the present study evaluated the impact of anoxia on gemcitabine-mediated radiosensitization. METHODS AND MATERIALS The clonogenic assay was performed in three isogenic A549 cell lines differing in p53 status (24 h, 0-15 nM gemcitabine, 0-8 Gy irradiation, normoxia vs. anoxia). Using radiosensitizing conditions, cells were collected for cell cycle analysis and apoptosis detection. RESULTS Whereas wild-type p53 A549-LXSN cells were more sensitive to radiation than p53-deficient A549-E6 cells, both cell lines showed similar radiosensitization by gemcitabine under normoxia and anoxia. Independent of p53 functionality, gemcitabine was able to overcome anoxia-induced G(0/1) arrest and established an (early) S phase block in normoxic and anoxic cells. The percentage early and late apoptotic/necrotic cells increased with the gemcitabine/radiation combination, with a significant difference between A549-LXSN and A549-E6. CONCLUSIONS This study is the first to show that gemcitabine retains its radiosensitizing potential under low oxygen conditions. Although radiosensitization was observed in both p53 wild-type and p53-deficient cells, p53 status might influence induction of apoptosis after gemcitabine/radiation treatment, whereas no effect on cell cycle progression was noticed.


Radiation Oncology | 2016

Soft tissue sarcoma of the extremities: Pending questions on surgery and radiotherapy

Fien Hoefkens; Charlotte Dehandschutter; J. Somville; Paul Meijnders; Dirk Van Gestel

Soft tissue sarcomas are uncommon tumours of mesenchymal origin, most commonly arising in the extremities. Treatment includes surgical resection in combination with radiotherapy. Resection margins are of paramount importance in surgical treatment of soft tissue sarcomas but unambiguous guidelines for ideal margins of resection are still missing as is an uniform guideline on the use of radiotherapy.The present paper reviews the literature on soft tissue sarcomas of the extremities regarding the required resection margins, the impact of new radiotherapy techniques and the timing of radiotherapy, more particularly if it should be administered before or after surgical resection.This review was started by searching guidelines in different databases (National Guideline Clearinghouse, EBMPracticeNet, TRIP database, NCCN guidelines,…). After refinement of the query, more specific articles were found using MEDLINE, PubMed, Web of Science and Google Scholar. Used keywords include “soft tissue sarcoma”; “extremities OR limbs”; “radiotherapy”, “surgery”, “margins”, “local recurrence” and “overall survival”. Finally, the articles were selected based on the accessibility of the full text, use of the English language and relevance based on title and abstract.Literature demonstrates positive resection margins to be an important adverse prognostic factor for local recurrence of soft tissue sarcomas of the extremities. Still, no consensus is reached on the definition of what a good margin might be. The evolution of new radiation techniques, especially Intensity Modulated Radiotherapy, resulted in a s healthy surrounding tissues. However, the timing of radiotherapy treatment remains controversial as both preoperative and postoperative radiotherapy are characterised by several advantages and disadvantages.


British Journal of Haematology | 2017

Survival differences between patients with Hodgkin lymphoma treated inside and outside clinical trials. A study based on the EORTC-Netherlands Cancer Registry linked data with 20 years of follow-up

Lifang Liu; Francesco Giusti; Michael Schaapveld; Berthe M.P. Aleman; Pieternella J. Lugtenburg; Paul Meijnders; Martin Hutchings; Valery Lemmens; Jan Bogaerts; Otto Visser

The survival of patients diagnosed with Hodgkin lymphoma (HL) has improved from 70% to 90% in clinical trials. However, population‐based data has shown lower survival. In this study, clinical trial data were linked with cancer registry to identify trial and non‐trial participants and differences in overall survival and associated factors were assessed. In 1986–2004, 27% of HL patients aged 15–70 years participated in clinical trials. Compared to non‐trial participants, trial participants were younger (median age, 31 vs. 34 years), had staging registered more accurately and had an 8% higher 20‐year survival rate (73% vs. 65%). After adjusting for baseline differences, no differences in survival (hazard ratio = 0·96, 95% confidence interval 0·82–1·12), or in subgroup analysis according to stage, remained. Over time, increased administration of chemotherapy in combination with radiotherapy, together with the decreased use of radiotherapy alone was observed among the trial population. This trend was later followed in non‐trial participants, coinciding with a similar ‘take‐up’ in survival. The observed superior survival among patients with HL treated in clinical trials can be largely explained by the differences in baseline characteristics, particularly younger age. High trial participation rate and centralized expertise facilitates the implementation of trial findings to real‐world practice.


