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Featured researches published by Jan Willem Leer.


Annals of Surgery | 2007

The TME trial after a median follow-up of 6 years - Increased local control but no survival benefit in irradiated patients with resectable rectal carcinoma

Koen C.M.J. Peeters; Corrie A.M. Marijnen; Iris D. Nagtegaal; Elma Klein Kranenbarg; Hein Putter; Theo Wiggers; Harm Rutten; Lars Påhlman; Bengt Glimelius; Jan Willem Leer; Cornelis J. H. van de Velde

Objective:To investigate the efficacy of preoperative short-term radiotherapy in patients with mobile rectal cancer undergoing total mesorectal excision (TME) surgery. Summary Background Data:Local recurrence is a major problem in rectal cancer treatment. Preoperative short-term radiotherapy has shown to improve local control and survival in combination with conventional surgery. The TME trial investigated the value of this regimen in combination with total mesorectal excision. Long-term results are reported after a median follow-up of 6 years. Methods:One thousand eight hundred and sixty-one patients with resectable rectal cancer were randomized between TME preceded by 5 × 5 Gy or TME alone. No chemotherapy was allowed. There was no age limit. Surgery, radiotherapy, and pathologic examination were standardized. Primary endpoint was local control. Results:Median follow-up of surviving patients was 6.1 year. Five-year local recurrence risk of patients undergoing a macroscopically complete local resection was 5.6% in case of preoperative radiotherapy compared with 10.9% in patients undergoing TME alone (P < 0.001). Overall survival at 5 years was 64.2% and 63.5%, respectively (P = 0.902). Subgroup analyses showed significant effect of radiotherapy in reducing local recurrence risk for patients with nodal involvement, for patients with lesions between 5 and 10 cm from the anal verge, and for patients with uninvolved circumferential resection margins. Conclusions:With increasing follow-up, there is a persisting overall effect of preoperative short-term radiotherapy on local control in patients with clinically resectable rectal cancer. However, there is no effect on overall survival. Since survival is mainly determined by distant metastases, efforts should be directed towards preventing systemic disease.


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.


International Journal of Radiation Oncology Biology Physics | 1996

Local irradiation alone for peripheral Stage I lung cancer: Could we omit the elective regional nodal irradiation?

Augustinus D.G. Krol; Peter Aussems; Evert M. Noordijk; Jo Hermans; Jan Willem Leer

PURPOSE The results of local irradiation only for patients with Stage I lung cancer were analyzed to see whether the treatment of regional lymph nodes could be omitted. METHODS AND MATERIALS One hundred and eight medically inoperable patients with nonsmall cell lung cancer (T1 and peripheral T2) were treated with 60 Gy split course or 65 Gy continuous treatment. The target volume included the primary tumor only, without regional lymph nodes. Response, survival, and patterns of failure were analyzed. RESULTS The overall response rate was 85% with 50 (46%) complete responses (CRs). Overall survival at 3 and 5 years was 31 and 15%, and cancer-specific survival was 42 and 31% at 3 and 5 years, respectively. The actuarial 5 years local relapse free survival in patients with a CR was 52%. Tumor size (< or = 4 cm) was strongly correlated with the chance of complete remission and better survival. Of patients in complete remission, only two had a regional recurrence as the only site of relapse; an additional two patients had a locoregional recurrence. CONCLUSION High-dose local radiotherapy on the primary tumor only is justified for medically inoperable patients with peripherally located nonsmall lung cancer. The low regional relapse rate does not support the need for the use of large fields encompassing regional lymph nodes. Using small target volumes, higher doses can be given and better local control rates can be expected.


Cancer | 2005

Prediction of survival in patients with metastases in the spinal column: results based on a randomized trial of radiotherapy.

Yvette M. van der Linden; Sander Dijkstra; Ernest Vonk; Corrie A.M. Marijnen; Jan Willem Leer

Adequate prediction of survival is important in deciding on treatment for patients with symptomatic spinal metastases. The authors reviewed 342 patients with painful spinal metastases without neurologic impairment who were treated conservatively within a large, prospectively randomized radiotherapy trial. Response to radiotherapy and prognostic factors for survival were studied.


Radiotherapy and Oncology | 1995

Quality assurance in radiotherapy: European Society for Therapeutic Radiology and Oncology Advisory Report to the Commission of the European Union for the ‘Europe Against Cancer Programme’☆

David I. Thwaites; Pierre Scalliet; Jan Willem Leer; Jens Overgaard

This document is now in the process of being endorsed by all National Scientific Societies of Radiotherapy and Medical Physics of the European countries. It can therefore not be formally considered as the definitive version and is still susceptible to benefit from further alterations or improvements.


