Liesbeth Boersma
Maastricht University Medical Centre
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Featured researches published by Liesbeth Boersma.
Journal of Clinical Oncology | 2006
Dirk De Ruysscher; Madelon Pijls-Johannesma; Søren M. Bentzen; A. Minken; Rinus Wanders; Ludy Lutgens; Monique Hochstenbag; Liesbeth Boersma; Bradly G. Wouters; Guido Lammering; Johan Vansteenkiste; Philippe Lambin
PURPOSE To identify time factors for combined chemotherapy and radiotherapy predictive for long-term survival of patients with limited-disease small-cell lung cancer (LD-SCLC). METHODS A systematic overview identified suitable phase III trials. Using meta-analysis methodology to compare results within trials, the influence of the timing of chest radiation and the start of any treatment until the end of radiotherapy (SER) on local tumor control, survival, and esophagitis was analyzed. For comparison between studies, the equivalent radiation dose in 2-Gy fractions, corrected for the overall treatment time of chest radiotherapy, was analyzed. RESULTS The SER was the most important predictor of outcome. There was a significantly higher 5-year survival rate in the shorter SER arms (relative risk [RR] = 0.62; 95% CI, 0.49 to 0.80; P = .0003), which was more than 20% when the SER was less than 30 days (upper bound of 95% CI, 90 days). A low SER was associated with a higher incidence of severe esophagitis (RR = 0.55; 95% CI, 0.42 to 073; P < .0001). Each week of extension of the SER beyond that of the study arm with the shortest SER resulted in an overall absolute decrease in the 5-year survival rate of 1.83% +/- 0.18% (95% CI). CONCLUSION A low time between the first day of chemotherapy and the last day of chest radiotherapy is associated with improved survival in LD-SCLC patients. The novel parameter SER, which takes into account accelerated proliferation of tumor clonogens during both radiotherapy and chemotherapy, may facilitate a more rational design of combined-modality treatment in rapidly proliferating tumors.
Journal of Clinical Oncology | 2010
Angela van Baardwijk; S Wanders; Liesbeth Boersma; Jacques Borger; Michel Öllers; Anne-Marie C. Dingemans; Gerben Bootsma; Wiel Geraedts; Cordula Pitz; Ragnar Lunde; Philippe Lambin; Dirk De Ruysscher
PURPOSE We previously showed that individualized radiation dose escalation based on normal tissue constraints would allow safe administration of high radiation doses with low complication rate. Here, we report the mature results of a prospective, single-arm study that used this individualized tolerable dose approach. PATIENTS AND METHODS In total, 166 patients with stage III or medically inoperable stage I to II non-small-cell lung cancer, WHO performance status 0 to 2, a forced expiratory volume at 1 second and diffusing capacity of lungs for carbon monoxide >or= 30% were included. Patients were irradiated using an individualized prescribed total tumor dose (TTD) based on normal tissue dose constraints (mean lung dose, 19 Gy; maximal spinal cord dose, 54 Gy) up to a maximal TTD of 79.2 Gy in 1.8 Gy fractions twice daily. Only sequential chemoradiation was administered. The primary end point was overall survival (OS), and the secondary end point was toxicity according to Common Terminology Criteria of Adverse Events (CTCAE) v3.0. RESULTS The median prescribed TTD was 64.8 Gy (standard deviation, +/- 11.4 Gy) delivered in 25 +/- 5.8 days. With a median follow-up of 31.6 months, the median OS was 21.0 months with a 1-year OS of 68.7% and a 2-year OS of 45.0%. Multivariable analysis showed that only a large gross tumor volume significantly decreased OS (P < .001). Both acute (grade 3, 21.1%; grade 4, 2.4%) and late toxicity (grade 3, 4.2%; grade 4, 1.8%) were acceptable. CONCLUSION Individualized prescribed radical radiotherapy based on normal tissue constraints with sequential chemoradiation shows survival rates that come close to results of concurrent chemoradiation schedules, with acceptable acute and late toxicity. A prospective randomized study is warranted to further investigate its efficacy.