Acta Oncologica | 2017

Proposal for magnetic resonance imaging-guided salvage radiotherapy for prostate cancer

P. Dirix; Lien van Walle; Filip Deckers; François Van Mieghem; Guido Buelens; Paul Meijnders; P. Huget; Steven Van Laere

Abstract Background: A subset of patients experience a biochemical recurrence following radical prostatectomy. Radiotherapy can salvage those patients, provided that all disease is encompassed within the target volume. We hypothesized that this can be achieved more adequately with magnetic resonance imaging (MRI)-guided treatment planning. Material and methods: From January 2009 to April 2014, 183 patients were referred to our department for salvage radiotherapy (SRT). According to protocol, patients received a planning computed tomography (CT) as well as an MRI in treatment position. All MRI scans were retrospectively reviewed by an experienced uro-radiologist. Results: Median prostate-specific antigen (PSA) value at time of referral was 0.3 ng/ml (range 0.02–4.7 ng/ml). MRI did not show any suspected macroscopic disease in 137 patients (75%). In 46 (25%) patients, MRI did indicate a pelvic recurrence. The mean PSA level was significantly higher in patients with a suspected recurrence on MRI (0.4 vs. 1.4 ng/ml, p < .001) on a Student’s t-test. The mean follow-up was 33 months (range 5–69 months). Biochemical disease-free survival (bDFS) was significantly worse in patients with suspected disease on MRI [hazard ratio (HR) 2.9, p < .0001]. bDFS was significantly worse in the subgroup where the macroscopic recurrences on MRI received a lower radiation dose (HR 3.4, p = .01). Conclusion: MRI detects loco-regional disease in a substantial subset of patients with a biochemical recurrence after prostatectomy, especially in a PSA above 0.5 μg/l. Lack of MRI-based dose escalation on these macroscopic recurrences could explain some of the biochemical progression observed after SRT.


Radiation Oncology | 2018

A phase I dose-escalation trial of stereotactic ablative body radiotherapy for non-spine bone and lymph node metastases (DESTROY-trial)

Carole Mercier; P. Dirix; Paul Meijnders; Peter B. Vermeulen; Steven Van Laere; Hilde Debois; P. Huget; Dirk Verellen

BackgroundIn an oligometastatic setting, metastasis-directed treatment could render patients disease free, possibly for a protracted interval. Stereotactic ablative radiotherapy (SABR) is one of the treatment modalities that can be offered to these patients. In addition, the radiobiological qualities of SABR are promising for the use in perceived radioresistant tumours. There is also emerging evidence that SABR can stimulate the immune response, and a specific therapeutic window may exist for the optimal use of radiotherapy as an immune adjuvant. However, when SABR is considered for non-spine bone or lymph node metastases, the optimal fractionation schedule is not yet known.MethodsThe DESTROY-trial is a non-randomized prospective phase I trial determining a regimen of choice for patients with non-spine bone and lymph node metastases. A total of 90 patients will be included in three different treatment regimens. They will be offered stereotactic ablative radiotherapy in 5, 3 or 1 fractions. Dose-limiting toxicity will be recorded as primary endpoint. Acute and late toxicity, local response and local recurrence, and progression-free survival are secondary endpoints. Liquid biopsies will be collected throughout the course of this study from the second fractionation schedule on.DiscussionDespite its almost universal use in (oligo-)metastatic patients, the level of evidence supporting radical local treatment in general, and stereotactic radiotherapy in particular, is low. This prospective phase I trial will evaluate different SABR regimens for metastases and the differences in immune-stimulatory effects.Trial registrationThe Ethics committee of the GZA Hospitals (B099201732915) approved this study on 05/07/2017. Amendment for translational research was approved on 06/02/2018. Trial registered on Clinicaltrials.gov (NCT03486431) on 03/04/2018 – Retrospectively registered.