Annals of Oncology | 2015

Adjuvant chemotherapy for rectal cancer patients treated with preoperative (chemo)radiotherapy and total mesorectal excision: a Dutch Colorectal Cancer Group (DCCG) randomized phase III trial

Anne J Breugom; W. van Gijn; E. W. Muller; Åke Berglund; C.B.M. van den Broek; Tone Fokstuen; Hans Gelderblom; Ellen Kapiteijn; Jan Willem Leer; Corrie A.M. Marijnen; Hendrik Martijn; E. Meershoek-Klein Kranenbarg; Iris D. Nagtegaal; Lars Påhlman; C.J.A. Punt; Hein Putter; A. G. H. Roodvoets; H.J.T. Rutten; W. H. Steup; Bengt Glimelius; C.J.H. van de Velde

BACKGROUND The discussion on the role of adjuvant chemotherapy for rectal cancer patients treated according to current guidelines is still ongoing. A multicentre, randomized phase III trial, PROCTOR-SCRIPT, was conducted to compare adjuvant chemotherapy with observation for rectal cancer patients treated with preoperative (chemo)radiotherapy and total mesorectal excision (TME). PATIENTS AND METHODS The PROCTOR-SCRIPT trial recruited patients from 52 hospitals. Patients with histologically proven stage II or III rectal adenocarcinoma were randomly assigned (1:1) to observation or adjuvant chemotherapy after preoperative (chemo)radiotherapy and TME. Radiotherapy consisted of 5 × 5 Gy. Chemoradiotherapy consisted of 25 × 1.8-2 Gy combined with 5-FU-based chemotherapy. Adjuvant chemotherapy consisted of 5-FU/LV (PROCTOR) or eight courses capecitabine (SCRIPT). Randomization was based on permuted blocks of six, stratified according to centre, residual tumour, time between last irradiation and surgery, and preoperative treatment. The primary end point was overall survival. RESULTS Of 470 enrolled patients, 437 were eligible. The trial closed prematurely because of slow patient accrual. Patients were randomly assigned to observation (n = 221) or adjuvant chemotherapy (n = 216). After a median follow-up of 5.0 years, 5-year overall survival was 79.2% in the observation group and 80.4% in the chemotherapy group [hazard ratio (HR) 0.93, 95% confidence interval (CI) 0.62-1.39; P = 0.73]. The HR for disease-free survival was 0.80 (95% CI 0.60-1.07; P = 0.13). Five-year cumulative incidence for locoregional recurrences was 7.8% in both groups. Five-year cumulative incidence for distant recurrences was 38.5% and 34.7%, respectively (P = 0.39). CONCLUSION The PROCTOR-SCRIPT trial could not demonstrate a significant benefit of adjuvant chemotherapy with fluoropyrimidine monotherapy after preoperative (chemo)radiotherapy and TME on overall survival, disease-free survival, and recurrence rate. However, this trial did not complete planned accrual. REGISTRATION NUMBER Dutch Colorectal Cancer group, CKTO 2003-16, ISRCTN36266738.


Radiotherapy and Oncology | 1988

The effect of radiotherapy on dysphagia and survival in patients with esophageal cancer

Robert J.L. Caspers; Kees Welvaart; Robbert J. Verkes; Jo Hermans; Jan Willem Leer

A group of 127 patients with esophageal cancer treated with radiotherapy at different dose levels was retrospectively analysed. It was found that 70.5% of the patients showed improvement of dysphagia and that 54% remained palliated with respect to food passage until their death. The two major prognostic variables with respect to the palliative effect on dysphagia as well as survival were the passage score and the radiation dose. Patients with severe dysphagia (PASS 0 or 1) had a median actuarial DFI and SURV of 3.7 and 6.4 months, respectively, in contrast to 16.0 and 8.7 months for patients who were able to use (semi)solid food (PASS 2 and 3). The median actuarial DFI and SURV of patients treated with a relatively low dose (less than 50 Gy in 5 weeks) were 2.5 and 4.8 months, respectively, compared to 10.1 and 8.3 months, respectively, for patients treated with a relatively high dose.