International Journal of Radiation Oncology Biology Physics | 2010
Judith van Loon; Dirk De Ruysscher; Rinus Wanders; Liesbeth Boersma; Jean Simons; Michel Oellers; Anne-Marie C. Dingemans; Monique Hochstenbag; Gerben Bootsma; Wiel Geraedts; Cordula Pitz; Jaap Teule; Ali Rhami; Willy Thimister; Gabriel Snoep; Cary Dehing-Oberije; Philippe Lambin
PURPOSE To evaluate the results of selective nodal irradiation on basis of (18)F-deoxyglucose positron emission tomography (PET) scans in patients with limited-disease small-cell lung cancer (LD-SCLC) on isolated nodal failure. METHODS AND MATERIALS A prospective study was performed of 60 patients with LD-SCLC. Radiotherapy was given to a dose of 45 Gy in twice-daily fractions of 1.5 Gy, concurrent with carboplatin and etoposide chemotherapy. Only the primary tumor and the mediastinal lymph nodes involved on the pretreatment PET scan were irradiated. A chest computed tomography (CT) scan was performed 3 months after radiotherapy completion and every 6 months thereafter. RESULTS A difference was seen in the involved nodal stations between the pretreatment (18)F-deoxyglucose PET scans and computed tomography scans in 30% of patients (95% confidence interval, 20-43%). Of the 60 patients, 39 (65%; 95% confidence interval [CI], 52-76%) developed a recurrence; 2 patients (3%, 95% CI, 1-11%) experienced isolated regional failure. The median actuarial overall survival was 19 months (95% CI, 17-21). The median actuarial progression-free survival was 14 months (95% CI, 12-16). 12% (95% CI, 6-22%) of patients experienced acute Grade 3 (Common Terminology Criteria for Adverse Events, version 3.0) esophagitis. CONCLUSION PET-based selective nodal irradiation for LD-SCLC resulted in a low rate of isolated nodal failures (3%), with a low percentage of acute esophagitis. These findings are in contrast to those from our prospective study of CT-based selective nodal irradiation, which resulted in an unexpectedly high percentage of isolated nodal failures (11%). Because of the low rate of isolated nodal failures and toxicity, we believe that our data support the use of PET-based SNI for LD-SCLC.
Radiotherapy and Oncology | 2013
Philippe Lambin; Erik Roelofs; Bart Reymen; Emmanuel Rios Velazquez; J. Buijsen; C.M.L. Zegers; S. Carvalho; R. Leijenaar; Georgi Nalbantov; Cary Oberije; M. Scott Marshall; Frank Hoebers; Esther G.C. Troost; Ruud G.P.M. van Stiphout; Wouter van Elmpt; Trudy van der Weijden; Liesbeth Boersma; Vincenzo Valentini; Andre Dekker
PURPOSE An overview of the Rapid Learning methodology, its results, and the potential impact on radiotherapy. MATERIAL AND RESULTS Rapid Learning methodology is divided into four phases. In the data phase, diverse data are collected about past patients, treatments used, and outcomes. Innovative information technologies that support semantic interoperability enable distributed learning and data sharing without additional burden on health care professionals and without the need for data to leave the hospital. In the knowledge phase, prediction models are developed for new data and treatment outcomes by applying machine learning methods to data. In the application phase, this knowledge is applied in clinical practice via novel decision support systems or via extensions of existing models such as Tumour Control Probability models. In the evaluation phase, the predictability of treatment outcomes allows the new knowledge to be evaluated by comparing predicted and actual outcomes. CONCLUSION Personalised or tailored cancer therapy ensures not only that patients receive an optimal treatment, but also that the right resources are being used for the right patients. Rapid Learning approaches combined with evidence based medicine are expected to improve the predictability of outcome and radiotherapy is the ideal field to study the value of Rapid Learning. The next step will be to include patient preferences in the decision making.