Hematological Oncology | 2017

CARDIAC DISEASE PREDICTION FOLLOWING HODGKIN LYMPHOMA: AN EORTC LYMPHOMA GROUP AND GELA FOLLOW-UP STUDY

Maja V. Maraldo; Francesco Giusti; M.A.E. Van Der Kaaij; Michel Henry-Amar; Berthe M.P. Aleman; John Raemaekers; Paul Meijnders; Elizabeth C. Moser; Hanneke C. Kluin-Nelemans; Michele Spina; Christophe Fermé; Catherine Fortpied; Lena Specht

174 CARDIAC DISEASE PREDICTION FOLLOWING HODGKIN LYMPHOMA: AN EORTC LYMPHOMA GROUP AND GELA FOLLOW‐UP STUDY M.V. Maraldo* | F. Giusti | M.A. van der Kaaij | M. Henry‐Amar | B. Aleman | J. Raemaekers | P. Meijnders | E.C. Moser | H.C. Kluin‐Nelemans | M. Spina | C. Ferme | C. Fortpied | L. Specht Department of Clinical Oncology, Rigshospitalet, Copenhagen, Denmark; Department of Statistics, EORTC Headquarters, Brussels, Belgium; Department of Internal Medicine, VU University Medical Centre, Amsterdam, Netherlands; Centre de Traitement des Données du Cancéropôle Nord‐Ouest, Centre François Baclesse, Caen, France; Department of Radiation Oncology, the Netherlands Cancer Institute, Amsterdam, Netherlands; Department of Hematology, Radboud University Medical Center, Nijmegen, Netherlands; Department of Radiation Oncology, Iridium Cancer Network, University of Antwerp, Antwerp, Belgium; Department of Radiation Oncology, Champalimaud Cancer Centre, Lisbon, Portugal; Department of Hematology, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands; Division of Medical Oncology, National Cancer Institute, Aviano, Italy; Department of Hematology, Institut Gustave Roussy, Villejuif, France


Acta Oncologica | 2017

Interobserver delineation uncertainty in involved-node radiation therapy (INRT) for early-stage Hodgkin lymphoma: on behalf of the Radiotherapy Committee of the EORTC lymphoma group

Marianne C. Aznar; T. Girinsky; Anne Kiil Berthelsen; Berthe M.P. Aleman; Max Beijert; Martin Hutchings; Yolande Lievens; Paul Meijnders; Peter Meidahl Petersen; Deborah A. Schut; Maja V. Maraldo; Richard W.M. van der Maazen; Lena Specht

Abstract Background and purpose: In early-stage classical Hodgkin lymphoma (HL) the target volume nowadays consists of the volume of the originally involved nodes. Delineation of this volume on a post-chemotherapy CT-scan is challenging. We report on the interobserver variability in target volume definition and its impact on resulting treatment plans. Materials and methods: Two representative cases were selected (1: male, stage IB, localization: left axilla; 2: female, stage IIB, localizations: mediastinum and bilateral neck). Eight experienced observers individually defined the clinical target volume (CTV) using involved-node radiotherapy (INRT) as defined by the EORTC-GELA guidelines for the H10 trial. A consensus contour was generated and the standard deviation computed. We investigated the overlap between observer and consensus contour [Sørensen-Dice coefficient (DSC)] and the magnitude of gross deviations between the surfaces of the observer and consensus contour (Hausdorff distance). 3D-conformal (3D-CRT) and intensity-modulated radiotherapy (IMRT) plans were calculated for each contour in order to investigate the impact of interobserver variability on each treatment modality. Similar target coverage was enforced for all plans. Results: The median CTV was 120 cm3 (IQR: 95–173 cm3) for Case 1, and 255 cm3 (IQR: 183–293 cm3) for Case 2. DSC values were generally high (>0.7), and Hausdorff distances were about 30 mm. The SDs between all observer contours, providing an estimate of the systematic error associated with delineation uncertainty, ranged from 1.9 to 3.8 mm (median: 3.2 mm). Variations in mean dose resulting from different observer contours were small and were not higher in IMRT plans than in 3D-CRT plans. Conclusions: We observed considerable differences in target volume delineation, but the systematic delineation uncertainty of around 3 mm is comparable to that reported in other tumour sites. This report is a first step towards calculating an evidence-based planning target volume margin for INRT in HL.

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Berthe M.P. Aleman

Netherlands Cancer Institute

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John Raemaekers

Radboud University Nijmegen

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Evert M. Noordijk

Leiden University Medical Center

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