Radiotherapy and Oncology | 2008

Evidence and research in rectal cancer

Vincenzo Valentini; Regina G. H. Beets-Tan; Josep M. Borràs; Zoran Krivokapic; Jan Willem Leer; Lars Påhlman; Claus Rödel; Hans-Joachim Schmoll; Nigel Scott; Cornelius J.H. van de Velde; Christine Verfaillie

The main evidences of epidemiology, diagnostic imaging, pathology, surgery, radiotherapy, chemotherapy and follow-up are reviewed to optimize the routine treatment of rectal cancer according to a multidisciplinary approach. This paper reports on the knowledge shared between different specialists involved in the design and management of the multidisciplinary ESTRO Teaching Course on Rectal Cancer. The scenario of ongoing research is also addressed. In this time of changing treatments, it clearly appears that a common standard for large heterogeneous patient groups have to be substituted by more individualised therapies based on clinical-pathological features and very soon on molecular and genetic markers. Only trained multidisciplinary teams can face this new challenge and tailor the treatments according to the best scientific evidence for each patient.


Radiotherapy and Oncology | 1998

Indications and treatment schedules for irradiation of benign diseases: a survey

Jan Willem Leer; Paul Van Houtte; Jaap Davelaar

BACKGROUND The interest in the treatment of benign diseases with radiotherapy has grown particularly in the Western part of the world. Questions about the effectiveness and risks of radiotherapy for these disorders have to be answered in the light of new information from clinical research, dose calculations and risk estimates. New indications for irradiation of non-malignant diseases, e.g. vascular disorders, such as macular degeneration and prevention of stent restenosis, are appearing. As a starting point for further discussions and publications in this area, the authors, with the help of the European Society for Therapeutic Radiology and Oncology (ESTRO), performed a survey of current practice and of opinion amongst ESTRO members. METHODS A questionnaire was circulated in 1996 to 1348 institutes listed in the 1995 ESTRO directory asking whether the respondents considered a list of the 28 most common benign disorders as being a good indication for radiotherapy. Details of the frequency of such treatments and of treatment schedules used were requested. RESULTS AND CONCLUSIONS A large variation in indications and treatment schedules was detected throughout the world. This variation confirms the inadequate information on which such treatments are based and stresses the importance of careful clinical studies and trials as well as clear understanding of any risks involved.


International Journal of Radiation Oncology Biology Physics | 2009

Radiotherapy and Hyperthermia for Treatment of Primary Locally Advanced Cervix Cancer: Results in 378 Patients

Martine Franckena; Ludy Lutgens; Peter C.M. Koper; Catharina E. Kleynen; Elsbieta M. van der Steen-Banasik; Jan J. Jobsen; Jan Willem Leer; Carien L. Creutzberg; Michel F.H. Dielwart; Yvette van Norden; Richard Canters; Gerard C. van Rhoon; Jacoba van der Zee

PURPOSE To report response rate, pelvic tumor control, survival, and late toxicity after treatment with combined radiotherapy and hyperthermia (RHT) for patients with locally advanced cervical carcinoma (LACC) and compare the results with other published series. METHODS AND MATERIALS From 1996 to 2005, a total of 378 patients with LACC (International Federation of Gynecology and Obstetrics Stage IB2-IVA) were treated with RHT. External beam radiotherapy (RT) was applied to 46-50.4 Gy and combined with brachytherapy. The hyperthermia (HT) was prescribed once weekly. Primary end points were complete response (CR) and local control. Secondary end points were overall survival, disease-specific survival, and late toxicity. Patient, tumor, and treatment characteristics predictive for the end points were identified in univariate and multivariate analyses. RESULTS Overall, a CR was achieved in 77% of patients. At 5 years, local control, disease-specific survival, and incidence of late toxicity Common Terminology Criteria for Adverse Events Grade 3 or higher were 53%, 47%, and 12%, respectively. In multivariate analysis, number of HT treatments emerged as a predictor of outcome in addition to commonly identified prognostic factors. CONCLUSIONS The CR, local control, and survival rates are similar to previously observed results of RHT in the randomized Dutch Deep Hyperthermia Trial. Reported treatment results for currently applied combined treatment modalities (i.e., RT with chemotherapy and/or HT) do not permit definite conclusions about which combination is superior. The present results confirm previously shown beneficial effects from adding HT to RT and justify the application of RHT as first-line treatment in patients with LACC as an alternative to chemoradiation.

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Corrie A.M. Marijnen

Leiden University Medical Center

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Yvette M. van der Linden

Leiden University Medical Center

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Andries G. Visser

Radboud University Nijmegen Medical Centre

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Elsbeth Steenland

Leiden University Medical Center

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Gijs Bleijenberg

Radboud University Nijmegen

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