Radiotherapy and Oncology | 2015
Birgitte Vrou Offersen; Liesbeth Boersma; C. Kirkove; S. Hol; Marianne C. Aznar; Albert Biete Sola; Youlia M. Kirova; Jean-Philippe Pignol; Vincent Remouchamps; K. Verhoeven; Caroline Weltens; Meritxell Arenas; Dorota Gabrys; Neil Kopek; Mechthild Krause; Dan Lundstedt; Tanja Marinko; Angel Montero; John Yarnold; Philip Poortmans
BACKGROUND AND PURPOSE Delineation of clinical target volumes (CTVs) is a weak link in radiation therapy (RT), and large inter-observer variation is seen in breast cancer patients. Several guidelines have been proposed, but most result in larger CTVs than based on conventional simulator-based RT. The aim was to develop a delineation guideline obtained by consensus between a broad European group of radiation oncologists. MATERIAL AND METHODS During ESTRO teaching courses on breast cancer, teachers sought consensus on delineation of CTV through dialogue based on cases. One teacher delineated CTV on CT scans of 2 patients, followed by discussion and adaptation of the delineation. The consensus established between teachers was sent to other teams working in the same field, both locally and on a national level, for their input. This was followed by developing a broad consensus based on discussions. RESULTS Borders of the CTV encompassing a 5mm margin around the large veins, running through the regional lymph node levels were agreed, and for the breast/thoracic wall other vessels were pointed out to guide delineation, with comments on margins for patients with advanced breast cancer. CONCLUSION The ESTRO consensus on CTV for elective RT of breast cancer, endorsed by a broad base of the radiation oncology community, is presented to improve consistency.
International Journal of Radiation Oncology Biology Physics | 2008
Angela van Baardwijk; Geert Bosmans; Søren M. Bentzen; Liesbeth Boersma; Andre Dekker; Rinus Wanders; Bradly G. Wouters; Philippe Lambin; Dirk De Ruysscher
PURPOSE Local tumor recurrence remains a major problem in patients with inoperable non-small-cell lung cancer undergoing radiotherapy. We investigated the theoretical gain in the estimated tumor control probability (TCP) using an individualized maximal tolerable dose (MTD) prescription, for both conventional and accelerated fractionation schemes. METHODS AND MATERIALS For 64 non-small-cell lung cancer patients, five treatment plans were compared, dependent on the normal tissue dose constraints for the lung and spinal cord. The first two used a classic fractionation (2 Gy/d, 5 d/wk) to a total dose of 60 Gy (QD(classic)) or determined by the individualized MTD (QD(MTD)). The third scheme assumed a hypofractionated schedule of 2.75-Gy fractions (QD(hypofr)). The fourth and fifth assumed hyperfractionation and acceleration (1.8 Gy twice daily, either BID(classic) or BID(MTD)). The TCPs for the groups of patients were estimated. RESULTS The mean biologic equivalent dose in 2-Gy fractions for tumor, corrected for accelerated repopulation was significantly greater for the BID(MTD) scheme (62.1 Gy) than for any other scheme (QD(classic), 47.5 Gy; QD(MTD), 52.0 Gy; QD(hypofr), 56.9 Gy; and BID(classic), 56.9 Gy; p < 0.001). Although both dose-escalation (QD(MTD)) and hypofractionation (QD(hypofr)) resulted in an increase in the mean estimated TCP of 5.6% (p < 0.001) and 14.6% (p < 0.001), respectively, compared with QD(classic), the combination of escalation and acceleration (BID(MTD)) improved the mean estimated TCP by 26.4% (p < 0.001). CONCLUSION The results of this planning study showed a large gain in the estimated TCP using an MTD scheme with 1.8-Gy fractions BID compared with other fractionation schedules. Clinical studies implementing this concept are ongoing.
BMC Cancer | 2010
Merel Kimman; Monique M.F. Bloebaum; Carmen D. Dirksen; Ruud Houben; Philippe Lambin; Liesbeth Boersma
BackgroundCurrent frequent follow-up after treatment for breast cancer does not meet its intended aims, but does depend on expensive and scarce specialized knowledge for routine history taking and physical examinations. The study described in this paper compared patient satisfaction with a reduced follow-up strategy, i.e. nurse-led telephone follow-up, to satisfaction with traditional hospital follow-up.MethodsPatient satisfaction was assessed among patients (n = 299) who were participants of a randomized controlled trial investigating the cost-effectiveness of several follow-up strategies in the first year after treatment for breast cancer. Data on patient satisfaction were collected at baseline, three, six and 12 months after treatment, using the Dutch version of Wares Patient Satisfaction Questionnaire III (PSQ III). In addition to general satisfaction, the PSQ III reports on satisfaction scores for technical competence, interpersonal aspects, and access of care. Regression analysis was used to predict satisfaction scores from whether or not nurse-led telephone follow-up was received.ResultsNurse-led telephone follow-up had no statistically significant influence on general patient satisfaction (p = 0.379), satisfaction with technical competence (p = 0.249), and satisfaction with interpersonal aspects (p = 0.662). Regarding access of care, patient satisfaction scores were significantly higher for patients receiving telephone follow-up (p = 0.015). However, a mean difference at 12 months of 3.1 points was judged to be not clinically relevant.ConclusionsNo meaningful differences were found in satisfaction scores between nurse-led telephone and hospital follow-up in the first year after breast cancer treatment. With high satisfaction scores and the potential to substantially reduce clinic visits, nurse-led telephone follow-up may be an acceptable alternative to traditional hospital follow-up.Trial registration numberISRCTN 74071417.
International Journal of Radiation Oncology Biology Physics | 2008
Angela van Baardwijk; Geert Bosmans; Liesbeth Boersma; S Wanders; Andre Dekker; Anne-Marie C. Dingemans; Gerben Bootsma; Wiel Geraedts; Cordula Pitz; Jean Simons; Philippe Lambin; Dirk De Ruysscher
PURPOSE Local recurrence is a major problem after (chemo-)radiation for non-small-cell lung cancer. We hypothesized that for each individual patient, the highest therapeutic ratio could be achieved by increasing total tumor dose (TTD) to the limits of normal tissues, delivered within 5 weeks. We report first results of a prospective feasibility trial. METHODS AND MATERIALS Twenty-eight patients with medically inoperable or locally advanced non-small-cell lung cancer, World Health Organization performance score of 0-1, and reasonable lung function (forced expiratory volume in 1 second > 50%) were analyzed. All patients underwent irradiation using an individualized prescribed TTD based on normal tissue dose constraints (mean lung dose, 19 Gy; maximal spinal cord dose, 54 Gy) up to a maximal TTD of 79.2 Gy in 1.8-Gy fractions twice daily. No concurrent chemoradiation was administered. Toxicity was scored using the Common Terminology Criteria for Adverse Events criteria. An (18)F-fluoro-2-deoxy-glucose-positron emission tomography-computed tomography scan was performed to evaluate (metabolic) response 3 months after treatment. RESULTS Mean delivered dose was 63.0 +/- 9.8 Gy. The TTD was most often limited by the mean lung dose (32.1%) or spinal cord (28.6%). Acute toxicity generally was mild; only 1 patient experienced Grade 3 cough and 1 patient experienced Grade 3 dysphagia. One patient (3.6%) died of pneumonitis. For late toxicity, 2 patients (7.7%) had Grade 3 cough or dyspnea; none had severe dysphagia. Complete metabolic response was obtained in 44% (11 of 26 patients). With a median follow-up of 13 months, median overall survival was 19.6 months, with a 1-year survival rate of 57.1%. CONCLUSIONS Individualized maximal tolerable dose irradiation based on normal tissue dose constraints is feasible, and initial results are promising.
Radiotherapy and Oncology | 2009
Dirk De Ruysscher; Ans W. Houben; Hugo J.W.L. Aerts; C Dehing; Rinus Wanders; Michel Öllers; Anne-Marie C. Dingemans; Monique Hochstenbag; Liesbeth Boersma; Jacques Borger; Andre Dekker; Philippe Lambin
PURPOSE As Radiation-Induced Lung Toxicity (RILT) is dose-limiting for radiotherapy (RT) of lung cancer and current parameters are only moderately associated with RILT, we sought for novel parameters associated with RILT. PATIENTS AND METHODS In this prospective study, FDG-PET-CT scans were taken on days 0, 7 and 14 after initiation of high-dose RT in 18 patients with stage III non-small cell lung cancer. The maximal Standardized Uptake Value (SUV(max)) in the lung outside of the GTV was used as a measure of FDG uptake. At the same time-points, the serum IL-6 concentrations were measured. RILT was defined as dyspnea score 2 (CTCAE3.0). RESULTS Six of 18 patients developed RILT. Before RT, SUV(max) in the lung was not significantly different between patients who developed RILT and those who did not develop RILT. Patients who developed RILT post-radiation had a significant increased SUV on days 7 and 14 during RT, whereas the group that did not experience RILT showed no significant SUV changes. The SUV(max) of the lungs increased significantly more in the group that later developed RILT compared to those who did not develop RILT. Neither the IL-6 concentration nor the mean lung dose was associated with RILT. CONCLUSIONS The increase in FDG uptake in the normal lung early during RT was highly associated with the subsequent development of clinical RILT. This may help to identify patients at high risk for RILT at a time when adjustments of the treatment or strategies to prevent RILT are still possible.
Radiation Research | 2004
Jacqueline J. C M. Kruse; Johannes A. M. te Poele; Arno Velds; Ron M. Kerkhoven; Liesbeth Boersma; Nicola S. Russell; Fiona A. Stewart
Abstract Kruse, J. J. C. M., te Poele, J. A. M., Velds, A., Kerkhoven, R. M., Boersma, L. J., Russell, N. S. and Stewart, F. A. Identification of Differentially Expressed Genes in Mouse Kidney after Irradiation using Microarray Analysis. Radiat. Res. 161, 28–38 (2004). Irradiation of the kidney induces dose-dependent, progressive renal functional impairment, which is partly mediated by vascular damage. The molecular mechanisms underlying the development of radiation-induced nephropathy are unclear. Given the complexity of radiation-induced responses, microarrays may offer new opportunities to identify a wider range of genes involved in the development of radiation injury. The aim of the present study was to determine whether microarrays are a useful tool for identifying time-related changes in gene expression and potential mechanisms of radiation-induced nephropathy. Microarray experiments were performed using amplified RNA from irradiated mouse kidneys (1 × 16 Gy) and from sham-irradiated control tissue at different intervals (1–30 weeks) after irradiation. After normalization procedures (using information from straight-color, color-reverse and self-self experiments), the differentially expressed genes were identified. Control and repeat experiments were done to confirm that the observations were not artifacts of the array procedure (RNA amplification, probe synthesis, hybridizations and data analysis). To provide independent confirmation of microarray data, semi-quantitative PCR was performed on a selection of genes. At 1 week after irradiation (before the onset of vascular and functional damage), 16 genes were significantly up-regulated and 9 genes were down-regulated. During the period of developing nephropathy (10 to 20 weeks), 31 and 42 genes were up-regulated and 9 and 4 genes were down-regulated. At the later time of 30 weeks, the vast majority of differentially expressed genes (191 out of 203) were down-regulated. Potential genes of interest included TSA-1 (also known as Ly6e) and Jagged 1 (Jag1). Increased expression of TSA-1, a member of the Ly-6 family, has previously been reported in response to proteinuria. Jagged 1, a ligand for the Notch receptor, is known to play a role in angiogenesis, and is particularly interesting in the context of radiation-induced vascular injury. The present study demonstrates the potential of microarrays to identify changing patterns of gene expression in irradiated kidney. Further studies will be required to evaluate functional involvement of these genes in vascular-mediated normal tissue injury.